Assessment of Expression of Genes Coding GABAA Receptors during Chronic and Acute Intoxication of Laboratory Rats with Ethanol

Abstract

Expression of genes encoding the individual subunits of ionotropic GABAA receptor was assessed after acute and chronic intoxication of rats with ethanol. The chronic 1-month-long exposure to ethanol signifi cantly decreased (by 38%) expression of Gabrb1 gene in the hippocampus. Acute exposure to ethanol elevated expression of genes Gabrb1 (by 1.7 times), Gabra1 (by 3.8 times), and Gabra4 (by 6.5 times), although it diminished expression of Gabra2 gene by 1.4 times. In preliminarily alcoholized rats, acute intoxication with ethanol enhanced expression of genes Gabrb1 and Gabra5 by 1.7 and 8.7 times, respectively. There was neither acute nor chronic effect of ethanol on expression of gene Gabra3.

Sex Differences in the Expression of the α5 Subunit of the GABAA Receptor in Alcoholics with and without Cirrhosis of the Liver

“…Specifically, a reduction in the expression of GABA A α5 has been noted in schizophrenia and autism and may be correlated with cognitive deficits in those patients (Bristow et al, ). Selected changes in the expression of this subunit of the GABA A receptor have been noted in the brains of human alcoholics (Jin et al, ) as well as in animal models of alcohol misuse (Osechkina et al, ). Further, GABA A α5 receptors are suggested to play a role in mediating some of the behavioral effects of alcohol such as reinforcement and reward (Ruedi‐Bettschen et al, ; Stephens et al, ).…”

“…In laboratory rodents, the expression of GABA A α5 mRNA was decreased in the frontal cortex after 2 weeks and increased in the hippocampus after 12 weeks of EtOH administration (Charlton et al, ). Acute intoxication of alcoholized rats enhanced the expression of GABA A α5 mRNA in the hippocampus (Osechkina et al, ). In humans, the only previously published study measured the expression of GABA A α5 mRNA in the hippocampus, orbitofrontal cortex, and prefrontal cortex of alcohol‐dependent, male alcoholics without cirrhosis of the liver (Jin et al, ).…”

“…Further, alcohol exposure alters the expression of the α1 and α5 subunits in a region‐ and time‐dependent manner (Charlton et al, ). Acute exposure to EtOH of rats that had previously been chronically exposed to alcohol for more than a month resulted in an increase (8.7‐fold) in the expression of the α5 subunit (Osechkina et al, ).…”