NEUROHUMORAL CARDIOVASCULAR-RESPONSES TO ALCOHOL AND THEIR MODULATIONBY PERORAL FLUID

Reports on the physiologic effects of acute alcohol are far from unifo rm and probably reflect differences in study designs, which seldom or never consider the effects of coadministered volumes. We therefore mea sured blood pressure, heart rate, and heart rate variability (HRV) by power spectrum analysis, baroreceptor sensitivity, arterial blood flow , pulsed-wave velocity (PWV)I and plasma levels of vasoactive hormones according to 2 protocols: group A = alcohol, 1 g/kg body weight, mixe d with 500 mi of juice; and group B = similar to A plus 750 mi of mine ral water. Each group comprised 9 healthy men, studied before and duri ng the subsequent 1 and 1/2 hours after finishing the alcohol. In A, b ut not in B, alcohol increased heart rate (p = 0.01) and lowered systo lic pressure (p <0.05). Plasma renin activity decreased only in B (p < 0.01). Atrial natriuretic factor decreased in A, but increased in B (b oth p <0.02). Pancreatic polypeptide decreased (both p <0.001), and ca techolamines did not change. In both groups, alcohol reduced PWV and i ncreased blood flow. Baroreceptor sensitivity and the high-frequency b and of HRV decreased in both groups. The physiologic response to acute administration of alcohol appears to depend on the volume of coadmini stered volumes. Alcohol further appears to interfere with vagal, rathe r than with sympathetic activity. (C) 1998 by Excerpta Medico, Inc.