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Chronic ethanol exposure increases 3H-GABA release in rat hippocampus by presynaptic muscarinic receptor modulation

, : Chronic ethanol exposure increases 3H-GABA release in rat hippocampus by presynaptic muscarinic receptor modulation. Alcoholism Clinical & Experimental Research 23(10): 1587-1595, Oct

Background: Chronic ethanol treatment (CET) for 28 weeks significantly increases electrically-stimulated 3H-GABA release from hippocampal slices. This increase in GABA release may be one of the mechanisms by which CET decreases the magnitude of long-term potentiation (LTP) in the hippocampus. The present study examined whether CET increases GABA release via an alteration in heterologous presynaptic cholinergic regulation. Methods: Animals were treated with ethanol or sucrose diet for 28 weeks followed by either no withdrawal or a 48-hr withdrawal period. The electrically-stimulated 3H-GABA release from preloaded superfused hippocampal slices of naive and CET rats was measured. Results: Carbachol increased 3H-GABA release in a concentration-dependent manner, and atropine modulated 3H-GABA release in a biphasic concentration-dependent manner. Atropine (10 muM) significantly blocked the effects of carbachol. Oxotremorine, a selective muscarinic receptor agonist, also increased 3H-GAB A release. Mecamylamine, a selective nicotinic antagonist, did not modulate 3H-GABA release and did not block the effects of carbachol. The effects of these agents were also tested in rats 0 or 48 hrs after withdrawal from CET. The biphasic effects of atropine were decreased, whereas the facilitating effects of carbachol were significantly increased. There were no changes in the effects of these agents on 3H-acetylcholine release from hippocampal slices of CET rats compared to sucrose-treated rats. Conclusion: These results suggest that presynaptic muscarinic receptors facilitate GABA release, whereas nicotinic receptors do not play a significant role in modulating GABA release in hippocampus. CET selectively alters presynaptic muscarinic regulation of GABA release in hippocampus and may help us to further understand the mechanism underlying the disruption of LTP by CET.


PMID: 10549989

DOI: 10.1111/j.1530-0277.1999.tb04048.x

Other references

Singh D.; Gulyani R.; Bhasin V., 1992: Cysticercus pisiformis in commercial rabbits. Indian Veterinary Medical Journal 16(1): 71

Myers, J.G., 1929: Observations on the biology of two remarkable Cixiid plant-hoppers (Homoptera) from Cuba. Psyche Boston, 36: 283-292

Wang Duojiang. et al., 1986: A study of three-dimensional reconstruction of brain structure of the tree shrew Tupaia belongeri chinensis 1 Picture of the brain segments by computer aided graphics. Zoological Research, 73: 217-222

Matschke G.H., 1975: Oral acceptance and anti fertility effects of micro encapsulated di ethyl stilbestrol on white tailed does. Proceedings of the Annual Conference Southeastern Association of Game & Fish Commissioners 29: (1976)

Pasero J.; Thibaut J.; Galanakis A., 1973: Production of a lipase by candida lipolytica. Suomalainen, Heikki And Christine Waller (Ed ) Proceedings Of The Third International Specialized Symposium on Yeasts Metabolism And Regulation Of Cellular Processes, Part 1 Abstracts Otaniemi Helsinki, Finland, June 4-8, 159p Symposium Secretariate: Helsinki, Finland 129

Yasunami, M., 1988: Structural analysis of human major histocompatibility complex class II genes. Human MHC class II antigens, which play a crucial role in self-non self recognition and regulate immune responsiveness to foreign antigens, are encoded for by a multigene family in HLA-D region. They show an extreme polymorphism and are in a stron...

Yepez Gil, GA.; Montagne A., A., 1990: Altura de vuelo de coquitos perforadores Andrector arcuatus Olivier y A ruficornis Olivier Coleoptera Chrysomelidae en un campo de caraota Phaseolus vulgaris L. Agronomia Tropical (Maracay): 404-6: 235-244

Novak, S.; Nemeth, W.C., 2008: RE: cost-effectiveness of diagnostic medial branch blocks before radiofrequency denervation. Spine Journal 8(2): 412-413

Capati D.G.; Brewer G.J.; Mathews K.P., 1980: Controlled study of zinc acetate therapy for ragweed hay fever. Clinical Research 28(2): 342A

Brugnara, C.; Kruskall, M.S.; Johnstone, R.M., 1993: Membrane properties of erythrocytes in subjects undergoing multiple blood donations with or without recombinant erythropoietin. To examine the characteristics of young human red cells, we studied blood from seven healthy male volunteers who developed systemic reticulocytosis during a 3-week blood donation period. Each of these subjects donated a total of 6 units (450 ml/un...