1. This study examines the response of blood pressure, plasma catecholamines and cortisol to acute alcohol intake in young men with light to moderate drinking habits.
2. Ingestion of alcohol was associated with a highly significant increase in systolic blood pressure and heart rate which occurred before blood alcohol reached its peak concentration of 16.9 ± 1.1 mmol/l (80 mg/100 ml). After an initial non-specific rise, diastolic pressure fell below values observed after drinking water only. This predominant effect of alcohol on systolic blood pressure is also seen with chronic alcohol consumption.
3. Drinking water and non-alcoholic cold liquids caused a marked fall in plasma adrenaline and a transient rise in noradrenaline concentration. In contrast, drinking alcohol resulted in a relative rise in adrenaline and a delayed increase in noradrenaline concentration.
4. Blood glucose increased after alcohol, supporting a physiological effect of adrenaline on liver glycogenolysis. Plasma cortisol concentration was also significantly higher after drinking alcohol.
5. It is proposed that the relative rise in adrenaline together with higher cortisol levels, repeated over a variable period in susceptible individuals, are implicated in the elevation of blood pressure associated with long term alcohol consumption. It concurs with observations in man and experimental animals of a slow pressor mechanism mediated by adrenaline.
6. The study emphasized that an evaluation of the acute effects of alcohol requires careful measurement of blood pressure, precise assay of catecholamines and recognition of the confounding effects of drinking cold liquids.