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Avigdor T, Minert A, Baron M, Devor M. Paradoxical anesthesia: Sleep-like EEG during anesthesia induced by mesopontine microinjection of GABAergic agents. Exp Neurol 2021; 343:113760. [PMID: 34000248 DOI: 10.1016/j.expneurol.2021.113760] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 04/08/2021] [Accepted: 05/10/2021] [Indexed: 12/20/2022]
Abstract
General anesthetic agents are thought to induce loss-of-consciousness (LOC) and enable pain-free surgery by acting on the endogenous brain circuitry responsible for sleep-wake cycling. In clinical use, the entire CNS is exposed to anesthetic molecules with LOC and amnesia usually attributed to synaptic suppression in the cerebral cortex and immobility and analgesia to agent action in the spinal cord and brainstem. This model of patch-wise suppression has been challenged, however, by the observation that all functional components of anesthesia can be induced by focal delivery of minute quantities of GABAergic agonists to the brainstem mesopontine tegmental anesthesia area (MPTA). We compared spectral features of the cortical electroencephalogram (EEG) in rats during systemic anesthesia and anesthesia induced by MPTA microinjection. Systemic administration of (GABAergic) pentobarbital yielded the sustained, δ-band dominant EEG signature familiar in clinical anesthesia. In contrast, anesthesia induced by MPTA microinjection (pentobarbital or muscimol) featured epochs of δ-band EEG alternating with the wake-like EEG, the pattern typical of natural non-rapid-eye-movement (NREM) and REM sleep. The rats were not sleeping, however, as they remained immobile, atonic and unresponsive to noxious pinch. Recalling the paradoxical wake-like quality the EEG during REM sleep, we refer to this state as "paradoxical anesthesia". GABAergic anesthetics appear to co-opt both cortical and spinal components of the sleep network via dedicated axonal pathways driven by MPTA neurons. Direct drug exposure of cortical and spinal neurons is not necessary, and is probably responsible for off-target side-effects of systemic administration including monotonous δ-band EEG, hypothermia and respiratory depression. SIGNIFICANCE STATEMENT: The concept that GABAergic general anesthetic agents induce loss-of-consciousness by substituting for an endogenous neurotransmitter, thereby co-opting neural circuitry responsible for sleep-wake transitions, has gained considerable traction. However, the electroencephalographic (EEG) signatures of sleep and anesthesia differ fundamentally. We show that when the anesthetic state is generated by focal delivery of GABAergics into the mesopontine tegmental anesthesia area (MPTA) the resulting EEG repeatedly transitions between delta-wave-dominant and wake-like patterns much as in REM-NREM sleep. This suggests that systemic (clinical) anesthetic delivery, which indiscriminately floods the entire cerebrum with powerful inhibitory agents, obscures the sleep-like EEG signature associated with the less adulterated form of anesthesia obtained when the drugs are applied selectively to loci where the effective neurotransmitter substitution actually occurs.
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Affiliation(s)
- Tamir Avigdor
- Department of Cell and Developmental Biology, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Anne Minert
- Department of Cell and Developmental Biology, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Mark Baron
- Department of Cell and Developmental Biology, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Marshall Devor
- Department of Cell and Developmental Biology, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel; Center for Research on Pain, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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Tripathi SJ, Chakraborty S, Rao BSS. Remediation of chronic immobilization stress-induced negative affective behaviors and altered metabolism of monoamines in the prefrontal cortex by inactivation of basolateral amygdala. Neurochem Int 2020; 141:104858. [PMID: 33010391 DOI: 10.1016/j.neuint.2020.104858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/06/2020] [Accepted: 09/26/2020] [Indexed: 01/28/2023]
Abstract
Exposure to chronic stress precipitates depression and anxiety. Stress-induced responses are differentially regulated by the prefrontal cortex (PFC) and basolateral amygdala (BLA). For instance, repeated stress leads to hypertrophy of BLA, resulting in the emergence of affective symptoms. Chronic stress-induced changes in the metabolism of monoamines are central in the manifestation of affective symptoms. Interestingly, BLA via its reciprocal connections modulates prefrontal cortical monoaminergic responses to acute stress. However, the effects of BLA inactivation on chronic stress-induced affective behaviors and monoaminergic changes in the PFC are relatively unknown. Thus, we hypothesized that inactivation of BLA might prevent chronic immobilization stress (CIS)-induced depressive-, anxiety-like behaviors, and associated monoaminergic alterations in the prelimbic (PrL) and anterior cingulate cortex (ACC) subregions of PFC. We used two different BLA silencing strategies, namely ibotenic acid lesion and reversible temporary inactivation using lidocaine. We found that CIS precipitates depressive- and anxiety-like behaviors. Further, CIS-induced negative affective behaviors were associated with decreased levels of 5-HT, DA, and NE, and increased 5-HIAA/5-HT, DOPAC + HVA/DA, and MHPG/NE ratio in the PrL and ACC, suggesting enhanced metabolism. Interestingly, BLA lesion prior to CIS blocked the emergence of depressive- and anxiety-like behaviors. Moreover, the lesion of BLA prior to CIS was sufficient to prevent alterations in levels of monoamines and their metabolites in the PrL and ACC. Thereafter, we evaluated whether the effects of BLA lesion could be mirrored by temporary inactivation of BLA, specifically during stress. Remarkably, temporary inactivation of BLA during stress recapitulated the effects of lesion. Our results have implications for understanding the role of BLA in chronic stress-induced metabolic alterations in prefrontal cortical monoaminergic systems, and associated mood and anxiety disorders. The current study supports the hypothesis that combating amygdalar hyperactivity might be a viable strategy for the management of stress and associated affective disorders.
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Affiliation(s)
- Sunil Jamuna Tripathi
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru, 560 029, India
| | - Suwarna Chakraborty
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru, 560 029, India
| | - B S Shankaranarayana Rao
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru, 560 029, India.
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Brasil TFS, Lopes-Azevedo S, Belém-Filho IJA, Fortaleza EAT, Antunes-Rodrigues J, Corrêa FMA. The Dorsomedial Hypothalamus Is Involved in the Mediation of Autonomic and Neuroendocrine Responses to Restraint Stress. Front Pharmacol 2020; 10:1547. [PMID: 32038236 PMCID: PMC6989482 DOI: 10.3389/fphar.2019.01547] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/29/2019] [Indexed: 01/18/2023] Open
Abstract
We hypothesized that dorsomedial hypothalamus (DMH) modulates autonomic and neuroendocrine responses in rats at rest and when subjected to restraint stress (RS). Male Wistar rats were used, and guide cannulas were bilaterally implanted in the DMH for microinjection of vehicle or the nonspecific synaptic blocker CoCl2 (1 mM/100 nl). A polyethylene catheter was inserted into the femoral artery for the recording of arterial pressure and heart rate (HR). Tail temperature was measured using a thermal camera. The session of RS started 10 min after DMH treatment with vehicle or CoCl2. Under home-cage condition, the pretreatment of DMH with CoCl2 increased baseline blood pressure (BP), and heart rate (HR) without affecting the tail temperature. In addition, it decreased plasma vasopressin levels without affecting plasma corticosterone and oxytocin contents. When rats pretreated with CoCl2 were exposed to RS, the RS-evoked cardiovascular were similar to those observed in vehicle-treated animals; however, because cobalt pretreatment of the DMH increased baseline BP and HR values, and the RS-evoked cardiovascular responses did not exceed those observed in vehicle-treated animals, suggesting a possible celling limit, the possibility that DMH is involved in the modulation of RS-evoked cardiovascular responses cannot be certainly excluded. Nonetheless, the pretreatment of DMH with CoCl2 blocked the reduction in tail temperature caused by RS. The DMH pretreatment with CoCl2 did not modify the RS-evoked increase in plasma corticosterone and oxytocin contents. In conclusion, the present data suggest the involvement of DMH in the maintenance of BP, HR, and vasopressin release under the rest conditions at the home-cage. Furthermore, indicate that DMH is an important thermoregulatory center during exposure to RS, regulating tail artery vasoconstriction.
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Affiliation(s)
- Taíz F S Brasil
- Department of Pharmacology of the School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Silvana Lopes-Azevedo
- Department of Pharmacology of the School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Ivaldo J A Belém-Filho
- Department of Pharmacology of the School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Eduardo A T Fortaleza
- Department of Pharmacology of the School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - José Antunes-Rodrigues
- Department of Physiology of the School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Fernando M A Corrêa
- Department of Pharmacology of the School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
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Tripathi SJ, Chakraborty S, Srikumar BN, Raju TR, Shankaranarayana Rao BS. Basolateral amygdalar inactivation blocks chronic stress-induced lamina-specific reduction in prefrontal cortex volume and associated anxiety-like behavior. Prog Neuropsychopharmacol Biol Psychiatry 2019; 88:194-207. [PMID: 30036565 DOI: 10.1016/j.pnpbp.2018.07.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 07/12/2018] [Accepted: 07/15/2018] [Indexed: 12/20/2022]
Abstract
Chronic exposure to stress causes cognitive deficits, anxiety and depression. Earlier studies have suggested that the prefrontal cortex (PFC) and basolateral amygdala (BLA) can differentially modulate the stress-induced alterations either by their action on HPA axis or via direct reciprocal connections between them. The PFC dysfunction and BLA hypertrophy following stress are known to cause anxiety and affective symptoms. Recent studies indicate that inactivation of BLA projections to PFC remarkably decreases anxiety. However, the effect of BLA inactivation on stress-induced anxiety and associated volume loss in prelimbic (PrL) and anterior cingulate (ACC) subregions of PFC is not known. Accordingly, we evaluated the effect of BLA lesion or inactivation during chronic immobilization stress (CIS) on an approach-avoidance task and associated volume loss in the PFC. The stressed rats showed a significant volumetric reduction in layer I and II of the PrL and ACC. Interestingly, BLA lesion prior to stress prevented the volume loss in PrL and ACC. Further, BLA lesion blocked the anxiety-like behavior in stressed rats. However, in the absence of stress, BLA lesion increased the number of shocks as compared to controls. As BLA lesion produced an anticonflict effect, we performed temporary inactivation of BLA specifically during stress. Similar to BLA lesion, lidocaine-induced inactivation prevented the stress-induced volume loss and anxiety-like behavior. We demonstrate that inactivation of BLA during stress prevents CIS-induced anxiety and associated structural correlates in the PFC. The present study extends the hypothesis of amygdalar silencing as a possible management strategy for stress and associated disorders.
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Affiliation(s)
- Sunil Jamuna Tripathi
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru 560 029, India
| | - Suwarna Chakraborty
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru 560 029, India
| | - B N Srikumar
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru 560 029, India
| | - T R Raju
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru 560 029, India
| | - B S Shankaranarayana Rao
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru 560 029, India.
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Ji NN, Kang J, Hua R, Zhang YM. Involvement of dopamine system in the regulation of the brain corticotropin-releasing hormone in paraventricular nucleus in a rat model of chronic visceral pain. Neurol Res 2018; 40:650-657. [PMID: 29623778 DOI: 10.1080/01616412.2018.1460702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Objective We aimed to investigate the mechanism of paraventricular nucleus (PVN) and ventral tegmental area (VTA) circuit in the pathogenesis of visceral pain-depression with a rat model induced by neonatal and adult colorectal distension (CRD). Methods Neonate male Sprague-Dayley (SD) rats underwent CRD on postnatal days 8, 10, and 12, and when matured, were tested for adult abdominal withdrawal reflex (AWR) scores to assess visceral hypersensitivity. The forced swimming test was employed to evaluate depression-like behaviors. The rats exhibiting visceral pain-depressive behaviors underwent lidocaine injection in the VTA to explore the relationship between VTA and visceral pain. Moreover, double immunofluorescence was employed to evaluate the qualitative and quantitative expression of dopamine/ c-Fos in CRD rats. After verifying the existed fiber projection from PVN to VTA, the intra-PVN microinjection of CRH-RNAi lentivirus to inhibit corticotropin-releasing hormone (CRH) expression, behavioral changes were assessed by AWR score and FST. Thereafter, with the sacrifice of the rats, the variations of TH protein in rats were evaluated by immunofluorescence and Western blot. Results Intra-VTA microinjection of lidocaine increased the pain threshold of CRD group. After intra-VTA microinjection of green retrograde tracer, immunofluorescence photomicrographs visualized the PVN with a typical green retrograde tracer. Intra-PVN microinjection of CRH-RNAi lentivirus alleviated the visceral pain-depression behaviors and decreased the TH protein expression in the VTA. Conclusion These data demonstrated that the VTA played a functional role in chronic visceral pain and depression, and the CRH-containing neurons in hypothalamic PVN may be implicated in the onset and maintenance of the chronic visceral pain and depression via the activation of dopamine in the VTA.
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Affiliation(s)
- Ning-Ning Ji
- a Jiangsu Province Key Laboratory of Anesthesiology , Xuzhou Medical University , Xuzhou , China
| | - Jie Kang
- a Jiangsu Province Key Laboratory of Anesthesiology , Xuzhou Medical University , Xuzhou , China.,c Emergency Center of the Affiliated Hospital of Xuzhou Medical University , Xuzhou , China
| | - Rong Hua
- b Institute of Emergency Rescue Medicine , Xuzhou Medical University , Xuzhou , China.,c Emergency Center of the Affiliated Hospital of Xuzhou Medical University , Xuzhou , China
| | - Yong-Mei Zhang
- a Jiangsu Province Key Laboratory of Anesthesiology , Xuzhou Medical University , Xuzhou , China
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Bassi GS, Dias DPM, Franchin M, Talbot J, Reis DG, Menezes GB, Castania JA, Garcia-Cairasco N, Resstel LBM, Salgado HC, Cunha FQ, Cunha TM, Ulloa L, Kanashiro A. Modulation of experimental arthritis by vagal sensory and central brain stimulation. Brain Behav Immun 2017; 64:330-343. [PMID: 28392428 PMCID: PMC6330674 DOI: 10.1016/j.bbi.2017.04.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/25/2017] [Accepted: 04/04/2017] [Indexed: 12/20/2022] Open
Abstract
Articular inflammation is a major clinical burden in multiple inflammatory diseases, especially in rheumatoid arthritis. Biological anti-rheumatic drug therapies are expensive and increase the risk of systemic immunosuppression, infections, and malignancies. Here, we report that vagus nerve stimulation controls arthritic joint inflammation by inducing local regulation of innate immune response. Most of the previous studies of neuromodulation focused on vagal regulation of inflammation via the efferent peripheral pathway toward the viscera. Here, we report that vagal stimulation modulates arthritic joint inflammation through a novel "afferent" pathway mediated by the locus coeruleus (LC) of the central nervous system. Afferent vagal stimulation activates two sympatho-excitatory brain areas: the paraventricular hypothalamic nucleus (PVN) and the LC. The integrity of the LC, but not that of the PVN, is critical for vagal control of arthritic joint inflammation. Afferent vagal stimulation suppresses articular inflammation in the ipsilateral, but not in the contralateral knee to the hemispheric LC lesion. Central stimulation is followed by subsequent activation of joint sympathetic nerve terminals inducing articular norepinephrine release. Selective adrenergic beta-blockers prevent the effects of articular norepinephrine and thereby abrogate vagal control of arthritic joint inflammation. These results reveals a novel neuro-immune brain map with afferent vagal signals controlling side-specific articular inflammation through specific inflammatory-processing brain centers and joint sympathetic innervations.
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Affiliation(s)
- Gabriel Shimizu Bassi
- Department of Immunology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil.
| | | | - Marcelo Franchin
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Jhimmy Talbot
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Daniel Gustavo Reis
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Gustavo Batista Menezes
- Center for Gastrointestinal Biology, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Jaci Airton Castania
- Department of Physiology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Norberto Garcia-Cairasco
- Department of Physiology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Helio Cesar Salgado
- Department of Physiology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernando Queiró Cunha
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Thiago Mattar Cunha
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luis Ulloa
- Department of Surgery, Center of Immunology & Inflammation, Rutgers-New Jersey Medical School, Rutgers University, Newark, NJ 07101, USA.
| | - Alexandre Kanashiro
- Department of Pharmacology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Physiological Sciences, Federal University of São Carlos, São Carlos, SP, Brazil.
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Charntikov S, Pittenger ST, Swalve N, Li M, Bevins RA. Double dissociation of the anterior and posterior dorsomedial caudate-putamen in the acquisition and expression of associative learning with the nicotine stimulus. Neuropharmacology 2017; 121:111-119. [PMID: 28457971 PMCID: PMC5509027 DOI: 10.1016/j.neuropharm.2017.04.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 04/13/2017] [Accepted: 04/17/2017] [Indexed: 01/27/2023]
Abstract
Tobacco use is the leading cause of preventable deaths worldwide. This habit is not only debilitating to individual users but also to those around them (second-hand smoking). Nicotine is the main addictive component of tobacco products and is a moderate stimulant and a mild reinforcer. Importantly, besides its unconditional effects, nicotine also has conditioned stimulus effects that may contribute to the tenacity of the smoking habit. Because the neurobiological substrates underlying these processes are virtually unexplored, the present study investigated the functional involvement of the dorsomedial caudate putamen (dmCPu) in learning processes with nicotine as an interoceptive stimulus. Rats were trained using the discriminated goal-tracking task where nicotine injections (0.4 mg/kg; SC), on some days, were paired with intermittent (36 per session) sucrose deliveries; sucrose was not available on interspersed saline days. Pre-training excitotoxic or post-training transient lesions of anterior or posterior dmCPu were used to elucidate the role of these areas in acquisition or expression of associative learning with nicotine stimulus. Pre-training lesion of p-dmCPu inhibited acquisition while post-training lesions of p-dmCPu attenuated the expression of associative learning with the nicotine stimulus. On the other hand, post-training lesions of a-dmCPu evoked nicotine-like responding following saline treatment indicating the role of this area in disinhibition of learned motor behaviors. These results, for the first time, show functionally distinct involvement of a- and p-dmCPu in various stages of associative learning using nicotine stimulus and provide an initial account of neural plasticity underlying these learning processes.
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Affiliation(s)
- Sergios Charntikov
- Department of Psychology, University of New Hampshire, Durham, NH, United States.
| | - Steven T Pittenger
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Natashia Swalve
- Department of Psychology, Alma College, Alma, MI, United States
| | - Ming Li
- Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, United States
| | - Rick A Bevins
- Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, United States
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8
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Carreno FR, Collins GT, Frazer A, Lodge DJ. Selective Pharmacological Augmentation of Hippocampal Activity Produces a Sustained Antidepressant-Like Response without Abuse-Related or Psychotomimetic Effects. Int J Neuropsychopharmacol 2017; 20:504-509. [PMID: 28339593 PMCID: PMC5458335 DOI: 10.1093/ijnp/pyx003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 01/13/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Selective augmentation of hippocampal activity in ways similar to that caused by ketamine may have therapeutic advantages over ketamine, which has psychotomimetic and reinforcing effects likely due to effects outside the hippocampus (i.e., off-target effects). METHODS Here we evaluated the antidepressant-like response to a negative allosteric modulator of α5 subunit- containing gamma aminobutyric acid subtype A receptors, L-655,708, as these receptors are expressed to a much greater extent in the hippocampus than in other brain areas. RESULTS Systemic administration of L-655,708 produced a sustained antidepressant-like effect in the forced swim test that was comparable with that of ketamine and was blocked by hippocampal inactivation with lidocaine. However, in contrast to ketamine, L-655,708 did not affect prepulse inhibition of startle, nor did it maintain responding in rats trained to self-administer i.v. ketamine. CONCLUSION Taken together, these findings suggest that activation of the hippocampus by L-655,708 produces an antidepressant-like effect in the absence of any psychotomimetic or abuse-related effects.
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Affiliation(s)
- Flavia R. Carreno
- Department of Pharmacology (Drs Carreno, Collins, Frazer, and Lodge), and Center for Biomedical Neuroscience (Drs Carreno, Frazer, and Lodge), University of Texas Health Science Center, San Antonio, Texas; South Texas Veterans Health Care System, San Antonio, Texas (Drs Collins and Frazer)
| | - Gregory T. Collins
- Department of Pharmacology (Drs Carreno, Collins, Frazer, and Lodge), and Center for Biomedical Neuroscience (Drs Carreno, Frazer, and Lodge), University of Texas Health Science Center, San Antonio, Texas; South Texas Veterans Health Care System, San Antonio, Texas (Drs Collins and Frazer)
| | - Alan Frazer
- Department of Pharmacology (Drs Carreno, Collins, Frazer, and Lodge), and Center for Biomedical Neuroscience (Drs Carreno, Frazer, and Lodge), University of Texas Health Science Center, San Antonio, Texas; South Texas Veterans Health Care System, San Antonio, Texas (Drs Collins and Frazer)
| | - Daniel J. Lodge
- Department of Pharmacology (Drs Carreno, Collins, Frazer, and Lodge), and Center for Biomedical Neuroscience (Drs Carreno, Frazer, and Lodge), University of Texas Health Science Center, San Antonio, Texas; South Texas Veterans Health Care System, San Antonio, Texas (Drs Collins and Frazer)
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9
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Göktalay G, Millington WR. Hypovolemic hemorrhage induces Fos expression in the rat hypothalamus: Evidence for involvement of the lateral hypothalamus in the decompensatory phase of hemorrhage. Neuroscience 2016; 322:464-78. [PMID: 26947128 DOI: 10.1016/j.neuroscience.2016.02.068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 02/10/2016] [Accepted: 02/27/2016] [Indexed: 01/02/2023]
Abstract
This study tested the hypothesis that the hypothalamus participates in the decompensatory phase of hemorrhage by measuring Fos immunoreactivity and by inhibiting neuronal activity in selected hypothalamic nuclei with lidocaine or cobalt chloride. Previously, we reported that inactivation of the arcuate nucleus inhibited, but did not fully prevent, the fall in arterial pressure evoked by hypotensive hemorrhage. Here, we report that hemorrhage (2.2 ml/100g body weight over 20 min) induced Fos expression in a high percentage of cells in the paraventricular, supraoptic and arcuate nuclei of the hypothalamus as shown previously. Lower densities of Fos immunoreactive cells were also found in the medial preoptic area (mPOA), anterior hypothalamus, lateral hypothalamus (LH), dorsomedial hypothalamus, ventromedial hypothalamus (VMH) and posterior hypothalamus. Bilateral injection of lidocaine (2%; 0.1 μl or 0.3 μl) or cobalt chloride (5mM; 0.3 μl) into the tuberal portion of the LH immediately before hemorrhage was initiated reduced the magnitude of hemorrhagic hypotension and bradycardia significantly. Lidocaine injection into the VMH also attenuated the fall in arterial pressure and heart rate evoked by hemorrhage although inactivation of the mPOA or rostral LH was ineffective. These findings indicate that hemorrhage activates neurons throughout much of the hypothalamus and that a relatively broad area of the hypothalamus, extending from the arcuate nucleus laterally through the caudal VMH and tuberal LH, plays an important role in the decompensatory phase of hemorrhage.
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Affiliation(s)
- G Göktalay
- Department of Medical Pharmacology, Uludag University, Faculty of Medicine, Bursa, Turkey
| | - W R Millington
- Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, Albany, NY, United States.
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Jäger K, Kössl M. Corticofugal Modulation of DPOAEs in Gerbils. Hear Res 2015; 332:61-72. [PMID: 26619750 DOI: 10.1016/j.heares.2015.11.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 10/20/2015] [Accepted: 11/09/2015] [Indexed: 01/13/2023]
Abstract
Efferent auditory feedback on cochlear hair cells is well studied regarding olivocochlear brainstem mechanisms. Less is known about how the descending corticofugal system may shape efferent feedback and modulate cochlear mechanics. Distortion-product otoacoustic emissions (DPOAEs) are a suitable tool to assess outer hair cell function, as they are by-products of the nonlinear cochlear amplification process. The present project investigates the effects of cortical activity on cubic and quadratic DPOAEs in mongolian gerbils, Meriones unguiculatus, through cortical deactivation using the sodium-channel blocker lidocaine. Contralateral cortical microinjections of lidocaine can lead to either an increase or decrease of median DPOAE levels of up to 10.95 dB. The effects are reversible and comparable at all tested frequencies (0.5-40 kHz). They are not restricted to the preferred frequency of the cortical site of injection. Recovery times are between 20 and 120 min depending on stimulation levels and emission type. When the injection is performed in the ipsilateral hemisphere, DPOAE level shifts are lower in amplitude compared to those after injection in the contralateral hemisphere. No significant changes in DPOAE levels are obtained after saline microinjections. Results indicate that deactivation of auditory cortex activity through lidocaine has a considerable impact on peripheral auditory responses in form of DPOAEs, probably through cortico-olivocochlear pathways.
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Affiliation(s)
- K Jäger
- Institute for Cell Biology and Neuroscience, Goethe University Frankfurt, Max-von-Laue Str. 13, 60438 Frankfurt, Germany.
| | - M Kössl
- Institute for Cell Biology and Neuroscience, Goethe University Frankfurt, Max-von-Laue Str. 13, 60438 Frankfurt, Germany.
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11
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Feleder C, Sertac Yilmaz M, Peng J, Göktalay G, Millington WR. The OVLT initiates the fall in arterial pressure evoked by high dose lipopolysaccharide: evidence that dichotomous, dose-related mechanisms mediate endotoxic hypotension. J Neuroimmunol 2015. [PMID: 26198924 DOI: 10.1016/j.jneuroim.2015.05.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This study tested the hypothesis that lipopolysaccharide (LPS) lowers arterial pressure through two different mechanisms depending on the dose. Previously, we found that a low hypotensive dose of LPS (1mg/kg) lowers arterial pressure by activating vagus nerve afferents. Here we report that hypotension evoked by high dose LPS (15mg/kg) can be prevented by injecting lidocaine into the OVLT but not by vagotomy or inactivation of the NTS. The hypotension produced by both LPS doses was correlated with elevated extracellular norepinephrine concentrations in the POA and prevented by blocking alpha-adrenergic receptors. Thus, initiation of endotoxic hypotension is dose-related, mechanistically.
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Affiliation(s)
- Carlos Feleder
- Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, United States
| | - M Sertac Yilmaz
- Department of Medical Pharmacology, Uludag University, Faculty of Medicine, Bursa 16059, Turkey
| | - Jianya Peng
- Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, United States
| | - Gökhan Göktalay
- Department of Medical Pharmacology, Uludag University, Faculty of Medicine, Bursa 16059, Turkey
| | - William R Millington
- Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, United States.
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Almada RC, Coimbra NC. Recruitment of striatonigral disinhibitory and nigrotectal inhibitory GABAergic pathways during the organization of defensive behavior by mice in a dangerous environment with the venomous snakeBothrops alternatus(Reptilia,Viperidae). Synapse 2015; 69:299-313. [DOI: 10.1002/syn.21814] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 02/02/2015] [Accepted: 02/24/2015] [Indexed: 12/22/2022]
Affiliation(s)
- Rafael Carvalho Almada
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology; Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP); Ribeirão Preto São Paulo 14049-900 Brazil
- Institute of Neuroscience and Behaviour (INeC); Monte Alegre, Ribeirão Preto São Paulo 14050-220 Brazil
| | - Norberto Cysne Coimbra
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology; Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP); Ribeirão Preto São Paulo 14049-900 Brazil
- Institute of Neuroscience and Behaviour (INeC); Monte Alegre, Ribeirão Preto São Paulo 14050-220 Brazil
- NAP-USP-Neurobiology of Emotions Research Centre (NuPNE); Ribeirão Preto Medical School of the University of São Paulo; Ribeirão Preto São Paulo 14049-900 Brazil
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Yang FC, Liang K. Interactions of the dorsal hippocampus, medial prefrontal cortex and nucleus accumbens in formation of fear memory: Difference in inhibitory avoidance learning and contextual fear conditioning. Neurobiol Learn Mem 2014; 112:186-94. [DOI: 10.1016/j.nlm.2013.07.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 07/10/2013] [Accepted: 07/17/2013] [Indexed: 11/15/2022]
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Alves FHF, Crestani CC, Resstel LBM, Corrêa FMA. Both α1- and α2-adrenoceptors in the insular cortex are involved in the cardiovascular responses to acute restraint stress in rats. PLoS One 2014; 9:e83900. [PMID: 24404141 PMCID: PMC3880272 DOI: 10.1371/journal.pone.0083900] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 11/08/2013] [Indexed: 11/18/2022] Open
Abstract
The insular cortex (IC) is a limbic structure involved in cardiovascular responses observed during aversive threats. However, the specific neurotransmitter mediating IC control of cardiovascular adjustments to stress is yet unknown. Therefore, in the present study we investigated the role of local IC adrenoceptors in the cardiovascular responses elicited by acute restraint stress in rats. Bilateral microinjection of different doses (0.3, 5, 10 and 15 nmol/100 nl) of the selective α1-adrenoceptor antagonist WB4101 into the IC reduced both the arterial pressure and heart rate increases elicited by restraint stress. However, local IC treatment with different doses (0.3, 5, 10 and 15 nmol/100 nl) of the selective α2-adrenoceptor antagonist RX821002 reduced restraint-evoked tachycardia without affecting the pressor response. The present findings are the first direct evidence showing the involvement of IC adrenoceptors in cardiovascular adjustments observed during aversive threats. Our findings indicate that IC noradrenergic neurotransmission acting through activation of both α1- and α2-adrenoceptors has a facilitatory influence on pressor response to acute restraint stress. Moreover, IC α1-adrenoceptors also play a facilitatory role on restraint-evoked tachycardiac response.
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Affiliation(s)
- Fernando H. F. Alves
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
- * E-mail:
| | - Carlos C. Crestani
- Department of Natural Active Principles and Toxicology, School of Pharmaceutical Sciences of Araraquara, Univ. Estudual Paulista - UNESP, Araraquara, SP, Brazil
| | - Leonardo B. M. Resstel
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernando M. A. Corrêa
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
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Zhao XP, Yu L, Chen ZY, Hua R, Zhang YM. Effect of early-life stress on chronic functional visceral pain and CRH R1 expression in the paraventricular nucleus in adult rats. Shijie Huaren Xiaohua Zazhi 2013; 21:3344-3355. [DOI: 10.11569/wcjd.v21.i31.3344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To assess the effect of early-life stress on chronic functional visceral pain and expression of corticotropin releasing hormone receptor 1 (CRH R1) in the hypothalamic paraventricular nucleus (PVN) of rats with chronic functional visceral pain to provide a theoretical basis for the prevention and treatment of abdominal pain-related functional gastrointestinal disorders.
METHODS: Neonatal rats were randomly divided into six groups (n = 10), including a male control group, a female control group, a male separation group, a female separation group, a male distension group and a female distension group. HE staining was used to detect histologic changes in the colon tissue. Western blot and immunofluorescence were used to detect the changes in CRH R1 expression in the PVN. Brain tissue sections were immunostained for c-fos as a marker for activation of the PVN. Furthermore, normal male adult rats were randomly divided into three groups (normal control, saline and lidocaine, n = 6 for each group) to observe the role of PVN in the regulation of chronic functional visceral pain in normal rats by intra-PVN administration of lidocaine (1%, 0.3 µL).
RESULTS: Neonatal maternal separation (NMS) or colorectal distension (CRD) resulted in chronic visceral hypersensitivity without pathological changes in the colon tissue. There was no gender difference in the above change. Electrical discharge of the abdominal external oblique muscle in rats 10, 20, and 30 min after intra-PVN microinjection of 1% lidocaine was decreased significantly under the stimulation of CRD at 60 mmHg compared with normal controls and saline rats. The expression of CRH R1 and c-fos in the PVN of NMS and CRD rats increased compared with control rats.
CONCLUSION: Early-life stress can lead to chronic functional visceral pain in rats in adulthood. Allodynia caused by NMS is more obvious than that by CRD. The PVN and CRH R1 may be involved in the pathogenesis of chronic functional visceral pain caused by early-life stress.
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Xu B, Zheng H, Patel KP. Relative contributions of the thalamus and the paraventricular nucleus of the hypothalamus to the cardiac sympathetic afferent reflex. Am J Physiol Regul Integr Comp Physiol 2013; 305:R50-9. [PMID: 23616108 DOI: 10.1152/ajpregu.00004.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The cardiac sympathetic afferent reflex (CSAR) is induced by stimulating the cardiac sympathetic afferents, which evokes increases in sympathetic outflow and arterial pressure. In the present study, we attempted to identify the contribution of thalamic and hypothalamic nuclei involved in the CSAR. First, we observed that there was an increase in the number of c-Fos-labeled cells in the paraventricular nucleus (PVN) (190 ± 18 vs. 101 ± 15; P < 0.05), the paraventricular nucleus of the thalamus (PVT) (239 ± 23 vs. 151 ± 15; P < 0.05), and the mediodorsal thalamic nucleus (MD) (92 ± 9 vs. 63 ± 6; P < 0.05) following epicardial application of bradykinin (BK) compared with the control group (P < 0.05). Second, using extracellular single-unit recording, we found 25% of spontaneously active neurons in the thalamus were stimulated by epicardial application of BK or capsaicin in intact rats. However, 24% of spontaneously active neurons in the thalamus were still stimulated by epicardial application of BK or capsaicin despite vagotomy and sinoaortic denervation. None of the neurons in the thalamus responded to baroreflex changes in arterial pressure, induced by intravenous injection of phenylephrine or sodium nitroprusside. The CSAR was inhibited by microinjection of muscimol or lidocaine into the PVN. However, it was not inhibited or blocked by microinjection of muscimol or lidocaine into the thalamus. Taken together, these data suggest that the thalamus, while activated, is not critical for autonomic adjustments in response to activation of the CSAR. On the other hand, the PVN is critically involved in the central pathway of the CSAR.
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Affiliation(s)
- Bo Xu
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198-5850, USA
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Enhanced Adipose Afferent Reflex Contributes to Sympathetic Activation in Diet-Induced Obesity Hypertension. Hypertension 2012; 60:1280-6. [DOI: 10.1161/hypertensionaha.112.198002] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Effects of noradrenergic alpha-2 receptor antagonism or noradrenergic lesions in the ventral bed nucleus of the stria terminalis and medial preoptic area on maternal care in female rats. Psychopharmacology (Berl) 2012; 224:263-76. [PMID: 22644129 PMCID: PMC3652389 DOI: 10.1007/s00213-012-2749-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 05/12/2012] [Indexed: 12/22/2022]
Abstract
RATIONALE Maternal behavior in laboratory rats requires a network of brain structures including the ventral bed nucleus of the stria terminalis (BSTv) and medial preoptic area (mPOA). Neurotransmitter systems in the BSTv and mPOA influencing maternal behaviors are not well understood, although norepinephrine is an excellent candidate because the BSTv contains the densest noradrenergic fiber plexus in the forebrain and norepinephrine in the mPOA is known to influence other female reproductive functions. OBJECTIVES We hypothesized that downregulated noradrenergic activity in the BSTv and mPOA is necessary for mothering. METHODS Postpartum mother-litter interactions were observed after BSTv infusion of yohimbine (an α2 autoreceptor antagonist that increases norepinephrine release), and after BSTv or mPOA infusion of the more selective α2 autoreceptor antagonist idazoxan. Lastly, noradrenergic input to the BSTv/mPOA was selectively lesioned in nulliparous rats with anti-DBH-saporin to determine if this would facilitate mothering. RESULTS BSTv yohimbine almost abolished retrieval of pups but did not significantly affect dams' ability to initiate contact, lick, or nurse them. BSTv idazoxan disrupted retrieval somewhat less than yohimbine, but significantly reduced nursing. mPOA idazoxan impaired retrieval more severely than that found after BSTv infusion. Anti-DBH-saporin almost eliminated noradrenergic terminals in the BSTv and reduced them by over 60% in the mPOA, but did not promote maternal responding. It also did not affect females' anxiety-related behavior. CONCLUSIONS Downregulated noradrenergic activity in the BSTv and mPOA is necessary for postpartum maternal behavior in rats, but eliminating this system alone is insufficient to promote maternal behaviors in nulliparous females.
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Scopinho AA, Fortaleza EAT, Corrêa FMA. The medial amygdaloid nucleus is involved in the cardiovascular pathway activated by noradrenaline into the lateral septal area of rats. Eur J Neurosci 2012; 36:3059-65. [DOI: 10.1111/j.1460-9568.2012.08230.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Zhang L, Xiong XQ, Fan ZD, Gan XB, Gao XY, Zhu GQ. Involvement of enhanced cardiac sympathetic afferent reflex in sympathetic activation in early stage of diabetes. J Appl Physiol (1985) 2012; 113:47-55. [DOI: 10.1152/japplphysiol.01228.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cardiac sympathetic afferent reflex (CSAR) is involved in sympathetic activation. The present study was designed to investigate the contribution of enhanced CSAR to sympathetic activation in the early stage of diabetes and the involvement of AT1 receptors in the paraventricular nucleus (PVN). Diabetes was induced by a single intravenous injection of streptozotocin in rats. Acute experiments were carried out under anesthesia after 3 wk. The CSAR was evaluated by the responses of renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) to epicardial application of capsaicin or bradykinin. Sympathetic activity and CSAR were enhanced in diabetic rats. Plasma norepinephrine and angiotensin II were increased, but the transient receptor potential vanilloid 1 (TRPV1) in the left ventricle wall was not significantly increased in diabetic rats. Pericardial injection of resiniferatoxin to desensitize cardiac afferents or PVN microinjection of lidocaine attenuated the CSAR and decreased the RSNA and MAP in diabetic rats. The AT1 receptor expression in the PVN increased in diabetic rats. Angiotensin II in the PVN caused greater increases in the RSNA and MAP and enhancement in the CSAR in diabetic rats, which were abolished by the losartan pretreatment. Losartan decreased the RSNA and MAP and attenuated the CSAR in diabetic rats but not in control rats. These results indicate that the CSAR is enhanced in the early stage of diabetic rats, which contributes to the sympathetic activation. AT1 receptors in the PVN are involved in the enhanced CSAR in diabetic rats.
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Affiliation(s)
- Lei Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Xiao-Qing Xiong
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Zhi-Dan Fan
- Department of Rheumatology and Immunology, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, China
| | - Xian-Bing Gan
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Xing-Ya Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Guo-Qing Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
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Ghaderi A, Sarihi A, Komaki A, Shahidi S. Tetrodotoxin functional ablation of dorsal raphe before training impaired acquisition and retrieval of spatial reference memory in male rats. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.sbspro.2012.01.061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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22
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Involvement of the paraventricular nucleus (PVN) of hypothalamus in the cardiovascular alterations to head up tilt in conscious rats. Neurosci Res 2011; 72:270-4. [PMID: 22182743 DOI: 10.1016/j.neures.2011.12.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 09/25/2011] [Accepted: 12/02/2011] [Indexed: 11/21/2022]
Abstract
We evaluated the involvement of paraventricular nucleus (PVN) in the changes in mean arterial pressure (MAP) and heart rate (HR) during an orthostatic challenge (head up tilt, HUT). Adult male Wistar rats, instrumented with guide cannulas to PVN and artery and vein catheters were submitted to MAP and HR recording in conscious state and induction of HUT. The HUT induced an increase in MAP and HR and the pretreatment with prazosin and atenolol blocked these effects. After inhibition of neurotransmission with cobalt chloride (1 mM/100 nl) into the PVN the HR parameters did not change, however we observed a decrease in MAP during HUT. Our data suggest the involvement of PVN in the brain circuitry involved in cardiovascular adjustment during orthostatic challenges.
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Loureiro M, Lecourtier L, Engeln M, Lopez J, Cosquer B, Geiger K, Kelche C, Cassel JC, Pereira de Vasconcelos A. The ventral hippocampus is necessary for expressing a spatial memory. Brain Struct Funct 2011; 217:93-106. [PMID: 21667304 DOI: 10.1007/s00429-011-0332-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 05/21/2011] [Indexed: 10/18/2022]
Abstract
Current views posit the dorsal hippocampus (DHipp) as contributing to spatial memory processes. Conversely, the ventral hippocampus (VHipp) modulates stress, emotions and affects. Arguments supporting this segregation include differences in (i) connectivity: the DHipp is connected with the entorhinal cortex which receives visuospatial neocortical inputs; the VHipp is connected with both the amygdala and hypothalamus, (ii) electrophysiological characteristics: there is a larger proportion of place cells in the DHipp than in the VHipp, and an increasing dorsoventral gradient in the size of place fields, suggesting less refined spatial coding in the VHipp, and (iii) consequences of lesions: spatial memory is altered after DHipp lesions, less dramatically, sometimes not, after VHipp lesions. Using reversible inactivation, we report in rats, that lidocaine infusions into the DHipp or VHipp right before a probe trial impair retrieval performance in a water-maze task. This impairment was found at two post-acquisition delays compatible with recent memory (1 and 5 days). Pre-training blockade of the VHipp did not prevent task acquisition and drug-free retrieval, on the contrary to pre-training blockade of DHipp, which altered performance in a subsequent drug-free probe trial. Complementary experiments excluded possible locomotor, sensorimotor, motivational or anxiety-related biases from data interpretation. Our conclusion is that a spatial memory can be acquired with the DHipp, less efficiently with the VHipp, and that the retrieval of such a memory and/or the expression of its representation engages the dorsoventral axis of the hippocampus when the task has been learnt with an entirely functional hippocampus.
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Affiliation(s)
- Michael Loureiro
- Laboratoire d'Imagerie et de Neurosciences Cognitives, UMR 7237, Université de Strasbourg, CNRS, IFR 37 des Neurosciences, GDR CNRS 2905 Neuromem, 12 rue Goethe, 67000 Strasbourg, France
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du Hoffmann J, Kim JJ, Nicola SM. An inexpensive drivable cannulated microelectrode array for simultaneous unit recording and drug infusion in the same brain nucleus of behaving rats. J Neurophysiol 2011; 106:1054-64. [PMID: 21613588 DOI: 10.1152/jn.00349.2011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neurons are functionally segregated into discrete populations that perform specific computations. These computations, mediated by neuron-neuron electrochemical signaling, form the neural basis of behavior. Thus fundamental to a brain-based understanding of behavior is the precise determination of the contribution made by specific neurotransmitters to behaviorally relevant neural activity. To facilitate this understanding, we have developed a cannulated microelectrode array for use in behaving rats that enables simultaneous neural ensemble recordings and local infusion of drugs in the same brain nucleus. The system is inexpensive, easy to use, and produces robust and quantitatively reproducible drug effects on recorded neurons.
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Affiliation(s)
- Johann du Hoffmann
- Department of Psychiatry and Behavioral Science, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Norris SA, Hathaway EN, Taylor JA, Thach WT. Cerebellar inactivation impairs memory of learned prism gaze-reach calibrations. J Neurophysiol 2011; 105:2248-59. [PMID: 21389311 DOI: 10.1152/jn.01009.2010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Three monkeys performed a visually guided reach-touch task with and without laterally displacing prisms. The prisms offset the normally aligned gaze/reach and subsequent touch. Naive monkeys showed adaptation, such that on repeated prism trials the gaze-reach angle widened and touches hit nearer the target. On the first subsequent no-prism trial the monkeys exhibited an aftereffect, such that the widened gaze-reach angle persisted and touches missed the target in the direction opposite that of initial prism-induced error. After 20-30 days of training, monkeys showed long-term learning and storage of the prism gaze-reach calibration: they switched between prism and no-prism and touched the target on the first trials without adaptation or aftereffect. Injections of lidocaine into posterolateral cerebellar cortex or muscimol or lidocaine into dentate nucleus temporarily inactivated these structures. Immediately after injections into cortex or dentate, reaches were displaced in the direction of prism-displaced gaze, but no-prism reaches were relatively unimpaired. There was little or no adaptation on the day of injection. On days after injection, there was no adaptation and both prism and no-prism reaches were horizontally, and often vertically, displaced. A single permanent lesion (kainic acid) in the lateral dentate nucleus of one monkey immediately impaired only the learned prism gaze-reach calibration and in subsequent days disrupted both learning and performance. This effect persisted for the 18 days of observation, with little or no adaptation.
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Affiliation(s)
- Scott A Norris
- Department of Neurology, Washington University School of Medicine, Box 8111, 660 S. Euclid Ave., St. Louis, MO 63110, USA.
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Anzai M, Kitazawa H, Nagao S. Effects of reversible pharmacological shutdown of cerebellar flocculus on the memory of long-term horizontal vestibulo-ocular reflex adaptation in monkeys. Neurosci Res 2010; 68:191-8. [PMID: 20674618 DOI: 10.1016/j.neures.2010.07.2038] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 07/05/2010] [Accepted: 07/18/2010] [Indexed: 11/26/2022]
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Paraventricular nucleus modulates autonomic and neuroendocrine responses to acute restraint stress in rats. Auton Neurosci 2010; 158:51-7. [PMID: 20594922 DOI: 10.1016/j.autneu.2010.06.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 05/08/2010] [Accepted: 06/06/2010] [Indexed: 11/20/2022]
Abstract
The paraventricular nucleus of the hypothalamus (PVN) has been implicated in several aspects of neuroendocrine and cardiovascular control. The PVN contains parvocellular neurons that release the corticotrophin release hormone (CRH) under stress situations. In addition, this brain area is connected to several limbic structures implicated in defensive behavioral control, as well to forebrain and brainstem structures involved in cardiovascular control. Acute restraint is an unavoidable stress situation that evokes corticosterone release as well as marked autonomic changes, the latter characterized by elevated mean arterial pressure (MAP), intense heart rate (HR) increases and decrease in the tail temperature. We report the effect of PVN inhibition on MAP and HR responses, corticosterone plasma levels and tail temperature response during acute restraint in rats. Bilateral microinjection of the nonspecific synaptic blocker CoCl(2) (1 mM/100 nL) into the PVN reduced the pressor response; it inhibited the increase in plasma corticosterone concentration as well as the fall in tail temperature associated with acute restraint stress. Moreover, bilateral microinjection of CoCl(2) into areas surrounding the PVN did not affect the blood pressure, hormonal and tail vasoconstriction responses to restraint stress. The present results show that a local PVN neurotransmission is involved in the neural pathway that controls autonomic and neuroendocrine responses, which are associated with the exposure to acute restraint stress.
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Pereira M, Morrell JI. The medial preoptic area is necessary for motivated choice of pup- over cocaine-associated environments by early postpartum rats. Neuroscience 2010; 167:216-31. [PMID: 20156528 PMCID: PMC2850262 DOI: 10.1016/j.neuroscience.2010.02.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 02/04/2010] [Accepted: 02/09/2010] [Indexed: 11/23/2022]
Abstract
Converging evidence suggests that the motivation to seek cocaine during the postpartum period is significantly impacted by the competing incentives of offspring, a stimulus unique to this life stage. In the present study, the functional role of the medial preoptic area (mPOA), a critical site involved in maternal responsiveness, on processing incentive value of pup-associated cues and influencing response allocation for pup- over cocaine-associated environments was investigated using a concurrent pup/cocaine choice conditioned place preference (CPP) paradigm. Early postpartum females with bilateral guide cannulae aimed into the mPOA or into anatomical control sites were conditioned, from postpartum days (PPD) 4 to 7, to associate different uniquely featured environments with pups or cocaine. CPP was tested on PPD8 following intra-mPOA infusions of either 2% bupivacaine or saline vehicle. In two additional experiments, the effects of intra-mPOA infusions of bupivacaine on expression of conditioned responding induced by environments associated with either pups or cocaine were examined separately. Transient inactivation of the mPOA selectively blocked the conditioned preferences for pup-associated environments, significantly contrasting the robust pup-CPP found in non-surgical and intra-mPOA vehicle-treated females. In contrast, mPOA inactivation failed to alter cocaine-CPP in postpartum females. When given a choice between environments associated with pups or cocaine, transient functional inactivation of the mPOA altered choice behavior, biasing the preference of females toward cocaine-associated environments, such that almost all preferred cocaine- and none the pup-associated option. The anatomical specificity was revealed when inactivation of adjacent regions to the mPOA did not affect CPP responses for pups. The findings support a critical role for the mPOA in mediating pup-seeking behavior, and further suggest that the competing properties of pups over alternative incentives, including drugs of abuse, rely on mPOA integrity to provide relevant pup-related information to the circuitry underlying the choice behavior between pups and alternative stimuli.
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Affiliation(s)
- M Pereira
- Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, 197 University Avenue, Newark, NJ 07102-1814, USA.
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Saadé NE, Al Amin H, Tchachaghian S, Jabbur SJ, Atweh SF. Alteration of GABAergic and glycinergic mechanisms by lidocaine injection in the rostral ventromedial medulla of neuropathic rats. Pain 2010; 149:89-99. [DOI: 10.1016/j.pain.2010.01.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 01/15/2010] [Accepted: 01/15/2010] [Indexed: 11/28/2022]
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Pereira M, Morrell JI. The changing role of the medial preoptic area in the regulation of maternal behavior across the postpartum period: facilitation followed by inhibition. Behav Brain Res 2009; 205:238-48. [PMID: 19549547 PMCID: PMC2769204 DOI: 10.1016/j.bbr.2009.06.026] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Revised: 06/10/2009] [Accepted: 06/14/2009] [Indexed: 01/21/2023]
Abstract
Maternal behavior in rats undergoes considerable plasticity in parallel to the developmental stage of the pups, resulting in distinct patterns of maternal behavior and care at different postpartum time points. The medial preoptic area (mPOA) of the hypothalamus is one critical neural substrate underlying the onset and early expression of maternal behavior in rats but little is known about its specific functional role in the evolving expression of maternal behavior across the postpartum period. The present study uses a reversible local neural inactivation method to examine the role of the mPOA in the regulation of maternal behavior throughout the postpartum period, particularly extending into the late postpartum, a little examined period. This approach avoids the compensatory plasticity in CNS that occurs after permanent lesions, and allows the repeated testing of same individuals. Early (PPD7-8) and late (PPD13-14) postpartum maternal behavior was evaluated in female rats following infusions of bupivacaine or vehicle into the mPOA or into control areas. As expected, mPOA inactivation severely but transiently disrupted early postpartum maternal behavior whereas infusion of vehicle or inactivation of adjacent control sites did not. Later in the postpartum period, however, transient mPOA inactivation facilitated the expression of maternal behaviors, highly contrasting the behavioral expression levels characteristic of late postpartum. Results strongly demonstrate that the mPOA is differentially engaged throughout postpartum in orchestrating appropriate maternal responses with the developmental stage of the pups.
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Affiliation(s)
- Mariana Pereira
- Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, 197 University Avenue, Newark Campus, NJ 07102, USA.
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31
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Seip KM, Morrell JI. Transient inactivation of the ventral tegmental area selectively disrupts the expression of conditioned place preference for pup- but not cocaine-paired contexts. Behav Neurosci 2009; 123:1325-38. [PMID: 20001116 PMCID: PMC2828762 DOI: 10.1037/a0017666] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ventral tegmental area (VTA) plays a critical role in motivated behavior. However, it remains unclear whether intact VTA function is necessary for motivated behavior to seek contexts repeatedly paired with natural stimuli and/or pharmacological stimuli. In the present study, conditioned place preference (CPP) was induced with highly salient natural or drug stimuli attributed with strong incentive-motivational value in each of 2 female models: Postpartum females were conditioned to associate one unique context in the CPP apparatus with young offspring (pups) and a second context with a neutral stimulus, and virgin females were conditioned to associate unique contexts with cocaine (5 mg/kg ip) and saline injections. Immediately before CPP testing, each female received a microinfusion of bupivacaine bilaterally into the VTA to transiently inactivate the region; subjects were also tested after saline microinfusion into the VTA. Postpartum females' preference for the pup-paired context was abolished by VTA inactivation but was restored to high control levels after saline microinfusion. In separate tests, VTA inactivation also reduced motivated pup licking and pup retrieval in postpartum females, suggesting that intact VTA function is required for the expression of both pup CPP and motivated pup-directed behaviors. Cocaine CPP remained unaffected by VTA inactivation. Locomotion was not affected by VTA microinfusions but was severely impaired by bupivacaine microinfusions into the substantia nigra. We concluded that the VTA is differentially involved in the expression of conditioned preference for contexts paired with pups, a salient natural stimulus, and contexts paired with cocaine.
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Affiliation(s)
- Katharine M Seip
- Center for Molecular & Behavioral Neuroscience, Rutgers-The State University of New Jersey, Newark, NJ 07102, USA.
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32
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Abstract
The trigemino-cardiac reflex (TCR) is clinically defined as the sudden onset of parasympathetic activity, sympathetic hypotension, apnea, or gastric hypermotility during central or peripheral stimulation of any of the sensory branches of the trigeminal nerve. Clinically, the TCR has been reported to occur during craniofacial surgery, manipulation of the trigeminal nerve/ganglion and during surgery for lesion in the cerebellopontine angle, cavernous sinus, and the pituitary fossa. Apart from the few clinical reports, the physiologic function of this brainstem reflex has not yet been fully explored. The manifestation of the TCR can vary from bradycardia and hypotension to asystole. From the experimental findings, the TCR represents an expression of a central reflex leading to rapid cerebrovascular vasodilatation generated from excitation of oxygen-sensitive neurons in the rostral ventro-lateral medulla oblongata. By this physiologic response, the systemic and cerebral circulations may be adjusted in a way that augments cerebral perfusion. This review summarizes the current state of knowledge about TCR.
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Nucleus of solitary tract mediates cardiac sympathetic afferent reflex in rats. Pflugers Arch 2009; 459:1-9. [DOI: 10.1007/s00424-009-0699-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 06/27/2009] [Accepted: 07/03/2009] [Indexed: 02/07/2023]
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N-methyl-d-aspartate receptors in the insular cortex modulate baroreflex in unanesthetized rats. Auton Neurosci 2009; 147:56-63. [DOI: 10.1016/j.autneu.2008.12.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 12/04/2008] [Accepted: 12/23/2008] [Indexed: 01/15/2023]
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Tavares RF, Pelosi GG, Corrêa FMA. The paraventricular nucleus of the hypothalamus is involved in cardiovascular responses to acute restraint stress in rats. Stress 2009; 12:178-85. [PMID: 18609300 DOI: 10.1080/10253890802246659] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The paraventricular nucleus of the hypothalamus (PVN) has been implicated in several aspects of cardiovascular control. Stimulation of the PVN evokes changes in blood pressure and heart rate. Additionally, this brain area is connected to several limbic structures implicated in behavioral control, as well as to forebrain and brainstem structures involved in cardiovascular control. This evidence indicates that the PVN may modulate cardiovascular correlates of behavioral responses to stressful stimuli. Acute restraint is an unavoidable stressor that evokes marked and sustained cardiovascular changes, which are characterized by elevated mean arterial pressure (MAP) and an intense heart rate (HR) increase. We report on the effect of inhibition of PVN synapses on MAP and HR responses evoked by acute restraint in rats. Bilateral microinjection of the nonspecific synaptic blocker cobalt (CoCl(2), 1 mM/100 nl) into the PVN did not change the HR response or the initial peak of the MAP response to restraint stress, but reduced the area under the curve of the MAP response. Moreover, bilateral microinjection of cobalt in areas surrounding the PVN did not change the cardiovascular response to restraint. These results indicate that synapses in the PVN are involved in the neural pathway that controls blood pressure changes evoked by restraint.
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Affiliation(s)
- Rodrigo Fiacadori Tavares
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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36
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Brightwell JJ, Taylor BK. Noradrenergic neurons in the locus coeruleus contribute to neuropathic pain. Neuroscience 2009; 160:174-85. [PMID: 19223010 DOI: 10.1016/j.neuroscience.2009.02.023] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 01/20/2009] [Accepted: 02/04/2009] [Indexed: 12/17/2022]
Abstract
Current theories of neuropathic hypersensitivity include an imbalance of supraspinal inhibition and facilitation. Our overall hypothesis is that the locus coeruleus (LC), classically interpreted as a source of pain inhibition, may paradoxically result in facilitation after tibial and common peroneal nerve transection (spared sural nerve injury--SNI). We first tested the hypothesis that non-noxious tactile hind paw stimulation of the spared sural innervation territory increases neuronal activity in the LC in male rats. We observed a bilateral increase in the stimulus-evoked expression of transcription factors Fos and phosphorylated CREB (pCREB) in LC after SNI but not sham surgery; these markers of neuronal activity correlated with the intensity of tactile allodynia. We next tested the hypothesis that noradrenergic neurons contribute to the development of neuropathic pain. To selectively destroy these neurons, we delivered antidopamine-beta-hydroxylase saporin (anti-DbetaH-saporin) into the i.c.v. space 2 weeks before SNI. We found that anti-DbetaH-saporin, but not an IgG-saporin control, reduced behavioral signs of tactile allodynia, mechanical hyperalgesia, and cold allodynia from 3 to 28 days. after SNI. Our final experiment tested the hypothesis that the LC contributes to the maintenance of neuropathic pain. We performed SNI, waited 2 weeks for maximal allodynia and hyperalgesia to develop, and then administered the local anesthetic lidocaine (4%) directly into the LC parenchyma. Lidocaine reduced all behavioral signs of neuropathic pain in a reversible manner, suggesting that the LC contributes to pain facilitation. We conclude that, in addition to its well-known inhibition of acute and inflammatory pain, the LC facilitates the development and maintenance of neuropathic pain in the SNI model. Further studies are needed to determine the facilitatory pathways emanating from the LC.
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Affiliation(s)
- J J Brightwell
- Department of Pharmacology, School of Medicine, Tulane University, New Orleans, LA 70112, USA
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37
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The medial forebrain bundle mediates cardiovascular responses to electrical stimulation of the medial prefrontal cortex. Auton Neurosci 2009; 147:38-47. [PMID: 19185547 DOI: 10.1016/j.autneu.2009.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 12/30/2008] [Accepted: 01/05/2009] [Indexed: 02/05/2023]
Abstract
The medial prefrontal cortex (MPFC) is involved in cardiovascular control. MPFC electrical stimulation has been reported to cause depressor and bradycardic responses in anesthetized rats. Although the pathway involved is yet unknown, there is evidence indicating the existence of a relay in the lateral hypothalamus (LH). The medial forebrain bundle (MFB) that courses in the lateral portion of the LH carries the vast majority of telencephalic afferent as well efferent projections, including those from the MPFC. To evaluate if the hypotensive pathway originating in the MPFC courses the MFB, we studied the effect of coronal or sagittal knife cuts through the LH and other brain areas on the cardiovascular responses to MPFC electrical stimulation. Knife cuts were performed using blades 1 to 6 mm wide. Results indicate that the neural pathway descending from the MFB decussates early in the vicinity of MPFC, crossing the midline within the corpus callosum and yielding two descending pathways that travel rostro-caudally in the lateral portion of the LH, within the MFB. The decussation was confirmed by histological analysis of brain sections processed after the injection of biotinilated dextran amine in the site of the stimulation in the MPFC. Because knife cuts through the LH ipsilateral had minimal effects on the cardiovascular responses and knife cuts performed contralateral to the stimulated MPFC had no effect on the response to MPFC stimulation, data indicate that the contralateral limb of the pathway may be only activated as an alternative pathway when the ipsilateral pathway is blocked.
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Scopinho AA, Tavares RF, Busnardo C, Corrêa FMA. Non-N-methyl-D-aspartate glutamate receptors in the paraventricular nucleus of hypothalamus mediate the pressor response evoked by noradrenaline microinjected into the lateral septal area in rats. J Neurosci Res 2008; 86:3203-11. [DOI: 10.1002/jnr.21756] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Willuhn I, Steiner H. Skill-memory consolidation in the striatum: critical for late but not early long-term memory and stabilized by cocaine. Behav Brain Res 2008; 199:103-7. [PMID: 18687364 DOI: 10.1016/j.bbr.2008.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Revised: 07/09/2008] [Accepted: 07/10/2008] [Indexed: 10/21/2022]
Abstract
The sensorimotor striatum is important for procedural learning, including skill learning. Our previous findings indicate that this part of the striatum mediates the acquisition of a motor skill in a running-wheel task and that this skill learning is dependent on striatal D1 dopamine receptors. Here, we investigated whether the sensorimotor striatum is also involved in the consolidation of this skill memory and whether this consolidation is modified by the indirect dopamine receptor agonist cocaine. Rats were trained on a running wheel for 2 days (40 min/day) to learn a new motor skill, that is, the ability to control the movement of the wheel. Before each training session, the animals received an injection of vehicle or cocaine (25mg/kg, i.p.). Immediately following the training session, an intrastriatal infusion of 2% lidocaine (1 microl) or a sham infusion were administered. Wheel-skill performance was tested before and repeatedly after the training. Our results show that post-trial intrastriatal infusion of lidocaine disrupted late-stage long-term skill memory (post-training days 6-26), but spared early long-term memory (1 day after the training). Skill consolidation was more susceptible to such disruption in animals that practiced less during the training. Cocaine given pre-trial prevented this post-trial disruption of skill consolidation. These findings indicate that the sensorimotor striatum is critical for the consolidation of late but not early long-term skill memory. Furthermore, cocaine appeared to stabilize motor-memory formation by protecting consolidation processes after the training.
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Affiliation(s)
- Ingo Willuhn
- Department of Cellular and Molecular Pharmacology, Rosalind Franklin University of Medicine and Science/The Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064, USA
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40
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Inactivation of the anterior cingulate cortex blocks expression of remote, but not recent, conditioned taste aversion memory. Learn Mem 2008; 15:290-3. [DOI: 10.1101/lm.905008] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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41
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Walton MMG, Bechara B, Gandhi NJ. Effect of reversible inactivation of superior colliculus on head movements. J Neurophysiol 2008; 99:2479-95. [PMID: 18305088 DOI: 10.1152/jn.01112.2007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Because of limitations in the oculomotor range, many gaze shifts must be accomplished using coordinated movements of the eyes and head. Stimulation and recording data have implicated the primate superior colliculus (SC) in the control of these gaze shifts. The precise role of this structure in head movement control, however, is not known. The present study uses reversible inactivation to gain insight into the role of this structure in the control of head movements, including those that accompany gaze shifts and those that occur in the absence of a change in gaze. Forty-five lidocaine injections were made in two monkeys that had been trained on a series of behavioral tasks that dissociate movements of the eyes and head. Reversible inactivation resulted in clear impairments in the animals' ability to perform gaze shifts, manifested by increased reaction times, lower peak velocities, and increased durations. In contrast, comparable effects were not found for head movements (with or without gaze shifts) with the exception of a very small increase in reaction times of head movements associated with gaze shifts. Eye-head coordination was clearly affected by the injections with gaze onset occurring relatively later with respect to head onset. Following the injections, the head contributed slightly more to the gaze shift. These results suggest that head movements (with and without gaze shifts) can be controlled by pathways that do not involve SC.
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Affiliation(s)
- Mark M G Walton
- Department of Otolaryngology, Eye and Ear Institute, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA
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42
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Zhong MK, Duan YC, Chen AD, Xu B, Gao XY, De W, Zhu GQ. Paraventricular nucleus is involved in the central pathway of cardiac sympathetic afferent reflex in rats. Exp Physiol 2008; 93:746-53. [PMID: 18281391 DOI: 10.1113/expphysiol.2007.041632] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Our previous studies have shown that angiotensin II and reactive oxygen species in the paraventricular nucleus (PVN) modulate the cardiac sympathetic afferent reflex (CSAR). The present study was designed to demonstrate more conclusively that the PVN is an important component of the central neurocircuitry of the CSAR. In anaesthetized Sprague-Dawley rats with sinoaortic denervation and cervical vagotomy, renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were continuously recorded. The CSAR was evaluated by the response of the RSNA to epicardial application of bradykinin or capsaicin. Bilateral microinjection of the anaesthetic, lignocaine, into the PVN abolished the CSAR without significant effects on the baseline RSNA and MAP, while l-glutamate, which excites the neurons in the PVN, enhanced the CSAR and increased the baseline RSNA and MAP. Bilateral electrolytic lesions of the PVN irreversibly abolished the CSAR without significant effects on the baseline RSNA and MAP. Bilateral selective lesions of the neurons in the PVN with kainic acid induced rapid and great increases in both RSNA and MAP which returned to nearly normal levels in 60 min. At the 90th minute after kainic acid, epicardial application of bradykinin or capsaicin failed to induce the CSAR. These results indicate that inhibition or lesion of the PVN abolishes the CSAR, but excitation of the neurons in the PVN enhances the CSAR, suggesting that the PVN is an important component of the central neurocircuitry of the CSAR.
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Affiliation(s)
- Ming-Kui Zhong
- Department of Physiology, Nanjing Medical University, Nanjing 210029, China
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43
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Li CS, Mao L, Cho YK. Taste-responsive neurons in the nucleus of the solitary tract receive gustatory information from both sides of the tongue in the hamster. Am J Physiol Regul Integr Comp Physiol 2007; 294:R372-81. [PMID: 18077506 DOI: 10.1152/ajpregu.00791.2007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Taste receptors on the left and right sides of the anterior tongue are innervated by chorda tympani (CT) fibers, which carry taste information to the ipsilateral nucleus of the solitary tract (NST). Although the anterior tongue is essential for taste, patients with unilateral CT nerve damage often report no subjective change in their taste experience. The standing theory that explains the taste constancy is the "release of inhibition", which hypothesizes that within the NST there are inhibitory interactions between inputs from the CT and glossopharyngeal nerves and that the loss of taste information from the CT is compensated by a release of inhibition on the glossopharyngeal nerve input. However, the possibility of compensation by taste input from the other side of the tongue has never been investigated in rodents. We recorded from 95 taste-responsive neurons in the NST and examined their responsiveness to stimulation of the contralateral CT. Forty-six cells were activated, mostly with excitatory responses (42 cells). Activation of NST cells induced by contralateral CT stimulation was blocked by microinjection of lidocaine into the contralateral NST but was not affected by anesthetization of the contralateral parabrachial nuclei (PbN). In addition, the NST cells that were activated by contralateral CT stimulation showed reduced responsiveness to taste stimulation after microinjection of lidocaine into the contralateral NST. These results demonstrate that nearly half of the taste neurons in the NST receive gustatory information from both sides of the tongue. This "cross talk" between bilateral NST may also contribute to the "taste constancy".
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Affiliation(s)
- Cheng-Shu Li
- Department of Anatomy, Southern Illinois University School of Medicine, Life Science III, 1135 Lincoln Drive, Carbondale, IL 62901, USA.
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Fernandes KBP, Tavares RF, Pelosi GG, Corrêa FMA. The paraventricular nucleus of hypothalamus mediates the pressor response to noradrenergic stimulation of the medial prefrontal cortex in unanesthetized rats. Neurosci Lett 2007; 426:101-5. [PMID: 17890005 DOI: 10.1016/j.neulet.2007.08.063] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 08/31/2007] [Accepted: 08/31/2007] [Indexed: 10/22/2022]
Abstract
The medial prefrontal cortex (MPFC) is a structure that is also involved in cardiovascular modulation. The injection of norepinephrine (NE) into the prelimbic (PL) area of the MPFC of unanesthetized rats evokes a pressor response which is mediated by acute vasopressin release. Vasopressin is synthesized by magnocellular cells of the paraventricular (PVN) and supraoptic nucleus (SON) of the hypothalamus. In the present study, we endeavored to determine which vasopressin-synthesizing hypothalamic nucleus is involved in the pressor pathway activated after NE injection into the PL area of the MPFC. We report here that lidocaine microinjection into the SON did not change the pressor response evoked by NE injection into the PL. However, the response to NE was blocked by prior injection of lidocaine or CoCl(2) into the PVN, indicating that this area is responsible for the mediation of this pressor response. A neuroanatomic experiment in which the neuronal tracer biotinylated dextran amine (BDA) was microinjected into the MPFC showed a lack of axons or neuronal cell bodies in the PVN, indicating that there are no direct connections between the PL area of the MPFC and the PVN. The results suggest that the PVN is involved in the mediation of the pressor response to NE in the PL area and that this pathway must relay in other brain structures before reaching the PVN.
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45
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Pelosi GG, Resstel LBM, Corrêa FMA. Dorsal periaqueductal gray area synapses modulate baroreflex in unanesthetized rats. Auton Neurosci 2007; 131:70-6. [PMID: 16914391 DOI: 10.1016/j.autneu.2006.07.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 07/04/2006] [Accepted: 07/10/2006] [Indexed: 10/24/2022]
Abstract
The dorsal portion of the periaqueductal gray area (dPAG) is involved in behavioral and cardiovascular control. We report the effect of acute and reversible dPAG blockade by local microinjection of either lidocaine or CoCl2 on the baroreflex response of unanesthetized rats. Acute and reversible blockade evoked by lidocaine microinjection into the dPAG did not affect the bradycardic response to mean arterial pressure (MAP) increases evoked by i.v. infusion of phenylephrine. However, lidocaine increased baroreflex gain and tachycardic reflex in response to MAP decreases evoked by i.v. infusion of sodium nitroprusside, thus suggesting an action on the sympathetic component of the baroreflex. The effects of dPAG synapses blockade caused by CoCl2 were similar to those observed after lidocaine microinjection. CoCl2 microinjection also increased baroreflex gain and tachycardiac responses to MAP decreases without affecting the parasympathetic baroreflex component. In conclusion, our data point to a dPAG tonic inhibitory involvement in baroreflex control, specifically modulating the sympathetic baroreflex component. Temporary dPAG ablation by local microinjection of lidocaine increased the sympathetic baroreflex component. Because CoCl2 microinjection had similar effects on the baroreflex, this modulation involves local synaptic neurotransmission within the dPAG.
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Affiliation(s)
- G G Pelosi
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, 14040-900, Ribeirão Preto, São Paulo, Brazil
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46
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Tavares RF, Corrêa FMA. Role of the medial prefrontal cortex in cardiovascular responses to acute restraint in rats. Neuroscience 2006; 143:231-40. [PMID: 16938408 DOI: 10.1016/j.neuroscience.2006.07.030] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Revised: 05/15/2006] [Accepted: 07/22/2006] [Indexed: 10/24/2022]
Abstract
The medial prefrontal cortex (mPFC) modulates neurovegetative and behavioral responses, being involved in memory, attention, motivational and executive processes. There is evidence indicating that mPFC modulates cardiovascular correlates of behavioral responses to stressful stimuli. Acute restraint is an unavoidable stress situation that evokes marked and sustained cardiovascular changes, characterized by elevated blood pressure (BP) and intense heart rate (HR) increase. We presently report effects of mPFC pharmacological manipulations on BP and HR responses evoked by acute restraint in rats. Bilateral microinjection of 200 nl of the unspecific synaptic blocker CoCl2 (1 mM) in the mPFC prelimbic area (PL) increased HR response to acute restraint, without significant effect on the BP response. This result indicates that PL synaptic mechanisms have an inhibitory influence on restraint-evoked HR changes. Injections of the non-selective glutamatergic receptor antagonist kynurenic acid (0.02 M) or the selective N-methyl-d-aspartic acid (NMDA) receptor glutamatergic antagonist (LY235959) (0.02 M) caused effects similar to cobalt, suggesting that local glutamatergic neurotransmission and NMDA receptors mediate the PL inhibitory influence on restraint-related HR responses. Pretreatment with the non-non-N-methyl-D-aspartic acid glutamatergic antagonist glutamatergic antagonist glutamatergic receptor antagonist NBQX (0.02 M) did not affect restraint-related cardiovascular responses, reinforcing the idea that NMDA receptors mediate PL-related inhibitory influence. Pretreatment with the glutamatergic-receptor antagonists did not affect baseline BP or HR values. I.v. pretreatment with the quaternary ammonium anticholinergic drug homatropine methyl bromide (0.2 mg/kg) also increased the restraint-related HR response to values similar to those observed after treatment with kynurenic acid or LY235959, thus, suggesting that PL inhibitory influence on restraint-evoked heart rate increase could be related to increased parasympathetic activity. This dose of homatropine had no significant effects on baseline BP or HR values. Results suggest a PL inhibitory influence on restraint-evoked HR increase. They also indicate that local NMDA receptors involved in parasympathetic activation mediate PL inhibitory influence on restraint-evoked HR increase.
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Affiliation(s)
- R F Tavares
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ave. Bandeirantes, 3900-14049-900 Ribeirão Preto, São Paulo, Brazil
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Teixeira CM, Pomedli SR, Maei HR, Kee N, Frankland PW. Involvement of the anterior cingulate cortex in the expression of remote spatial memory. J Neurosci 2006; 26:7555-64. [PMID: 16855083 PMCID: PMC6674278 DOI: 10.1523/jneurosci.1068-06.2006] [Citation(s) in RCA: 212] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although the hippocampus plays a crucial role in the formation of spatial memories, as these memories mature they may become additionally (or even exclusively) dependent on extrahippocampal structures. However, the identity of these extrahippocampal structures that support remote spatial memory is currently not known. Using a Morris water-maze task, we show that the anterior cingulate cortex (ACC) plays a key role in the expression of remote spatial memories in mice. To first evaluate whether the ACC is activated after the recall of spatial memory, we examined the expression of the immediate early gene, c-fos, in the ACC. Fos expression was elevated after expression of a remote (1 month old), but not recent (1 d old), water-maze memory, suggesting that ACC plays an increasingly important role as a function of time. Consistent with the gene expression data, targeted pharmacological inactivation of the ACC with the sodium channel blocker lidocaine blocked expression of remote, but spared recent, spatial memory. In contrast, inactivation of the dorsal hippocampus disrupted expression of spatial memory, regardless of its age. We further showed that inactivation of the ACC blocked expression of remote spatial memory in two different mouse strains, after training with either a hidden or visible platform in a constant location, and using the AMPA receptor antagonist CNQX. Together, our data provide evidence that circuits supporting spatial memory are reorganized in a time-dependent manner, and establish that activity in neurons intrinsic to the ACC is critical for processing remote spatial memories.
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Dringenberg HC, Sparling JS, Frazer J, Murdoch J. Generalized cortex activation by the auditory midbrain: Mediation by acetylcholine and subcortical relays. Exp Brain Res 2006; 174:114-23. [PMID: 16575576 DOI: 10.1007/s00221-006-0427-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2005] [Accepted: 02/28/2006] [Indexed: 10/24/2022]
Abstract
The inferior colliculus (IC) is a critical component of the ascending projection system carrying auditory information from the brainstem to the forebrain. Recent evidence indicates that, in addition to its role in auditory processing, the IC can exert a generalized, modulatory effect on the forebrain by activating the neocortical electrocorticogram (ECoG). Given the sparse direct projections from the IC to the cortex, it appears that the effect of the IC to produce ECoG activation is indirect, mediated by one or several neuromodulatory systems that have diffuse access to the entire cortical mantle. However, the anatomical relays that permit the IC to influence cortical activity have not been elucidated. In the present experiments, electrical stimulation of the IC suppressed slow, large amplitude oscillations in the ECoG of urethane anesthetized rats, replacing them with higher-frequency cortical activation. This effect was blocked by the muscarinic receptor antagonist scopolamine (0.5-1.0 mg/kg, i.p.), suggestive of a critical role of acetylcholine (ACh) release. Consistent with this hypothesis, localized lidocaine infusions (2%, 1 microl) into the cholinergic basal forebrain complex strongly reduced ECoG activation elicited by IC stimulation. To identify additional relays between the IC and basal forebrain, the effects of lidocaine infusions into the superior colliculus, medial prefrontal cortex, midline thalamus, and dorsal raphe were also studied. Inactivation of the superior colliculus and dorsal raphe reduced IC-induced activation, while prefrontal cortex and thalamic infusions were ineffective. Concurrent basal forebrain and raphe inactivation produced effects similar to that of inactivation of the basal forebrain alone, suggesting that these two areas are arranged in series, rather than acting as independent, parallel pathways. These results suggest that the ability of the IC to induce ECoG activation is mediated, in large parts, by the basal forebrain cholinergic system. Consistent with anatomical evidence, the superior colliculus and dorsal raphe appear to provide important links to functionally connect the IC to the basal forebrain, allowing the IC to indirectly access the entire cortical mantle and enhance processing in neocortical networks.
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Affiliation(s)
- Hans C Dringenberg
- Department of Psychology, Queen's University, K7L 3N6, Kingston, ON, Canada.
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Satoh Y, Ishizuka K, Oskutyte D, Murakami T. Role of the parvicellular reticular formation in facilitating the jaw-opening reflex in rats by stimulation of the red nucleus. Brain Res 2006; 1083:145-50. [PMID: 16529727 DOI: 10.1016/j.brainres.2006.02.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 01/31/2006] [Accepted: 02/02/2006] [Indexed: 01/01/2023]
Abstract
In a previous study, we have shown that electrical and chemical stimulation of the red nucleus (RN) facilitates the jaw-opening reflex (JOR). The RN sends projection fibers bilaterally, with contralateral dominance, to the part of the parvicellular reticular formation (RFp) containing premotor neurons projecting to the trigeminal motor nucleus. This implies that RN-induced facilitation of the JOR might be mediated via last-order neurons in the RFp. Here, we address this issue by investigating whether microinjection of lidocaine or l-glutamate into the RFp affects RN-induced modulation of the JOR. Experiments were performed on rats anesthetized with urethane-chloralose. The JOR was evoked by electrical stimulation of the inferior alveolar (IA) nerve and was recorded as an electromyographic response from the anterior belly of the digastric muscle. Conditioning stimulation was delivered unilaterally to the RN 12 ms before the IA test stimulation. We found that local injections of 2% lidocaine (0.5 microl) into the RFp, contralateral to the RN, significantly (P < 0.05) reduce RN-induced facilitation of the JOR, whereas corresponding injections of 0.1 mM l-glutamate (0.5 microl) significantly (P < 0.05) increase it. These results suggest that the facilitatory effect of RN stimulation on the JOR is mediated partly by a relay in the RFp.
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Affiliation(s)
- Yoshihide Satoh
- Department of Physiology, The Nippon Dental University School of Dentistry at Niigata, 1-8 Hamaura-cho, Niigata 951-8580, Japan.
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Pereira de Vasconcelos A, Klur S, Muller C, Cosquer B, Lopez J, Certa U, Cassel JC. Reversible inactivation of the dorsal hippocampus by tetrodotoxin or lidocaine: A comparative study on cerebral functional activity and motor coordination in the rat. Neuroscience 2006; 141:1649-63. [PMID: 16797129 DOI: 10.1016/j.neuroscience.2006.05.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Revised: 04/16/2006] [Accepted: 05/07/2006] [Indexed: 11/26/2022]
Abstract
Reversible inactivation of the hippocampus by lidocaine or tetrodotoxin is used to investigate implications of this structure in memory processes. Crucial points related to such inactivation are the temporal and spatial extents of the blockade. We compared effects of intrahippocampal infusions of commonly-used doses of lidocaine (5 or 10 mug) or tetrodotoxin (5 or 10 ng) in rats at two post-infusion delays (5 or 30 min), using 2-deoxyglucose autoradiography to visualize local cerebral glucose metabolism, and beam-walking performance to assess motor coordination. In addition, memory retrieval was evaluated in a water maze after bilateral infusions of 10 mug lidocaine. A unilateral tetrodotoxin infusion induced dose- and time-dependent reductions of 2-deoxyglucose uptake in the vicinity of the infusion site (dorsal hippocampus: -29% to -67%) and in other ipsi- and contralateral brain regions (ventral hippocampus, lateral thalamus, cortical regions). The maximal effect was at 10 ng, at the delay of 30 min between the tetrodotoxin infusion and the 2-deoxyglucose injection. Uni- and bilateral infusions of tetrodotoxin induced dramatic motor coordination deficits. Conversely, lidocaine reduced 2-deoxyglucose uptake (-19%) in the dorsal hippocampus only at 10 mug, with weak extrahippocampal effects. Whether infused uni- or bilaterally and regardless of the dose, lidocaine did not alter motor coordination. When infused bilaterally, however, 10 microg of lidocaine impaired short-term retrieval of spatial information in a water maze. Because lidocaine i) induced a weak though significant functional blockade mainly restricted to the infusion site, ii) had no consequences on motor coordination and, nevertheless iii) altered short-term spatial memory retrieval, we conclude that acute intrahippocampal infusions of lidocaine may offer some advantages over tetrodotoxin at the doses used herein.
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Affiliation(s)
- A Pereira de Vasconcelos
- LN2C FRE 2855, Université Louis Pasteur, ULP/CNRS, Institut Fédératif de Recherche IFR 37, GDR CNRS 2905, 12 rue Goethe, F 67000 Strasbourg, France
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