From Scientific American:
Over the past few decades scientists have observed a narrowing of the gender gap in alcohol dependence. In the 1980s the ratio of male to female alcohol dependence stood at roughly five males for every female, according to figures compiled by Shelly Greenfield, a professor of psychiatry at Harvard Medical School. By 2002 the “dependence difference” had dropped to about 2.5 men for every woman. But although the gender gap in dependence may be closing, differences in the ways men and women respond to alcohol are emerging. Writing in the January 2012 issue of Alcoholism: Clinical and Experimental Research, principal investigator Claudia Fahlke from the Department of Psychology at the University of Gothenburg in Sweden and her colleagues found that alcohol's ability to reduce serotonin neurotransmission, was “telescoped” in alcoholic women compared with their male counterparts. In other words, although the alcohol-dependent men and women in the study differed substantially in their mean duration of excessive drinking—four years for the women and 14 years for the men—both sexes showed similar patterns of reduced serotonin activity compared with controls. The researchers gauged serotonergic neurotransmission by measuring its response to citalopram, a drug that stalls serotonin molecules in the synaptic gap (as measured by the hormone prolactin's response to citalopram. This pattern of reduced serotonergic neurotransmission matters, because some of the alcohol-induced abnormalities were found in brain regions involved in judgment, self-control and emotional regulation.
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