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Kessi M, Chen B, Pang N, Yang L, Peng J, He F, Yin F. The genotype-phenotype correlations of the CACNA1A-related neurodevelopmental disorders: a small case series and literature reviews. Front Mol Neurosci 2023; 16:1222321. [PMID: 37555011 PMCID: PMC10406136 DOI: 10.3389/fnmol.2023.1222321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Accepted: 07/10/2023] [Indexed: 08/10/2023] Open
Abstract
BACKGROUND Genotype-phenotype correlations of the CACNA1A-related neurodevelopmental disorders such as global developmental delay (GDD)/intellectual disability (ID), epileptic encephalopathy (EE), and autism spectrum disorder (ASD) are unknown. We aimed to summarize genotype-phenotype correlations and potential treatment for CACNA1A-related neurodevelopmental disorders. METHODS Six children diagnosed with CACNA1A-related neurodevelopmental disorders at Xiangya Hospital, Central South University from April 2018 to July 2021 were enrolled. The PubMed database was systematically searched for all reported patients with CACNA1A-related neurodevelopmental disorders until February 2023. Thereafter, we divided patients into several groups for comparison. RESULTS Six patients were recruited from our hospital. Three cases presented with epilepsy, five with GDD/ID, five with ataxia, and two with ASD. The variants included p.G701R, p.R279C, p.D1644N, p.Y62C, p.L1422Sfs*8, and p. R1664Q [two gain-of-function (GOF) and four loss-of-function (LOF) variants]. About 187 individuals with GDD/ID harboring 123 variants were found (case series plus data from literature). Of those 123 variants, p.A713T and p.R1664* were recurrent, 37 were LOF, and 7 were GOF. GOF variants were linked with severe-profound GDD/ID while LOF variants were associated with mild-moderate GDD/ID (p = 0.001). The p.A713T variant correlated with severe-profound GDD/ID (p = 0.003). A total of 130 epileptic patients harboring 83 variants were identified. The epileptic manifestations included status epilepticus (n = 64), provoked seizures (n = 49), focal seizures (n = 37), EE (n = 29), absence seizures (n = 26), and myoclonic seizures (n = 10). About 49 (42.20%) patients had controlled seizures while 67 (57.80%) individuals remained with refractory seizures. Status epilepticus correlated with variants located on S4, S5, and S6 (p = 0.000). Among the 83 epilepsy-related variants, 23 were recurrent, 32 were LOF, and 11 were GOF. Status epilepticus was linked with GOF variants (p = 0.000). LOF variants were associated with absence seizures (p = 0.000). Six patients died at an early age (3 months to ≤5 years). We found 18 children with ASD. Thirteen variants including recurrent ones were identified in those 18 cases. GOF changes were more linked to ASD. CONCLUSION The p.A713T variant is linked with severe-profound GDD/ID. More than half of CACNA1A-related epilepsy is refractory. The most common epileptic manifestation is status epilepticus, which correlates with variants located on S4, S5, and S6.
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Affiliation(s)
- Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Baiyu Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China
- Clinical Research Center for Children’s Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
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McCarthy CI, Mustafá ER, Cornejo MP, Yaneff A, Rodríguez SS, Perello M, Raingo J. Chlorpromazine, an Inverse Agonist of D1R-Like, Differentially Targets Voltage-Gated Calcium Channel (Ca V) Subtypes in mPFC Neurons. Mol Neurobiol 2023; 60:2644-2660. [PMID: 36694048 DOI: 10.1007/s12035-023-03221-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/04/2023] [Indexed: 01/26/2023]
Abstract
The dopamine receptor type 1 (D1R) and the dopamine receptor type 5 (D5R), which are often grouped as D1R-like due to their sequence and signaling similarities, exhibit high levels of constitutive activity. The molecular basis for this agonist-independent activation has been well characterized through biochemical and mutagenesis in vitro studies. In this regard, it was reported that many antipsychotic drugs act as inverse agonists of D1R-like constitutive activity. On the other hand, D1R is highly expressed in the medial prefrontal cortex (mPFC), a brain area with important functions such as working memory. Here, we studied the impact of D1R-like constitutive activity and chlorpromazine (CPZ), an antipsychotic drug and D1R-like inverse agonist, on various neuronal CaV conductances, and we explored its effect on calcium-dependent neuronal functions in the mouse medial mPFC. Using ex vivo brain slices containing the mPFC and transfected HEK293T cells, we found that CPZ reduces CaV2.2 currents by occluding D1R-like constitutive activity, in agreement with a mechanism previously reported by our lab, whereas CPZ directly inhibits CaV1 currents in a D1R-like activity independent manner. In contrast, CPZ and D1R constitutive activity did not affect CaV2.1, CaV2.3, or CaV3 currents. Finally, we found that CPZ reduces excitatory postsynaptic responses in mPFC neurons. Our results contribute to understanding CPZ molecular targets in neurons and describe a novel physiological consequence of CPZ non-canonical action as a D1R-like inverse agonist in the mouse brain.
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Affiliation(s)
- Clara Inés McCarthy
- Electrophysiology Laboratory of the Multidisciplinary Institute of Cell Biology (Argentine Research Council CONICET, Scientific Research Commission of the Buenos Aires Province and National University of La Plata), La Plata, Buenos Aires, Argentina
| | - Emilio Román Mustafá
- Electrophysiology Laboratory of the Multidisciplinary Institute of Cell Biology (Argentine Research Council CONICET, Scientific Research Commission of the Buenos Aires Province and National University of La Plata), La Plata, Buenos Aires, Argentina
| | - María Paula Cornejo
- Neurophysiology Laboratory of the Multidisciplinary Institute of Cell Biology (Argentine Research Council CONICET, Scientific Research Commission of the Buenos Aires Province and National University of La Plata), La Plata, Buenos Aires, Argentina
| | - Agustín Yaneff
- Instituto de Investigaciones Farmacológicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Silvia Susana Rodríguez
- Electrophysiology Laboratory of the Multidisciplinary Institute of Cell Biology (Argentine Research Council CONICET, Scientific Research Commission of the Buenos Aires Province and National University of La Plata), La Plata, Buenos Aires, Argentina
| | - Mario Perello
- Neurophysiology Laboratory of the Multidisciplinary Institute of Cell Biology (Argentine Research Council CONICET, Scientific Research Commission of the Buenos Aires Province and National University of La Plata), La Plata, Buenos Aires, Argentina
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, University of Uppsala, Uppsala, Sweden
| | - Jesica Raingo
- Electrophysiology Laboratory of the Multidisciplinary Institute of Cell Biology (Argentine Research Council CONICET, Scientific Research Commission of the Buenos Aires Province and National University of La Plata), La Plata, Buenos Aires, Argentina.
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Nishijo T, Suzuki E, Momiyama T. Serotonin 5‐HT
1A
and 5‐HT
1B
receptor‐mediated inhibition of glutamatergic transmission onto rat basal forebrain cholinergic neurones. J Physiol 2022; 600:3149-3167. [DOI: 10.1113/jp282509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 05/18/2022] [Indexed: 11/08/2022] Open
Affiliation(s)
- Takuma Nishijo
- Department of Pharmacology Jikei University School of Medicine 3‐25‐8 Nishi‐Shimbashi, Minato‐ku Tokyo 105–8461 Japan
- Department of Molecular Neurobiology Institute for Developmental Research Aichi Developmental Disability Center, 713–8 Kamiya Kasugai Aichi 480‐0392 Japan
| | - Etsuko Suzuki
- Department of Pharmacology Jikei University School of Medicine 3‐25‐8 Nishi‐Shimbashi, Minato‐ku Tokyo 105–8461 Japan
| | - Toshihiko Momiyama
- Department of Pharmacology Jikei University School of Medicine 3‐25‐8 Nishi‐Shimbashi, Minato‐ku Tokyo 105–8461 Japan
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Suzuki E, Momiyama T. M1 muscarinic acetylcholine receptor-mediated inhibition of GABA release from striatal medium spiny neurons onto cholinergic interneurons. Eur J Neurosci 2020; 53:796-813. [PMID: 33270289 DOI: 10.1111/ejn.15074] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/10/2020] [Accepted: 11/24/2020] [Indexed: 11/26/2022]
Abstract
Acetylcholine (ACh) modulates neurotransmitter release in the central nervous system. Although GABAergic transmission onto the striatal cholinergic interneurons (ChIN) is modulated by dopamine receptors, cholinergic modulation of the same synapse is still unknown. In the present study, modulatory roles of ACh in the GABAergic transmission from striatal medium spiny neurons (MSNs) onto ChIN were investigated using optogenetics and whole-cell patch-clamp technique in juvenile and young-adult mice brain slices. GABAA receptor-mediated inhibitory postsynaptic currents (IPSCs) were evoked by focal electrical- or blue-light stimulation. Bath application of carbachol, a muscarinic ACh receptor agonist, suppressed the amplitude of IPSCs in a concentration-dependent manner in both age groups. A choline esterase inhibitor, physostigmine, also suppressed the amplitude of IPSCs. In the presence of a membrane permeable M1 muscarine receptor antagonist, pirenzepine, carbachol-induced suppression of IPSCs was antagonized, whereas a M2 muscarine receptor antagonist, a M4 receptor antagonist, or a membrane impermeable M1 receptor antagonist did not antagonize carbachol-induced suppression of IPSCs. Retrograde cannabinoid cascade via cannabinoid receptor 1 was not involved in carbachol-induced inhibition. Furthermore, carbachol did not affect amplitude of inward currents induced by puff application of GABA, whereas coefficient of variation of IPSCs was significantly increased by carbachol. These results suggest that activation of presynaptic M1 muscarine receptors located on the GABAergic terminals including intracellular organelle of MSNs inhibits GABA release onto ChIN.
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Affiliation(s)
- Etsuko Suzuki
- Department of Pharmacology, Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | - Toshihiko Momiyama
- Department of Pharmacology, Jikei University School of Medicine, Minato-ku, Tokyo, Japan
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Darvish-Ghane S, Quintana C, Beaulieu JM, Martin LJ. D1 receptors in the anterior cingulate cortex modulate basal mechanical sensitivity threshold and glutamatergic synaptic transmission. Mol Brain 2020; 13:121. [PMID: 32891169 PMCID: PMC7487672 DOI: 10.1186/s13041-020-00661-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/26/2020] [Indexed: 02/07/2023] Open
Abstract
The release of dopamine (DA) into target brain areas is considered an essential event for the modulation of many physiological effects. While the anterior cingulate cortex (ACC) has been implicated in pain related behavioral processes, DA modulation of synaptic transmission within the ACC and pain related phenotypes remains unclear. Here we characterized a Crispr/Cas9 mediated somatic knockout of the D1 receptor (D1R) in all neuronal subtypes of the ACC and find reduced mechanical thresholds, without affecting locomotion and anxiety. Further, the D1R high-efficacy agonist SKF 81297 and low efficacy agonist (±)-SKF-38393 inhibit α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptor (AMPAR) currents in the ACC. Paradoxically, the D1R antagonists SCH-23390 and SCH 33961 when co-applied with D1R agonists produced a robust short-term synergistic depression of AMPAR currents in the ACC, demonstrating an overall inhibitory role for D1R ligands. Overall, our data indicate that absence of D1Rs in the ACC enhanced peripheral sensitivity to mechanical stimuli and D1R activation decreased glutamatergic synaptic transmission in ACC neurons.
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Affiliation(s)
- Soroush Darvish-Ghane
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Clémentine Quintana
- Department of Pharmacology and Toxicology, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada
| | - Jean-Martin Beaulieu
- Department of Pharmacology and Toxicology, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada.
| | - Loren J Martin
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON, L5L1C6, Canada.
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Presynaptic Inhibition of Primary Nociceptive Signals to Dorsal Horn Lamina I Neurons by Dopamine. J Neurosci 2018; 38:8809-8821. [PMID: 30143577 DOI: 10.1523/jneurosci.0323-18.2018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 07/18/2018] [Accepted: 08/09/2018] [Indexed: 01/10/2023] Open
Abstract
The dorsal horn of the spinal cord represents the first relay station in the pain pathway where primary nociceptive inputs are modulated by local circuits and by descending signals before being relayed to supraspinal nuclei. To determine whether dopamine can modulate primary nociceptive Aδ- and C-fiber signals, the effects of dopamine were tested on the excitatory postsynaptic currents (EPSCs) recorded from large lamina I neurons and from retrograde-labeled spinoparabrachial lamina I neurons upon stimulation of the L4/L5 dorsal root in horizontal spinal cord slices in vitro Dopamine inhibited the EPSCs in a dose-dependent manner, with substantial inhibition (33%) at 1 μm and maximum inhibition (∼70%) at 10-20 μm Dopamine reduced the frequency of miniature EPSCs recorded from large lamina I neurons, increased the paired pulse depression ratio of paired EPSCs, and induced similar inhibition of EPSCs after dialysis of large lamina I neurons with GDP-β-S, consistent with actions at presynaptic sites. Pharmacological experiments suggested that the inhibitory effects of dopamine were largely mediated by D4 receptors (53%). Similar inhibition (66%) by dopamine was observed on EPSCs recorded from ipsilateral large lamina I neurons 6 d after injection of complete Freund's adjuvant in the hindpaw, suggesting that dopamine downregulates primary nociceptive inputs to lamina I neurons during chronic inflammatory pain. We propose that presynaptic inhibition of primary nociceptive inputs to lamina I projection neurons is a mechanism whereby dopamine can inhibit incoming noxious stimuli to the dorsal horn of the spinal cord.SIGNIFICANCE STATEMENT Lamina I projection neurons represent the main output for the pain signals from the dorsal horn of the spinal cord to brainstem and thalamic nuclei. We found that dopamine inhibits the nociceptive Aδ- and C-fiber synaptic inputs to lamina I projection neurons via presynaptic actions. Similar inhibitory effects of dopamine on the EPSCs were observed in rats subjected to complete Freund's adjuvant to induce peripheral inflammation, suggesting that dopamine inhibits the synaptic inputs to lamina I neurons in the setting of injury. A better understanding of how primary nociceptive inputs to the dorsal horn of the spinal cord are modulated by descending monoaminergic signals may help in the development of new pharmacological strategies to selectively downregulate the output from lamina I projection neurons.
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7
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Momiyama T, Nishijo T. Dopamine and Serotonin-Induced Modulation of GABAergic and Glutamatergic Transmission in the Striatum and Basal Forebrain. Front Neuroanat 2017; 11:42. [PMID: 28553205 PMCID: PMC5425578 DOI: 10.3389/fnana.2017.00042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 04/28/2017] [Indexed: 12/12/2022] Open
Abstract
Catecholamine receptor-mediated modulation of glutamatergic or GABAergic transmission in the striatum as well as basal forebrain (BF) has been intensively studied during these two decades. In the striatum, activation of dopamine (DA) D2 receptors in GABAergic terminals inhibits GABA release onto cholinergic interneurons by selective blockade of N-type calcium channels. In the BF, glutamatergic transmission onto cholinergic projection neurons is inhibited via DA D1-like receptors by selective blockade of P/Q-type calcium channels. On the other hand, presynaptic inhibition of the GABA release onto cholinergic neurons mediated by D1-like receptors or 5-HT1B receptors is independent of calcium influx. In addition, the DA receptor-mediated calcium influx dependent presynaptic inhibition mentioned above decreases with postnatal development, with selective coupling between DA receptors and each subtype of calcium channels being unchanged. Furthermore, the precise origin of these GABAergic or glutamatergic inputs to postsynaptic neurons can be identified by recent optogenetic approaches. Thus, modulatory mechanisms in specific synaptic connections between certain types of neurons in the striatum and BF are being identified.
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Affiliation(s)
- Toshihiko Momiyama
- Department of Pharmacology, Jikei University School of MedicineTokyo, Japan
| | - Takuma Nishijo
- Department of Pharmacology, Jikei University School of MedicineTokyo, Japan
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8
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Nishijo T, Momiyama T. Serotonin 5-HT1Breceptor-mediated calcium influx-independent presynaptic inhibition of GABA release onto rat basal forebrain cholinergic neurons. Eur J Neurosci 2016; 44:1747-60. [DOI: 10.1111/ejn.13273] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/06/2016] [Accepted: 04/11/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Takuma Nishijo
- Department of Pharmacology; Jikei University School of Medicine; Nishi-Shimbashi, Minato-ku Tokyo 105-8461 Japan
| | - Toshihiko Momiyama
- Department of Pharmacology; Jikei University School of Medicine; Nishi-Shimbashi, Minato-ku Tokyo 105-8461 Japan
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de Kloet SF, Mansvelder HD, De Vries TJ. Cholinergic modulation of dopamine pathways through nicotinic acetylcholine receptors. Biochem Pharmacol 2015. [PMID: 26208783 DOI: 10.1016/j.bcp.2015.07.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Nicotine addiction is highly prevalent in current society and is often comorbid with other diseases. In the central nervous system, nicotine acts as an agonist for nicotinic acetylcholine receptors (nAChRs) and its effects depend on location and receptor composition. Although nicotinic receptors are found in most brain regions, many studies on addiction have focused on the mesolimbic system and its reported behavioral correlates such as reward processing and reinforcement learning. Profound modulatory cholinergic input from the pedunculopontine and laterodorsal tegmentum to dopaminergic midbrain nuclei as well as local cholinergic interneuron projections to dopamine neuron axons in the striatum may play a major role in the effects of nicotine. Moreover, an indirect mesocorticolimbic feedback loop involving the medial prefrontal cortex may be involved in behavioral characteristics of nicotine addiction. Therefore, this review will highlight current understanding of the effects of nicotine on the function of mesolimbic and mesocortical dopamine projections in the mesocorticolimbic circuit.
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Affiliation(s)
- Sybren F de Kloet
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cogntive Research (CNCR), Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cogntive Research (CNCR), Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands.
| | - Taco J De Vries
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cogntive Research (CNCR), Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands; Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
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10
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Stürmer GD, de Freitas TC, Heberle MDA, de Assis DR, Vinadé L, Pereira AB, Franco JL, Dal Belo CA. Modulation of dopaminergic neurotransmission induced by sublethal doses of the organophosphate trichlorfon in cockroaches. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 109:56-62. [PMID: 25164203 DOI: 10.1016/j.ecoenv.2014.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 08/03/2014] [Accepted: 08/05/2014] [Indexed: 06/03/2023]
Abstract
Organophosphate (OP) insecticides have been used indiscriminately, based on their high dissipation rates and low residual levels in the environment. Despite the toxicity of OPs to beneficial insects is principally devoted to the acetylcholinesterase (AChE) inhibition, the physiological mechanisms underlying this activity remain poorly understood. Here we showed the pharmacological pathways that might be involved in severe alterations in the insect locomotion and grooming behaviors following sublethal administration of the OP Trichlorfon (Tn) (0.25, 0.5 and 1 µM) in Phoetalia pallida. Tn inhibited the acetylcholinesterase activity (46±6, 38±3 and 24±6 nmol NADPH/min/mg protein, n=3, p<0.05), respectively. Tn (1 µM) also increased the walking maintenance of animals (46±5 s; n=27; p<0.05). Tn caused a high increase in the time spent for this behavior (344±18 s/30 min, 388±18 s/30 min and 228±12 s/30 min, n=29-30, p<0.05, respectively). The previous treatment of the animals with different cholinergic modulators showed that pirenzepine>atropine>oxotremorine>d-tubocurarine>tropicamide>methoctramine induced a decrease on Tn (0.5 µM)-induced grooming increase, respectively in order of potency. Metoclopramide (0.4 µM), a DA-D2 selective inhibitor decreased the Tn-induced grooming activity (158±12 s/30 min; n=29; p<0.05). Nevertheless, the effect of the selective DA-D1 receptor blocker SCH 23390 (1.85 µM) on the Tn (0.5 µM)-induced grooming increase was significative and more intense than that of metoclopramide (54±6 s/30 min; n=30; p<0.05). Taken together the results suggest that a cross-talking between cholinergic M1/M3 and dopaminergic D1 receptors at the insect nervous system may play a role in the OP-mediated behavioral alterations.
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Affiliation(s)
- Graziele Daiane Stürmer
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil
| | - Thiago Carrazoni de Freitas
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil
| | - Marines de Avila Heberle
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil
| | - Dênis Reis de Assis
- Instituto do Cérebro do Rio Grande do Sul, Pontifícia Universidade, Católica do Rio Grande do Sul, PUCRS, Porto Alegre, RS, Brasil
| | - Lúcia Vinadé
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil
| | - Antônio Batista Pereira
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil
| | - Jeferson Luis Franco
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil
| | - Cháriston André Dal Belo
- CIPBiotec, Universidade Federal do Pampa, (UNIPAMPA), Campus São Gabriel, Av. Antônio Trilha, 1847, Centro, CEP 97300-000, São Gabriel, Rio Grande do Sul, Brasil.
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Anisuzzaman ASM, Uwada J, Masuoka T, Yoshiki H, Nishio M, Ikegaya Y, Takahashi N, Matsuki N, Fujibayashi Y, Yonekura Y, Momiyama T, Muramatsu I. Novel contribution of cell surface and intracellular M1-muscarinic acetylcholine receptors to synaptic plasticity in hippocampus. J Neurochem 2013; 126:360-71. [DOI: 10.1111/jnc.12306] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/30/2013] [Accepted: 05/14/2013] [Indexed: 01/08/2023]
Affiliation(s)
- Abu Syed Md Anisuzzaman
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
| | - Junsuke Uwada
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
- Organization for Life Science Advancement Programs; University of Fukui; Eiheiji Japan
| | - Takayoshi Masuoka
- Department of Pharmacology; School of Medicine; Kanazawa Medical University; Uchinada Japan
| | - Hatsumi Yoshiki
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
| | - Matomo Nishio
- Department of Pharmacology; School of Medicine; Kanazawa Medical University; Uchinada Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences; The University of Tokyo; Hongo Bunkyo-ku Japan
| | - Naoya Takahashi
- Laboratory of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences; The University of Tokyo; Hongo Bunkyo-ku Japan
| | - Norio Matsuki
- Laboratory of Chemical Pharmacology; Graduate School of Pharmaceutical Sciences; The University of Tokyo; Hongo Bunkyo-ku Japan
| | | | | | - Toshihiko Momiyama
- Department of Pharmacology; Jikei University School of Medicine; Minato-ku Japan
| | - Ikunobu Muramatsu
- Division of Pharmacology; Department of Biochemistry and Bioinformative Sciences; School of Medicine; University of Fukui; Eiheiji Japan
- Organization for Life Science Advancement Programs; University of Fukui; Eiheiji Japan
- Child Development Research Center; Graduate School of Medicine; University of Fukui; Eiheiji Japan
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12
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Mahapatra S, Marcantoni A, Zuccotti A, Carabelli V, Carbone E. Equal sensitivity of Cav1.2 and Cav1.3 channels to the opposing modulations of PKA and PKG in mouse chromaffin cells. J Physiol 2012; 590:5053-73. [PMID: 22826131 DOI: 10.1113/jphysiol.2012.236729] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mouse chromaffin cells (MCCs) express high densities of L-type Ca2+ channels (LTCCs), which control pacemaking activity and catecholamine secretion proportionally to their density of expression. In vivo phosphorylation of LTCCs by cAMP-PKA and cGMP–PKG, regulate LTCC gating in two opposing ways: the cAMP-PKA pathway potentiates while the cGMP–PKG cascade inhibits LTCCs. Despite this, no attempts have been made to answer three key questions related to the two Cav1 isoforms expressed in MCCs (Cav1.2 and Cav1.3): (i) how much are the two Cav1 channels basally modulated by PKA and PKG?, (ii) to what extent can Cav1.2 and Cav1.3 be further regulated by PKA or PKG activation?, and (iii) are the effects of both kinases cumulative when simultaneously active? Here, by comparing the size of L-type currents of wild-type (WT; Cav1.2+Cav1.3) and Cav1.3−/− KO (Cav1.2) MCCs, we provide new evidence that both PKA and PKG pathways affect Cav1.2 and Cav1.3 to the same extent either under basal conditions or induced stimulation. Inhibition of PKA by H89 (5 μM) reduced the L-type current in WT and KO MCCs by∼60%,while inhibition of PKG by KT 5823 (1 μM) increased by∼40% the same current in both cell types. Given that Cav1.2 and Cav1.3 carry the same quantity of Ca2+ currents, this suggests equal sensitivity of Cav1.2 and Cav1.3 to the two basal modulatory pathways. Maximal stimulation of cAMP–PKA by forskolin (100 μM) and activation of cGMP–PKG by pCPT-cGMP (1mM) uncovered a∼25% increase of L-type currents in the first case and∼65% inhibition in the second case in both WT and KO MCCs, suggesting equal sensitivity of Cav1.2 and Cav1.3 during maximal PKA or PKG stimulation. The effects of PKA and PKG were cumulative and most evident when one pathway was activated and the other was inhibited. The two extreme combinations(PKA activation–PKG inhibition vs. PKG activation-PKA inhibition) varied the size of L-type currents by one order of magnitude (from 180% to 18% of control size). Taken together our data suggest that: (i) Cav1.2 and Cav1.3 are equally sensitive to PKA and PKG action under both basal conditions and maximal stimulation, and (ii) PKA and PKG act independently on both Cav1.2 and Cav1.3, producing cumulative effects when opposingly activated. These extreme Cav1 channel modulations may occur either during high-frequency sympathetic stimulation to sustain prolonged catecholamine release (maximal L-type current) or following activation of the NO–cGMP–PKG signalling pathway (minimal L-type current) to limit the steady release of catecholamines.
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Hawryluk JM, Ferrari LL, Keating SA, Arrigoni E. Adenosine inhibits glutamatergic input to basal forebrain cholinergic neurons. J Neurophysiol 2012; 107:2769-81. [PMID: 22357797 PMCID: PMC3362278 DOI: 10.1152/jn.00528.2011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 02/15/2012] [Indexed: 01/03/2023] Open
Abstract
Adenosine has been proposed as an endogenous homeostatic sleep factor that accumulates during waking and inhibits wake-active neurons to promote sleep. It has been specifically hypothesized that adenosine decreases wakefulness and promotes sleep recovery by directly inhibiting wake-active neurons of the basal forebrain (BF), particularly BF cholinergic neurons. We previously showed that adenosine directly inhibits BF cholinergic neurons. Here, we investigated 1) how adenosine modulates glutamatergic input to BF cholinergic neurons and 2) how adenosine uptake and adenosine metabolism are involved in regulating extracellular levels of adenosine. Our experiments were conducted using whole cell patch-clamp recordings in mouse brain slices. We found that in BF cholinergic neurons, adenosine reduced the amplitude of AMPA-mediated evoked glutamatergic excitatory postsynaptic currents (EPSCs) and decreased the frequency of spontaneous and miniature EPSCs through presynaptic A(1) receptors. Thus we have demonstrated that in addition to directly inhibiting BF cholinergic neurons, adenosine depresses excitatory inputs to these neurons. It is therefore possible that both direct and indirect inhibition may synergistically contribute to the sleep-promoting effects of adenosine in the BF. We also found that blocking the influx of adenosine through the equilibrative nucleoside transporters or inhibiting adenosine kinase and adenosine deaminase increased endogenous adenosine inhibitory tone, suggesting a possible mechanism through which adenosine extracellular levels in the basal forebrain are regulated.
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Affiliation(s)
- J M Hawryluk
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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Zhang Z, Pan ZZ. Signaling cascades for δ-opioid receptor-mediated inhibition of GABA synaptic transmission and behavioral antinociception. Mol Pharmacol 2011; 81:375-83. [PMID: 22144670 DOI: 10.1124/mol.111.076307] [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
Membrane trafficking of the δ-opioid receptor (DOR) from intracellular compartments to plasma membrane in central neurons, induced by various pathological conditions such as long-term opioid exposure, represents unique receptor plasticity involved in the mechanisms of long-term opioid effects in opioid addiction and opioid treatment of chronic pain. However, the signaling pathways coupled to the newly emerged functional DOR in central neurons are largely unknown at present. In this study, we investigated the signaling cascades of long-term morphine-induced DOR for its cellular and behavioral effects in neurons of the rat brainstem nucleus raphe magnus (NRM), a key supraspinal site for opioid analgesia. We found that, among the three phospholipase A(2) (PLA(2))-regulated arachidonic acid (AA) metabolic pathways of lipoxygenase, cyclooxygenase, and epoxygenase, 12-lipoxygenase of the lipoxygenase pathway primarily mediated DOR inhibition of GABA synaptic transmission, because inhibitors of 12-lipoxygenase as well as lipoxygenases and PLA(2) largely blocked the DOR- or AA-induced GABA inhibition in NRM neurons in brainstem slices in vitro. Blockade of the epoxygenase pathway was ineffective, whereas blocking either 5-lipoxygenase of the lipoxygenase pathway or the cyclooxygenase pathway enhanced the DOR-mediated GABA inhibition. Behaviorally in rats in vivo, NRM infusion of 12-lipoxygenase inhibitors significantly reduced DOR-induced antinociceptive effect whereas inhibitors of 5-lipoxygenase and cyclooxygenase augmented the DOR antinociception. These findings suggest the PLA(2)-AA-12-lipoxygenase pathway as a primary signaling cascade for DOR-mediated analgesia through inhibition of GABA neurotransmission and indicate potential therapeutic benefits of combining 5-lipoxygenase and cyclooxygenase inhibitors for maximal pain inhibition.
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Affiliation(s)
- Zhi Zhang
- Department of Anesthesiology and Pain Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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15
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Momiyama T. Developmental increase in D1-like dopamine receptor-mediated inhibition of glutamatergic transmission through P/Q-type channel regulation in the basal forebrain of rats. Eur J Neurosci 2010; 32:579-90. [PMID: 20718855 DOI: 10.1111/j.1460-9568.2010.07306.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Whole-cell patch-clamp recordings of non-N-methyl-d-aspartate glutamatergic excitatory postsynaptic currents (EPSCs) were carried out from cholinergic neurons in slices of basal forebrain (BF) of developing rats aged 21-42 postnatal days to elucidate postnatal developmental change in Ca(2+) channel subtypes involved in the transmission as well as that in dopamine D(1)-like receptor-mediated presynaptic inhibition. The amplitude of EPSCs was inhibited by bath application of omega-conotoxin GVIA (omega-CgTX; 3 microM) or omega-agatoxin-TK (omega-Aga-TK; 200 nM) throughout the age range examined, suggesting that multiple types of Ca(2+) channel are involved in the transmission. The EPSC fraction reduced by omega-CgTX decreased with age, whereas that reduced by omega-Aga-TK increased. Inhibition of the EPSCs by a D(1)-like receptor agonist, SKF 81297 (SKF; 30 microM) increased with age in parallel with the increase in omega-Aga-TK-induced inhibition. An activator of the adenylyl cyclase (AC) pathway, forskolin (FK; 10 microM) inhibited the EPSCs, and FK-induced inhibition also increased with age in parallel with the increase in SKF-induced inhibition. Throughout the age range examined, SKF showed no further inhibitory effect on the EPSCs after omega-Aga-TK- or FK-induced effect had reached steady-state. These findings suggest that D(1)-like receptor-mediated presynaptic inhibition of glutamate release onto cholinergic BF neurons increases with age, and that the change is coupled with a developmental increase in the contribution of P/Q-type Ca(2+) channels as well as a developmental increase in AC pathway contribution.
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Affiliation(s)
- Toshihiko Momiyama
- Division of Cerebral Structure, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.
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Undieh AS. Pharmacology of signaling induced by dopamine D(1)-like receptor activation. Pharmacol Ther 2010; 128:37-60. [PMID: 20547182 DOI: 10.1016/j.pharmthera.2010.05.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Accepted: 05/19/2010] [Indexed: 12/30/2022]
Abstract
Dopamine D(1)-like receptors consisting of D(1) and D(5) subtypes are intimately implicated in dopaminergic regulation of fundamental neurophysiologic processes such as mood, motivation, cognitive function, and motor activity. Upon stimulation, D(1)-like receptors initiate signal transduction cascades that are mediated through adenylyl cyclase or phosphoinositide metabolism, with subsequent enhancement of multiple downstream kinase cascades. The latter actions propagate and further amplify the receptor signals, thus predisposing D(1)-like receptors to multifaceted interactions with various other mediators and receptor systems. The adenylyl cyclase response to dopamine or selective D(1)-like receptor agonists is reliably associated with the D(1) subtype, while emerging evidence indicates that the phosphoinositide responses in native brain tissues may be preferentially mediated through stimulation of the D(5) receptor. Besides classic coupling of each receptor subtype to specific G proteins, additional biophysical models are advanced in attempts to account for differential subcellular distribution, heteromolecular oligomerization, and activity-dependent selectivity of the receptors. It is expected that significant advances in understanding of dopamine neurobiology will emerge from current and anticipated studies directed at uncovering the molecular mechanisms of D(5) coupling to phosphoinositide signaling, the structural features that might enhance pharmacological selectivity for D(5) versus D(1) subtypes, the mechanism by which dopamine may modulate phosphoinositide synthesis, the contributions of the various responsive signal mediators to D(1) or D(5) interactions with D(2)-like receptors, and the spectrum of dopaminergic functions that may be attributed to each receptor subtype and signaling pathway.
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Affiliation(s)
- Ashiwel S Undieh
- Laboratory of Integrative Neuropharmacology, Department of Pharmaceutical Sciences, Thomas Jefferson University School of Pharmacy, 130 South 9th Street, Suite 1510, Philadelphia, PA 19107, USA.
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D1-like dopamine receptor activation modulates GABAergic inhibition but not electrical coupling between neocortical fast-spiking interneurons. J Neurosci 2008; 28:2633-41. [PMID: 18322106 DOI: 10.1523/jneurosci.5079-07.2008] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Dopamine, acting through D(1) receptors, is thought to play an important role in cognitive functions of the frontal cortex such as working memory. D(1) receptors are widely expressed in fast-spiking (FS) interneurons, a prominent class of inhibitory cells that exert a powerful control of neuronal firing through proximal synapses on their postsynaptic targets. FS cells are extensively mutually interconnected by both GABA(A) receptor-mediated synapses and gap junction-mediated electrical synapses, and networks of FS cells play a crucial role in the generation of rhythmic synchronous activity. Although recent studies have documented the effects of dopamine modulation of neocortical synaptic connections among excitatory cells and between excitatory and various inhibitory cells, the effects of dopamine receptor activation on GABAergic and electrical interactions among FS cells is not known. To resolve this, we recorded from pairs of FS cells in the infragranular layers of mouse neocortical slices and tested the effects of D(1)-like (D(1)/D(5)) receptor activation on these connections. We found that D(1)-like receptor activation modulated GABAergic but not electrical connections between them. A D(1)-like receptor agonist preserved the strength of electrical coupling but reduced the amplitude of IPSPs and IPSCs between FS cells. Our results suggest that D(1)-like receptor activation has synapse-specific effects within networks of FS cells, with potential implications for the generation of rhythmic activity in the neocortex.
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Amyloid beta oligomers (A beta(1-42) globulomer) suppress spontaneous synaptic activity by inhibition of P/Q-type calcium currents. J Neurosci 2008; 28:788-97. [PMID: 18216187 DOI: 10.1523/jneurosci.4771-07.2008] [Citation(s) in RCA: 181] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abnormal accumulation of soluble oligomers of amyloid beta (Abeta) is believed to cause malfunctioning of neurons in Alzheimer's disease. It has been shown that Abeta oligomers impair synaptic plasticity, thereby altering the ability of the neuron to store information. We examined the underlying cellular mechanism of Abeta oligomer-induced synaptic modifications by using a recently described stable oligomeric Abeta preparation called "Abeta(1-42) globulomer." Synthetically prepared Abeta(1-42) globulomer has been shown to localize to neurons and impairs long-term potentiation (Barghorn et al., 2005). Here, we demonstrate that Abeta(1-42) globulomer does not affect intrinsic neuronal properties, as assessed by measuring input resistance and discharge characteristics, excluding an unspecific alteration of membrane properties. We provide evidence that Abeta(1-42) globulomer, at concentrations as low as 8 nM, specifically suppresses spontaneous synaptic activity resulting from a reduction of vesicular release at terminals of both GABAergic and glutamatergic synapses. EPSCs and IPSCs were primarily unaffected. A detailed search for the precise molecular target of Abeta(1-42) globulomer revealed a specific inhibition of presynaptic P/Q calcium currents, whereas other voltage-activated calcium currents remained unaltered. Because intact P/Q calcium currents are needed for synaptic plasticity, the disruption of such currents by Abeta(1-42) globulomer may cause deficits in cellular mechanisms of information storage in brains of Alzheimer's disease patients. The inhibitory effect of Abeta(1-42) globulomer on synaptic vesicle release could be reversed by roscovitine, a specific enhancer of P/Q currents. Selective enhancement of the P/Q calcium current may provide a promising strategy in the treatment of Alzheimer's disease.
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Chin JH, Ma L, MacTavish D, Jhamandas JH. Amyloid beta protein modulates glutamate-mediated neurotransmission in the rat basal forebrain: involvement of presynaptic neuronal nicotinic acetylcholine and metabotropic glutamate receptors. J Neurosci 2007; 27:9262-9. [PMID: 17728440 PMCID: PMC6673123 DOI: 10.1523/jneurosci.1843-07.2007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Amyloid beta (Abeta) protein, a 39-43 amino acid peptide deposited in brains of individuals with Alzheimer's disease (AD), has been shown to interact directly with a number of receptor targets including neuronal nicotinic acetylcholine receptors (nAChRs) and glutamate receptors. In this study, we investigated the synaptic effects of Abeta(1-42) on glutamate-mediated neurotransmission in the diagonal band of Broca (DBB), a cholinergic basal forebrain nucleus. Glutamatergic miniature EPSCs (mEPSCs) were recorded using whole-cell patch-clamp recordings from identified cholinergic DBB neurons in rat forebrain slices. In 54% of DBB neurons, bath application of Abeta(1-42) (100 nM), but not Abeta(42-1) (inverse fragment), significantly increased the frequency of mEPSCs without affecting amplitude or kinetic parameters (rise or decay time). In 32% of DBB neurons, bath application of Abeta(1-42) significantly decreased only the frequency but not amplitude of mEPSCs. Application of dihydro-beta-erythroidine (DHbetaE) (an antagonist for the alpha4beta2 subtype of nAChRs) but not alpha-bungarotoxin (an antagonist for the alpha7 subtype of nAChRs) blocked Abeta(1-42)-mediated increases in mEPSC frequency. The Abeta(1-42)-mediated increase in glutamatergic transmission is thus presynaptic and mediated via non-alpha7 AChRs. In contrast, Abeta(1-42)-mediated decreases in mEPSC frequency could not be antagonized by either DHbetaE or alpha-bungarotoxin. However, the Abeta(1-42)-evoked depression in mEPSC frequency was antagonized by (RS)-alpha-methyl-4-carboxyphenyglycine, a nonselective group I/II metabotropic glutamate receptor antagonist. These observations provide further insight into the mechanisms whereby Abeta affects synaptic function in the brain and may be relevant in the context of synaptic failure observed in AD.
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Affiliation(s)
- James H. Chin
- Department of Medicine (Neurology) and Center for Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2S2
| | - Li Ma
- Department of Medicine (Neurology) and Center for Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2S2
| | - David MacTavish
- Department of Medicine (Neurology) and Center for Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2S2
| | - Jack H. Jhamandas
- Department of Medicine (Neurology) and Center for Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2S2
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