The researchers conducted parallel studies in human subjects and nonhuman primates to examine the differential effects of tobacco and nicotine smoking on changes in GABA(A) receptor availability during acute and prolonged alcohol withdrawal.
They report that alcohol withdrawal with or without concurrent tobacco smoking/nicotine use resulted in significant increases in GABA(A) receptor levels during the first week of withdrawal. After prolonged withdrawal, GABA(A) receptor levels returned to normal in alcohol-dependent nonsmokers, but alcohol-dependent smokers had significant and persistent increases in GABA(A) receptors associated with craving for alcohol and cigarettes.
These data suggest that tobacco smoke constituents other than nicotine block recovery of GABA(A) receptor systems during sustained alcohol abstinence, contributing to alcohol relapse and smoking maintenance.
Tobacco smoking interferes with GABAAreceptor neuroadaptations during prolonged alcohol withdrawal.
