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Circadian rhythm influences naloxone induced morphine withdrawal and neuronal activity of lateral paragigantocellularis nucleus. Behav Brain Res 2021; 414:113450. [PMID: 34265318 DOI: 10.1016/j.bbr.2021.113450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 06/10/2021] [Accepted: 07/08/2021] [Indexed: 11/23/2022]
Abstract
Investigations have shown that the circadian rhythm can affect the mechanisms associated with drug dependence. In this regard, we sought to assess the negative consequence of morphine withdrawal syndrome on conditioned place aversion (CPA) and lateral paragigantocellularis (LPGi) neuronal activity in morphine-dependent rats during light (8:00-12:00) and dark (20:00-24:00) cycles. Male Wistar rats (250-300 g) were received 10 mg/kg morphine or its vehicle (Saline, 2 mL/kg/12 h, s.c.) in 13 consecutive days for behavioral assessment tests. Then, naloxone-induced conditioned place aversion and physical signs of withdrawal syndrome were evaluated during light and dark cycles. In contrast to the behavioral part, we performed in vivo extracellular single-unit recording for investigating the neural response of LPGi to naloxone in morphine-dependent rats on day 10 of morphine/saline exposure. Results showed that naloxone induced conditioned place aversion in both light and dark cycles, but the CPA score during the light cycle was larger. Moreover, the intensity of physical signs of morphine withdrawal syndrome was more severe during the light cycle (rest phase) compare to the dark one. In electrophysiological experiments, results indicated that naloxone evoked both excitatory and inhibitory responses in LPGi neurons and the incremental effect of naloxone on LPGi activity was stronger in the light cycle. Also, the neurons with the excitatory response exhibited higher baseline activity in the dark cycle, but the neurons with the inhibitory response showed higher baseline activity in the light cycle. Interestingly, the baseline firing rate of neurons recorded in the light cycle was significantly different in response (excitatory/inhibitory) -dependent manner. We concluded that naloxone-induced changes in LPGi cellular activity and behaviors of morphine-dependent rats can be affected by circadian rhythm and the internal clock.
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Azadi M, Gompf HS, Azizi H. Paternal exposure to morphine during adolescence potentiates morphine withdrawal in male offspring: Involvement of the lateral paragigantocellularis nucleus. J Psychopharmacol 2020; 34:1289-1299. [PMID: 33112218 DOI: 10.1177/0269881120953993] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Opiate exposure during adolescence perturbs the brain's maturation process and potentially confers long-term adverse consequences, not only in exposed individuals but also in their posterity. Here, we investigate the outcomes of adolescent paternal morphine exposure on morphine withdrawal profile in male offspring. METHODS Male Wistar rats were chronically subjected to 10 days of an escalating regimen of morphine during adolescence. After a 20-day washout period, adult males were allowed to copulate with naïve females. The adult male offspring were tested for somatic and affective components of naloxone-precipitated morphine withdrawal using conditioned place aversion. Moreover, electrical activity of the lateral paragigantocellularis (LPGi) nucleus, which is involved in development of opiate dependence, was recorded in response to a challenge dose of morphine via extracellular single-unit recordings. RESULTS Morphine-sired offspring exhibited augmented expression of naloxone-induced somatic and affective signs of opiate withdrawal compared to the control saline-sired counterparts. In vivo recording revealed that LPGi neurons displayed heterogeneous responses (inhibitory, excitatory, and no change) to acute morphine administration in both morphine- and saline-sired animals. The morphine-induced discharge inhibition was potentiated in morphine-sired offspring. However, the extent of discharge excitation in response to morphine did not reach significance in these subjects. Moreover, the lack of alteration in maternal behavior toward morphine-sired offspring indicates that this is due to germline-dependent transmission of epigenetic traits across generations. CONCLUSIONS Preconception paternal exposure to morphine during adolescence potentiates opiate withdrawal signs in male offspring which is mediated, at least in part, by epigenetic alteration of LPGi-related brain circuitry.
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Affiliation(s)
- Maryam Azadi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Heinrich S Gompf
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, USA
| | - Hossein Azizi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
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Adolescent nicotine challenge promotes the future vulnerability to opioid addiction: Involvement of lateral paragigantocellularis neurons. Life Sci 2019; 234:116784. [DOI: 10.1016/j.lfs.2019.116784] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 08/11/2019] [Accepted: 08/20/2019] [Indexed: 02/03/2023]
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Chronic adolescent morphine exposure alters the responses of lateral paragigantocellular neurons to acute morphine administration in adulthood. Brain Res Bull 2018; 137:178-186. [DOI: 10.1016/j.brainresbull.2017.12.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/20/2017] [Accepted: 12/07/2017] [Indexed: 11/19/2022]
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Role of orexin type-1 receptors in paragiganto-coerulear modulation of opioid withdrawal and tolerance: A site specific focus. Neuropharmacology 2017; 126:25-37. [DOI: 10.1016/j.neuropharm.2017.08.024] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 08/13/2017] [Accepted: 08/16/2017] [Indexed: 11/21/2022]
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Fatahi Z, Zibaii MI, Haghparast A. Effect of acute and subchronic stress on electrical activity of basolateral amygdala neurons in conditioned place preference paradigm: An electrophysiological study. Behav Brain Res 2017; 335:19-25. [DOI: 10.1016/j.bbr.2017.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/28/2017] [Accepted: 08/05/2017] [Indexed: 01/19/2023]
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Farbood Y, Shabani S, Sarkaki A, Mard SA, Ahangarpour A, Khorsandi L. Peripheral and central administration of T3 improved the histological changes, memory and the dentate gyrus electrophysiological activity in an animal model of Alzheimer's disease. Metab Brain Dis 2017; 32:693-701. [PMID: 28124751 DOI: 10.1007/s11011-016-9947-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 12/30/2016] [Indexed: 12/13/2022]
Abstract
The amyloid beta (Aβ) induced Alzheimer's disease (AD) is associated with formation the amyloid plaques, cognitive impairments and decline in spontaneous discharge of neurons. In the current study, we evaluated the effect of subcutaneous (S. C) and intrahippocampal (I. H) administrations of triiodothyronine (T3) on the histological changes, memory and the dentate gyrus (DG) electrophysiological activity in an animal model of AD. Eighty adult male Wistar rats (250-300 g) were divided randomly into five groups: Sham-Operated (Sh-O), AD + Vehicle (S. C), AD + Vehicle (I. H), AD+ T3 (S. C) and AD + T3 (I. H). In order to induce animal model of AD, Aβ (10 ng/μl, bilaterally) were injected intrahippocampally. Rats were treated with T3 and/or normal saline for 10 days. Passive avoidance and spatial memory were evaluated in shuttle box apparatus and Morris water maze, respectively. Neuronal single unit recording was assessed from hippocampal DG. The percent of total time that animals spent in target quarter, the mean latency time (sec), the step through latency and the average number of spikes/bin were decreased significantly in AD rats compared with the Sh-O group (p < 0.001) and were increased significantly in AD groups that have received T3 (S. C and I. H) in compared with AD group (p < 0.01, p < 0.001). Also, formation of amyloid plaques was decreased in AD rats treated with T3.The results showed that T3 injection (S. C and I. H), by reduction of neural damage and increment of neuronal spontaneous activity improved the memory deficits in Aβ-induced AD rats.
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Affiliation(s)
- Yaghoob Farbood
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
| | - Sahreh Shabani
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
| | - Alireza Sarkaki
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Seyyed Ali Mard
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Akram Ahangarpour
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Layasadat Khorsandi
- Cellular and Molecular Research Center, Department of Anatomical Sciences, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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Shabani S, Sarkaki A, Ali Mard S, Ahangarpour A, Khorsandi L, Farbood Y. Central and peripheral administrations of levothyroxine improved memory performance and amplified brain electrical activity in the rat model of Alzheimer's disease. Neuropeptides 2016; 59:111-116. [PMID: 27640349 DOI: 10.1016/j.npep.2016.09.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/09/2016] [Accepted: 09/08/2016] [Indexed: 11/26/2022]
Abstract
Alzheimer's disease (AD) is associated with cognitive impairments and a decline in the spontaneous neuronal discharge. In the current study, we evaluated the effect of subcutaneous (S.C.) and intrahippocampal (I.H.) administrations of levothyroxine (LT-4) on the passive avoidance and spatial memory, as well as electrophysiological activity in an animal model of AD. One hundred-sixty male Wistar rats were divided into two main groups. The S.C. group included two Sham and four AD (vehicle or L-T4 25, 50 & 100μg/kg); and the I.H. had consisted of two Sham and two AD (vehicle or L-T4 10μg/kg) subgroups. To make an animal model of AD, amyloid beta (Aβ) plus ibotenic acid (Ibo) were injected I.H. Rats were treated with L-T4 and/or normal saline for ten days. Passive avoidance and spatial memory were evaluated in shuttle box and Morris water maze, respectively. Neuronal single unit recording was assessed from hippocampal dentate gyrus (DG). Results showed that the mean latency time (s) increased significantly (p<0.001) in AD animals and decreased significantly in both S.C. and I.H. L-T4 injected AD animals, compared with the AD group (p<0.001). The percentage of total time that animals spent in goal quarter and the step through latency decreased significantly in AD rats (p<0.001) and increased significantly in both S.C. and I.H. L-T4 injected AD animals in comparison with the AD group (p<0.01, p<0.001). Data showed that the average number of spikes/bin significantly decreased in the AD group (p<0.001). The S.C. and I.H. L-T4 injections in AD rats significantly increased the spike rate in comparison to the AD group (p<0.001). In conclusion, both S.C. and I.H. injections of L-T4 alleviated memory deficits and spontaneous neuronal activity in Aβ-induced AD rats. Also, I.H. microinjection of L-T4 had more beneficial effects on memory and neuronal electrophysiological activity in comparison to S.C. administration.
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Affiliation(s)
- Sahreh Shabani
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Alireza Sarkaki
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Seyyed Ali Mard
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Akram Ahangarpour
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Layasadat Khorsandi
- Cellular and Molecular Research Center, Department of Anatomical Sciences, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Yaghoob Farbood
- Physiology Research Center, Department of Physiology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
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Farbood Y, Sarkaki A, Khalaj L, Khodagholi F, Badavi M, Ashabi G. Targeting Adenosine Monophosphate-Activated Protein Kinase by Metformin Adjusts Post-Ischemic Hyperemia and Extracellular Neuronal Discharge in Transient Global Cerebral Ischemia. Microcirculation 2016. [PMID: 26213885 DOI: 10.1111/micc.12224] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE I/R and its subsequent reactive hyperemia results in different adverse effects such as brain edema and BBB disruption. AMPK activation has been perceived as one of the target factors for I/R treatment. We investigated the effect of Met (an AMPK activator) on some physiological parameters including vascular responses, hyperemia, BBB disruption, and electrophysiological activity following tGCI. METHODS Rats were pretreated with Met for two weeks and CC was administered half an hour before tGCI. Brain vascular responses, hyperemia, BBB disruption, and electrophysiological activity were evaluated following the ischemia. RESULTS Met attenuated BBB disruption and reactive hyperemia in tGCI rats compared with the untreated I/R rats (p < 0.001). Met administration along with CC in the ischemic rats reversed the beneficial effects of Met on BBB disruption and reactive hyperemia (p < 0.001). Electrophysiological records indicated that Met increased spike rates in the ischemic rats comparing with I/R rats (p < 0.001), whereas, CC administration blocked the beneficial effects of Met on the neuronal discharges (p < 0.05). CONCLUSION We established a regulatory role for AMPK in vascular and electrophysiological responses to tGCI. Studies are ongoing to determine if activation of AMPK in the reperfusion period would offer similar protection.
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Affiliation(s)
- Yaghoob Farbood
- Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Alireza Sarkaki
- Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Leila Khalaj
- Medical School, Alborz University of Medical Sciences, Alborz, Iran
| | - Fariba Khodagholi
- Neuroscience Research Center, ShahidBeheshti University of Medical Sciences, Tehran, Iran.,Neurobiology Research Center, ShahidBeheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Badavi
- Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Ghorbangol Ashabi
- Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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Rostami A, Shahani M, Zarrindast MR, Semnanian S, Rahmati Roudsari M, Rezaei Tavirani M, Hasanzadeh H. Effects of 3 Hz and 60 Hz Extremely Low Frequency Electromagnetic Fields on Anxiety-Like Behaviors, Memory Retention of Passive Avoidance and Electrophysiological Properties of Male Rats. J Lasers Med Sci 2016; 7:120-5. [PMID: 27330708 DOI: 10.15171/jlms.2016.20] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
INTRODUCTION The effects of electromagnetic fields on biological organisms have been a controversial and also interesting debate over the past few decades, despite the wide range of investigations, many aspects of extremely low frequency electromagnetic fields (ELF/EMFs) effects including mechanism of their interaction with live organisms and also their possible biological applications still remain ambiguous. In the present study, we investigated whether the exposures of ELF/EMF with frequencies of 3 Hz and 60 Hz can affect the memory, anxiety like behaviors, electrophysiological properties and brain's proteome in rats. METHODS Male rats were exposed to 3 Hz and 60 Hz ELF/EMFs in a protocol consisting of 2 cycles of 2 h/day exposure for 4 days separated with a 2-day interval. Short term memory and anxiety like behaviors were assessed immediately, 1 and 2 weeks after the exposures. Effects of short term exposure were also assessed using electrophysiological approach immediately after 2 hours exposure. RESULTS Behavioral test revealed that immediately after the end of exposures, locomotor activity of both 3 Hz and 60 Hz exposed groups significantly decreased compared to sham group. This exposure protocol had no effect on anxiety like behavior during the 2 weeks after the treatment and also on short term memory. A significant reduction in firing rate of locus coeruleus (LC) was found after 2 hours of both 3 Hz and 60 Hz exposures. Proteome analysis also revealed global changes in whole brain proteome after treatment. CONCLUSION Here, some evidence regarding the fact that such exposures can alter locomotor activity and neurons firing rate in male rats were presented.
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Affiliation(s)
- Amin Rostami
- Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Minoo Shahani
- Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Saeed Semnanian
- Department of Physiology, School of Medical Sciences, Tarbiat Modarres University, Tehran, Iran
| | | | | | - Hadi Hasanzadeh
- Cancer Research Center and Department of Medical Physics, Semnan University of Medical Sciences, Semnan, Iran
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Direct Facilitatory Role of Paragigantocellularis Neurons in Opiate Withdrawal-Induced Hyperactivity of Rat Locus Coeruleus Neurons: An In Vitro Study. PLoS One 2015; 10:e0134873. [PMID: 26230639 PMCID: PMC4521852 DOI: 10.1371/journal.pone.0134873] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 07/14/2015] [Indexed: 11/19/2022] Open
Abstract
Studies have shown that following opiate withdrawal, the spontaneous discharge rate of locus coeruleus (LC) neurons remarkably increases. Combination of intrinsic mechanisms with extrinsic excitatory modulations mediates the withdrawal-induced hyperactivity of LC neurons. The nucleus paragigantocellularis (PGi) provides the main excitatory inputs to LC and plays a pivotal role in opiate withdrawal. In the present study the direct facilitatory role of PGi on opiate withdrawal-induced hyperactivity of LC neurons was investigated using a newly developed brain slice, containing both LC and PGi. HRP retrograde neuronal tracing was used to verify the existence of both LC and PGi neurons in the developed slice. The spontaneous discharge rate (SDR), resting membrane potential (RMP) and spontaneous excitatory post-synaptic currents (sEPSCs) were recorded in LC neurons using whole cell patch clamp recording. Results showed that the net SDR and the net RMP of LC neurons in slices containing both LC and PGi neurons are significantly higher than slices lacking intact (uncut) PGi inputs. Also, the frequency of sEPSCs in those LC neurons receiving PGi inputs significantly increased compared to the slices containing no intact PGi inputs. Altogether, our results propose that increase in PGi-mediated excitatory transmission might facilitate the opiate withdrawal-induced hyperactivity of LC neurons.
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Riahi E, Arezoomandan R, Fatahi Z, Haghparast A. The electrical activity of hippocampal pyramidal neuron is subjected to descending control by the brain orexin/hypocretin system. Neurobiol Learn Mem 2015; 119:93-101. [DOI: 10.1016/j.nlm.2015.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 12/23/2014] [Accepted: 02/03/2015] [Indexed: 11/16/2022]
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Reversal of opioid overdose syndrome in morphine-dependent rats using buprenorphine. Toxicol Lett 2015; 232:590-4. [DOI: 10.1016/j.toxlet.2014.12.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 12/09/2014] [Accepted: 12/10/2014] [Indexed: 11/19/2022]
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Ghaemi-Jandabi M, Azizi H, Semnanian S. Blockade of orexin type 1 receptors inhibits the development of morphine tolerance in lateral paragigantocellularis nucleus: An electrophysiological approach. Brain Res 2014; 1578:14-22. [DOI: 10.1016/j.brainres.2014.06.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/06/2014] [Accepted: 06/27/2014] [Indexed: 11/26/2022]
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Haghparast A, Gheitasi IP, Lashgari R. Involvement of glutamatergic receptors in the nucleus cuneiformis in modulating morphine-induced antinociception in rats. Eur J Pain 2012; 11:855-62. [PMID: 17291798 DOI: 10.1016/j.ejpain.2006.12.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2006] [Revised: 12/29/2006] [Accepted: 12/29/2006] [Indexed: 11/30/2022]
Abstract
The nucleus cuneiformis (CnF), located just ventrolateral to the periaqueductal gray, is part of the descending pain modulatory system. Neurons in the CnF project to medullary nucleus raphe magnus (NRM), which plays an important role on pain modulation. In this study, we investigated the effect of microinjection of the non-competitive NMDA receptor antagonist MK-801, the competitive NMDA receptor antagonist AP-7, and the kainate/AMPA receptor antagonist DNQX, alone or in combination with morphine into the nucleus cuneiformis on morphine-induced analgesia to understand the role of glutamatergic receptors in the modulating activity of morphine. Antinociception was assessed with the tail-flick test. Morphine (10, 20, 40 microg in 0.5 microl saline) had an antinociceptive effect, increasing tail-flick latency in a dose-dependent manner. Microinjection of MK-801 (10 microg/0.5 microl saline) and AP7 (3 microg/0.5 microl saline) prior to morphine microinjection (10 microg/0.5 microl saline) attenuated the antinociceptive effects of morphine, whereas DNQX (0.5 microg/0.5 microl saline) showed a partial antinociceptive effect and potentiated the analgesic effect of morphine. These results indicated that the NMDA receptor partially potentiates the antinociceptive effect of morphine. Our results suggest that NMDA but not non-NMDA receptors are involved in the antinociception produced by morphine in the CnF. The non-NMDA receptors in this area may have a facilitatory effect on nociceptive transmission. The fact that morphine's effect was potentiated by NMDA receptor suggests that projection neurons within the CnF are under tonic, glutamatergic input and when the influence of this input is blocked, the descending inhibitory system is inactivated.
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Affiliation(s)
- Abbas Haghparast
- Department of Physiology and Pharmacology, School of Medicine and Neuroscience Research Center, Kerman University of Medical Sciences, P.O. Box 444, Kerman, Iran.
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Kleczkowska P, Kosson P, Ballet S, Van den Eynde I, Tsuda Y, Tourwé D, Lipkowski AW. PK20, a new opioid-neurotensin hybrid peptide that exhibits central and peripheral antinociceptive effects. Mol Pain 2010; 6:86. [PMID: 21134256 PMCID: PMC3017538 DOI: 10.1186/1744-8069-6-86] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 12/06/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The clinical treatment of various types of pain relies upon the use of opioid analgesics. However most of them produce, in addition to the analgesic effect, several side effects such as the development of dependence and addiction as well as sedation, dysphoria, and constipation. One solution to these problems are chimeric compounds in which the opioid pharmacophore is hybridized with another type of compound to incease antinociceptive effects. Neurotensin-induced antinociception is not mediated through the opioid system. Therefore, hybridizing neurotensin with opioid elements may result in a potent synergistic antinociceptor. RESULTS Using the known structure-activity relationships of neurotensin we have synthesized a new chimeric opioid-neurotensin compound PK20 which is characterized by a very strong antinociceptive potency. The observation that the opioid antagonist naltrexone did not completely reverse the antinociceptive effect, indicates the partial involvement of the nonopioid component in PK20 in the produced analgesia. CONCLUSIONS The opioid-neurotensin hybrid analogue PK20, in which opioid and neurotensin pharmacophores overlap partially, expresses high antinociceptive tail-flick effects after central as well as peripheral applications.
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Affiliation(s)
- Patrycja Kleczkowska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego Street 5, 02106 Warsaw, Poland
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Zhu H, Zhou W. Discharge activities of neurons in the nucleus paragigantocellularis during the development of morphine tolerance and dependence: a single unit study in chronically implanted rats. Eur J Pharmacol 2010; 636:65-72. [PMID: 20371225 PMCID: PMC2866837 DOI: 10.1016/j.ejphar.2010.03.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Revised: 02/24/2010] [Accepted: 03/14/2010] [Indexed: 11/15/2022]
Abstract
The nucleus paragigantocellularis (PGi) has been proposed to play a role in opiate dependence/withdrawal. In the present study, we examined the discharge activity of PGi neurons before and after the development of morphine tolerance/dependence in rats. A multi-wire electrode was chronically implanted in the PGi, which allowed us to monitor the effects of both acute and chronic morphine treatments on the activity of PGi neurons recorded from the same site. We found that acute morphine excited, inhibited or had no effect on 36%, 35% or 29% of PGi neurons (N=556), respectively. After 3 days of continuous morphine infusion, which led to morphine tolerance/dependence, the firing rates of both excitatory and inhibitory PGi neurons returned to pre-morphine treatment levels, indicating that the PGi neurons developed tolerance to both excitatory and inhibitory effects of morphine. Naltrexone-precipitated withdrawal from chronic morphine treatment also induced heterogeneous responses in the PGi. On a site-by-site basis, most of the sites that showed excitatory response to acute morphine exhibited inhibitory response during withdrawal, and all the sites that showed inhibitory response to acute morphine exhibited excitatory response during withdrawal. Correlation analysis further quantitatively showed that PGi neurons' responses to acute morphine and that during withdrawal were inversely correlated with a correlation coefficient of 0.73, suggesting that adaptations in the PGi during the development of morphine dependence share common neural mechanisms with the acute effect of morphine. These results provide new insights into the role of the PGi in the development of morphine tolerance/dependence.
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Affiliation(s)
- Hong Zhu
- Department of Otolaryngology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216, USA.
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Haghparast A, Naderi N, Khani A, Lashgari R, Motamedi F. Formalin-Induced Differential Activation of Nucleus Cuneiformis Neurons in the Rat: An Electrophysiological Study. THE JOURNAL OF PAIN 2010; 11:32-43. [DOI: 10.1016/j.jpain.2009.05.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 04/12/2009] [Accepted: 05/22/2009] [Indexed: 11/24/2022]
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Hatami H, Oryan S, Semnanian S, Kazemi B, Bandepour M, Ahmadiani A. Alterations of BDNF and NT-3 genes expression in the nucleus paragigantocellularis during morphine dependency and withdrawal. Neuropeptides 2007; 41:321-8. [PMID: 17688944 DOI: 10.1016/j.npep.2007.04.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 04/27/2007] [Accepted: 04/28/2007] [Indexed: 11/21/2022]
Abstract
Locus coeruleus (LC) plays a key role in opioid dependence and withdrawal. Chronic morphine administration induces neurochemical adaptations in the noradrenergic system. The nature of signal responsible for opiate-induced adaptations of noradrenergic neurons in LC is not well defined. Neurotrophins-signaling pathways such as brain derived neurotrophic factor (BDNF) and Neurotrophin-3 (NT-3) play a key role for regulating the noradrenergic response of LC neurons to opiates. The nucleus paragigantocellularis (PGi) is one of the two major afferents to LC. The present study was designed to evaluate the expression of BDNF and NT-3 in the context of opiate dependence and withdrawal in PGi. Such data are important because they could reveal the role of PGi as an additional source of BDNF and NT-3 in the neurochemical plasticity of LC neurons. Opiate dependence was induced by a progressive intraperitoneal treatment of morphine. In morphine dependent group PGi nucleus was extracted for gene expression assay 6h after the last injection of morphine. In spontaneous withdrawal, rats received the same chronic treatment as morphine group. PGi was extracted for gene expression assay 24, 48 and 72 h after the last injection of morphine. PGi nucleus was assayed for the expression of BDNF and NT-3 using semi-quantitative RT-PCR normalized to beta-actin gene expression. Results showed that chronic administration of morphine significantly increased BDNF and NT-3 gene expression in PGi. In spontaneous withdrawal, BDNF/NT-3 genes expression were high in comparison to control group. It seems that BDNF/NT-3 -signaling pathway originating from PGi is essential for opiate-induced adaptations of the LC neurons.
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Affiliation(s)
- Homeira Hatami
- Department of Biology, Teacher Training University, Tehran, Iran
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20
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Morgan MM, Clayton CC, Boyer-Quick JS. Differential susceptibility of the PAG and RVM to tolerance to the antinociceptive effect of morphine in the rat. Pain 2005; 113:91-8. [PMID: 15621368 DOI: 10.1016/j.pain.2004.09.039] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2004] [Revised: 09/08/2004] [Accepted: 09/28/2004] [Indexed: 11/25/2022]
Abstract
The periaqueductal gray (PAG) and rostral ventromedial medulla (RVM) are part of a nociceptive modulatory system. Microinjection of morphine into either structure produces antinociception. Tolerance develops to ventrolateral PAG mediated antinociception with repeated microinjection of morphine. In contrast, there are no published reports of tolerance to morphine administration into the RVM. Three experiments were conducted to determine whether tolerance develops to morphine microinjections into the RVM. Experiment 1 compared tolerance to the antinociceptive effect of microinjecting morphine (5 microg/0.5 microl) into the PAG and RVM following daily injections for four consecutive days. Experiment 2 assessed tolerance to a range of morphine doses (2.5-20 microg) after injecting morphine into the RVM twice a day for two consecutive days. Experiment 3 followed a similar procedure except twice as many RVM injections were made (8 microinjections in 4 days). The degree to which tolerance developed to the antinociceptive effect of morphine was much greater with microinjections into the PAG compared to the RVM. There was a 64% drop in hot plate latency from the first to the fifth injection of morphine into the PAG, but only a 36% drop in latency following RVM microinjections. Reducing the interdose interval to two injections a day or increasing the total number of injections from 4 to 8 did not enhance the development of tolerance to RVM morphine administration. These data demonstrate that opioid-sensitive neurons in the RVM are relatively resistant to the development of tolerance compared to PAG neurons.
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Affiliation(s)
- Michael M Morgan
- Department of Psychology, Washington State University, 14204 NE Salmon Creek Avenue, Vancouver, WA 98686, USA.
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21
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Bagley EE, Gerke MB, Vaughan CW, Hack SP, Christie MJ. GABA Transporter Currents Activated by Protein Kinase A Excite Midbrain Neurons during Opioid Withdrawal. Neuron 2005; 45:433-45. [PMID: 15694329 DOI: 10.1016/j.neuron.2004.12.049] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2004] [Revised: 12/10/2004] [Accepted: 12/17/2004] [Indexed: 11/20/2022]
Abstract
Adaptations in neurons of the midbrain periaqueductal gray (PAG) induced by chronic morphine treatment mediate expression of many signs of opioid withdrawal. The abnormally elevated action potential rate of opioid-sensitive PAG neurons is a likely cellular mechanism for withdrawal expression. We report here that opioid withdrawal in vitro induced an opioid-sensitive cation current that was mediated by the GABA transporter-1 (GAT-1) and required activation of protein kinase A (PKA) for its expression. Inhibition of GAT-1 or PKA also prevented withdrawal-induced hyperexcitation of PAG neurons. Our findings indicate that GAT-1 currents can directly increase the action potential rates of neurons and that GAT-1 may be a target for therapy to alleviate opioid-withdrawal symptoms.
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Affiliation(s)
- Elena E Bagley
- Pain Management Research Institute at Royal North Shore Hospital, The University of Sydney, NSW 2006, Australia.
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22
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Lane DA, Patel PA, Morgan MM. Evidence for an intrinsic mechanism of antinociceptive tolerance within the ventrolateral periaqueductal gray of rats. Neuroscience 2005; 135:227-34. [PMID: 16084660 DOI: 10.1016/j.neuroscience.2005.06.014] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Revised: 04/22/2005] [Accepted: 06/09/2005] [Indexed: 11/26/2022]
Abstract
Repeated microinjections of morphine into the ventrolateral periaqueductal gray produce antinociceptive tolerance. This tolerance may be a direct effect of morphine on cells within the ventrolateral periaqueductal gray or may require activation of downstream structures such as the rostral ventromedial medulla or spinal cord. Experiment 1 examined whether tolerance develops when opioid receptors in the ventrolateral periaqueductal gray are blocked prior to repeated systemic morphine administration. Microinjections of naltrexone hydrochloride (1microg/0.4microl) into the ventrolateral periaqueductal gray blocked antinociception and significantly attenuated the development of antinociceptive tolerance produced from systemic morphine administration. Experiment 2 examined whether tolerance develops when the effects of morphine are isolated to the ventrolateral periaqueductal gray. This was accomplished by microinjecting morphine (5microg/0.4microl) into the ventrolateral periaqueductal gray while simultaneously blocking the descending output through the rostral ventromedial medulla. Inhibition of neurons within the rostral ventromedial medulla by microinjecting the GABA(A) agonist muscimol (10ng/0.5microl) blocked the antinociception produced by microinjection of morphine into the ventrolateral periaqueductal gray but did not block the development of tolerance. These data demonstrate that the ventrolateral periaqueductal gray is both necessary and sufficient to produce tolerance to the antinociceptive effect of morphine. The ventrolateral periaqueductal gray is necessary in that tolerance does not develop if opiate action within the ventrolateral periaqueductal gray is blocked (experiment 1). The ventrolateral periaqueductal gray is sufficient in that tolerance occurs even when morphine's effects are restricted to the ventrolateral periaqueductal gray (experiment 2).
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Affiliation(s)
- D A Lane
- Washington State University Vancouver, 14204 Northeast Salmon Creek Avenue, Vancouver, WA 98686, USA
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23
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Sinchaisuk S, Ho IK, Rockhold RW. Focal kappa-opioid receptor-mediated dependence and withdrawal in the nucleus paragigantocellularis. Pharmacol Biochem Behav 2002; 74:241-52. [PMID: 12376173 DOI: 10.1016/s0091-3057(02)00993-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The nucleus paragigantocellularis (PGi) has been hypothesized to play an important role in the development of physical dependence on opioids, including the prototype mu-opioid receptor agonist, morphine, and the mixed agonist/antagonist, butorphanol, which shows selective kappa-opioid receptor agonist activity, in rats. In confirmation of previous work, electrical stimulation of the PGi in opioid-nai;ve rats induced stimulus-intensity-related, withdrawal-like behaviors similar to those observed during naloxone-precipitated withdrawal from dependence upon butorphanol. Novel findings were made in rats surgically implanted with cannulae aimed at the lateral ventricle and the right PGi and made physically dependent by intracerebroventricular infusion of either morphine (26 nmol/microl/h) or butorphanol (26 nmol/microl/h) through an osmotic minipump for 3 days. Two hours following termination of the opioid infusion, microinjections of naloxone (11 nmol/400 nl), a nonselective opioid receptor antagonist, or nor-binaltorphimine (nor-BNI) (3.84 nmol/400 nl), a selective kappa-opioid receptor antagonist, were made into the PGi of morphine-dependent and butorphanol-dependent rats. Discrete PGi injections precipitated withdrawal behaviors, with significant (P<.05) increases noted in the incidence of teeth chattering, wet-dog shakes, and scratching. Composite scores for behavioral withdrawal were significantly higher in nor-BNI-precipitated, butorphanol-dependent rats (score=6.8+/-0.6), in naloxone-precipitated, butorphanol-dependent rats (8.9+/-0.8), and in naloxone-precipitated, morphine-dependent rats (11.5+/-0.9) than in all other groups. Both kappa- and mu-opioid receptor mediated dependence can be demonstrated at the level of a discrete medullary site, the PGi, which further supports a specific role for this nucleus in elicitation of behavioral responses during opioid withdrawal.
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Affiliation(s)
- S Sinchaisuk
- Department of Pharmacology and Toxicology, The University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216-4505, USA
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24
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Khalili M, Semnanian S, Fathollahi Y. Caffeine increases paragigantocellularis neuronal firing rate and induces withdrawal signs in morphine-dependent rats. Eur J Pharmacol 2001; 412:239-45. [PMID: 11166287 DOI: 10.1016/s0014-2999(01)00718-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Using single unit recording in nucleus paragigantocellularis neurons located in the rostral ventrolateral medulla, and measuring the precipitated withdrawal syndrome, we investigated whether chronic morphine administration would produce adaptive changes in the adenosine system. Caffeine (50 mg/kg, i.p.) induced withdrawal signs (head shakes, tooth chattering, ejaculation, chewing, and irritability) in morphine-dependent rats 10-18 min after the injection. Only the tooth chattering and diarrhea were expressed following a direct paragigantocellularis injection of caffeine (200 microM, 0.5 microl). The spontaneous activity of paragigantocellularis neurons was significantly decreased by microinjection of both adenosine (10 nM) and an adenosine A1 receptor-selective agonist, cyclohexyladenosine (200 microM), into the paragigantocellularis nucleus of both control and morphine-dependent rats, but the decrease in firing rate of paragigantocellularis neurons of morphine-dependent rats was greater than that of control ones. There was also a significant enhancement of spontaneous activity of paragigantocellularis neurons 8-15 min after caffeine administration (50 mg/kg, i.p.) and 10-18 min after the injection of an adenosine A1 receptor-selective antagonist 8-phenyltheophylline (10 mg/kg, i.p.) in both control and morphine-dependent rats. However, the effect of the antagonists was greater in morphine-dependent rats than in control ones. These data suggest that there is an increase in the sensitivity of nucleus paragigantocellularis neurons to adenosine receptor ligands in morphine-dependent rats that may be associated with the ability of caffeine to produce withdrawal signs.
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Affiliation(s)
- M Khalili
- Department of Physiology, School of Medical Science, Tarbiat Modarres University, PO Box 14115-111, Tehran, Iran.
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25
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Saiepour MH, Semnanian S, Fathollahi Y. Occurrence of morphine tolerance and dependence in the nucleus paragigantocellularis neurons. Eur J Pharmacol 2001; 411:85-92. [PMID: 11137862 DOI: 10.1016/s0014-2999(00)00862-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The occurrence of morphine tolerance and dependence in the nucleus paragigantocellularis neurons was investigated. The spontaneous activity was recorded from the nucleus paragigantocellularis neurons of urethane-anesthetized rats, using single unit recording. Morphine microinjected (20 mg/ml, 120-200 nl) into the nucleus paragigantocellularis of control rats had both excitatory and inhibitory effects. These effects were reversed by microinjection of naloxone, revealing the possible involvement of mu receptors. Morphine microinjected into morphine-dependent rats failed to change the spontaneous activity of the nucleus paragigantocellularis neurons that accounts for the occurrence of tolerance to morphine in these neurons. Microinjection of naloxone (25 mg/ml, 120-200 nl) in control rats had no effect on the spontaneous firing rate of the nucleus paragigantocellularis neurons but in morphine-dependent rats, either alone or after morphine microinjection, naloxone increased neuronal activity significantly, indicating the occurrence of dependence on morphine in the nucleus paragigantocellularis neurons. These data show that the nucleus paragigantocellularis neurons may play a role in physical dependence on morphine. This conclusion is consistent with the finding, that activation of the nucleus paragigantocellularis by electrical stimulation in morphine-naive rats can elicit behaviors similar to those observed during naloxone-precipitated morphine withdrawal.
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Affiliation(s)
- M H Saiepour
- Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran, Iran.
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Williams JT, Christie MJ, Manzoni O. Cellular and synaptic adaptations mediating opioid dependence. Physiol Rev 2001; 81:299-343. [PMID: 11152760 DOI: 10.1152/physrev.2001.81.1.299] [Citation(s) in RCA: 602] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although opioids are highly effective for the treatment of pain, they are also known to be intensely addictive. There has been a massive research investment in the development of opioid analgesics, resulting in a plethora of compounds with varying affinity and efficacy at all the known opioid receptor subtypes. Although compounds of extremely high potency have been produced, the problem of tolerance to and dependence on these agonists persists. This review centers on the adaptive changes in cellular and synaptic function induced by chronic morphine treatment. The initial steps of opioid action are mediated through the activation of G protein-linked receptors. As is true for all G protein-linked receptors, opioid receptors activate and regulate multiple second messenger pathways associated with effector coupling, receptor trafficking, and nuclear signaling. These events are critical for understanding the early events leading to nonassociative tolerance and dependence. Equally important are associative and network changes that affect neurons that do not have opioid receptors but that are indirectly altered by opioid-sensitive cells. Finally, opioids and other drugs of abuse have some common cellular and anatomical pathways. The characterization of common pathways affected by different drugs, particularly after repeated treatment, is important in the understanding of drug abuse.
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Affiliation(s)
- J T Williams
- Vollum Institute, Oregon Health Sciences University, Portland, Oregon, USA.
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27
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Zamani R, Semnanian S, Fathollahi Y, Hajizadeh S. Systemic naloxone enhances cerebral blood flow in anesthetized morphine-dependent rats. Eur J Pharmacol 2000; 408:299-304. [PMID: 11090647 DOI: 10.1016/s0014-2999(00)00794-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Laser-Doppler flowmetry was used to study cerebral cortical blood flow responses to morphine and naloxone in morphine-naive and -dependent rats. The experiments were performed in spontaneously breathing anesthetized rats. Morphine (10 mg/kg, i.p.) administration reduced regional cerebral blood flow in control, sham-operated and morphine-dependent rats, but the depressant effect of morphine in morphine-dependent animals was less than that in control and sham-operated groups. While naloxone (0.5 mg/kg, s.c.) had no considerable effect on regional cerebral blood flow in control and sham-operated groups, it increased regional blood flow in morphine dependent ones. The depressant effect of morphine in all groups and the enhancing effect of naloxone in morphine-dependent animals were not seen after local application of lidocaine at the recording site. This study may provide a framework to study the cellular and molecular mechanisms responsible for coupling neuronal electrical activity with regional alterations in blood flow during precipitation of morphine withdrawal.
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Affiliation(s)
- R Zamani
- Department of Physiology, School of Medical Sciences, Tarbiat Modarres University, P.O. Box 14115-111, Tehran, Iran
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28
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Abstract
This paper is the twenty-first installment of our annual review of research concerning the opiate system. It summarizes papers published during 1998 that studied the behavioral effects of the opiate peptides and antagonists, excluding the purely analgesic effects, although stress-induced analgesia is included. The specific topics covered this year include stress; tolerance and dependence; eating and drinking; alcohol; gastrointestinal, renal, and hepatic function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurologic disorders; electrical-related activity; general activity and locomotion; sex, pregnancy, and development; immunologic responses; and other behaviors.
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Affiliation(s)
- A L Vaccarino
- Department of Psychology, University of New Orleans, LA 70148, USA.
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