ETHANOL WITHDRAWAL DOES NOT INDUCE A REDUCTION IN THE NUMBER OF SPONTANEOUSLY ACTIVE DOPAMINERGIC-NEURONS IN THE MESOLIMBIC SYSTEM

被引:19
作者
DIANA, M [1 ]
PISTIS, M [1 ]
MUNTONI, AL [1 ]
GESSA, GL [1 ]
机构
[1] UNIV CAGLIARI,BB BRODIE DEPT NEUROSCI,I-09124 CAGLIARI,ITALY
关键词
DOPAMINE NEURON; ETHANOL; WITHDRAWAL; DEPOLARIZATION BLOCK; ANESTHESIA;
D O I
10.1016/0006-8993(95)00292-X
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
The effect of ethanol withdrawal, after chronic administration, on the electrophysiological properties of antidromically identified mesoaccumbens dopaminergic neurons was studied in two groups of rats with relative controls (withdrawal from chronic saline). The first group was anesthetized with chloral hydrate whereas the second was immobilized with D-tubocurarine. In chloral hydrate anesthetized rats, a significant reduction in the number of spontaneously active dopamine neurons was observed as compared with chronic saline withdrawn controls. In contrast, in ethanol-withdrawn D-tubocurarine treated rats, the number of spontaneously active dopamine neurons, as measured by the cells/track index, was found not different than chronic saline withdrawn controls. Further, intravenous administration of apomorphine, did not reverse the reduced cells/track index in chloral-hydrate anesthetized rats but consistently inhibited dopaminergic firing. Apomorphine-induced inhibition of firing was significantly more pronounced in ethanol withdrawn chloral-hydrate anesthetized rats. Firing rate and firing pattern were found decreased during ethanol withdrawal irrespective of experimental conditions. The results do not support the possibility that dopaminergic neurons of the mesoaccumbens pathway might be affected by depolarization inactivation during ethanol withdrawal. Rather, they confirm a reduction of neuronal activity already reported by previous studies. The reduced cells/track index observed in chloral hydrate anesthetized rats during ethanol withdrawal awaits an alternative explanation to the depolarization inactivation mechanism.
引用
收藏
页码:29 / 34
页数:6
相关论文
共 23 条
[1]  
Brodie, Shefner, Dunwiddie, Ethanol increases the firing rate of dopamine neurons of the rat ventral tegmenta area in vitro, Brain Res., 508, pp. 65-69, (1990)
[2]  
Bunney, Grace, Acute and chronic haloperidol treatment: comparison of effects on nigral dopaminergic cell activity, Life Sci., 23, pp. 1715-1728, (1978)
[3]  
Carlsson, Magnusson, Svensson, Waldeck, The effect of subhypnotic doses of ethanol on regional catecholamine turnover, Psychopharmacologia, 30, pp. 27-36, (1973)
[4]  
Darden, Hunt, Reduction of striatal dopamine release during an ethanol withdrawal syndrome, J. Neurochem., 29, pp. 1143-1145, (1977)
[5]  
Di Chiara, Imperato, Ethanol preferentially stimulates dopamine release in the nucleus accumbens of freely moving rats, Eur. J. Pharmacol., 115, pp. 131-132, (1985)
[6]  
Di Chiara, Imperato, Drugs abused by humans preferentially increase synaptic dopamine concentration in the mesolimbic system of freely-moving rats, Proc. Natl. Acad. Sci. USA, 85, pp. 5274-5278, (1988)
[7]  
Diana, Pistis, Carboni, Gessa, Rossetti, Profound decrement of mesolimbic dopaminergic neuronal activity during ethanol withdrawal syndrome in rats: electrophysiological and biochemical evidence, Proc. Natl. Acad. Sci. USA, 90, pp. 7966-7969, (1993)
[8]  
Diana, Pistis, Muntoni, Rossetti, Gessa, Marked decrease of A10 dopamine neuronal firing during ethanol withdrawal syndrome in rats, Eur. J. Pharmacol., 221, pp. 403-404, (1992)
[9]  
Eisenhofer, Szabo, Hoffman, Opposite changes in turn-over of noradrenaline and dopamine in the CNS of ethanol-dependent rats, Neuropharmacology, 29, pp. 37-45, (1990)
[10]  
Fadda, Argiolas, Melis, Serra, Gessa, Differential effect of acute and chronic ethanol on dopamine metabolism in frontal cortex, caudate nucleus and substantia nigra, Life Sci., 27, pp. 976-986, (1980)