MODULATION OF SEROTONIN(2A 2C) RECEPTORS AND THESE RECEPTOR-LINKED PHOSPHOINOSITIDE SYSTEM BY ETHANOL/

Studies related to 5-HT2A/2C receptors and these receptor-linked phosp hoinositide (PI) system in the rat brain during chronic ethanol treatm ent and withdrawal are discussed. Chronic ethanol treatment (60 days) has no effect on 5-HT2A/2C receptors in the cortex and the hippocampus but significantly decreased 5-HT-stimulated PI hydrolysis in the rat cortex. On the other hand, chronic ethanol treatment (60 days) signifi cantly increased 5-HT2A receptors and 5-HT-stimulated PI hydrolysis in the rat choroid plexus. Ethanol withdrawal (24 h) after chronic ethan ol consumption (15 days) results in the down-regulation of 5-HT2A rece ptors and in a decrease in 5-HT-stimulated PI hydrolysis in the rat co rtex. Taken together, these results, along with other reports in the l iterature, suggest that 5-HT2A/2C, receptors or their function are alt ered during chronic ethanol consumption and withdrawal. Further studie s are needed to explore the role of 5-HT2A/2C, receptors and the PI si gnal transduction system in the development of ethanol withdrawal symp toms after chronic ethanol consumption.