The effect of drinking habit on catecholamine and behavioral responses to stress and ethanol.

The effects of alcohol tolerance on stress sensitivity to venipuncture and mental arithmetics, on acute ethanol effects, and on ethanol-induced modifications of stress responses were tested in 44 healthy male volunteers selected according to a questionnaire as 22 high (HC) and low (LC) habitual consumers of alcohol each. Plasma epinephrine (E) and norepinephrine (NE), mood check lists, and performance scores were obtained at two mental arithmetic stressors, one applied before and one after their intake of 0.8 g/kg of ethanol or a respective placebo drink. HC were less responsive with both E and NE to venipuncture and to mental stress regarding emotional and NE changes though showing higher E increases. Ethanol blood levels in HC were higher but ethanol-induced NE changes lower than in LC. The E, NE, and emotional stress responses were less reduced and performance less impaired by ethanol in HC than in LC. This was taken as evidence that neither stress nor ethanol sensitivity is increased in alcohol-preferring subjects but that tolerance by chronic intake of moderate doses of alcohol will result in a reduced efficacy of ethanol both on the psychological and biochemical levels, although effects on these two levels have not been found to be intraindividually related.