Effects of ethanol and its interaction with vasoactive agents in bovine vascular smooth muscle

The vascular effects of ethanol were evaluated using isolated arteries from bovine brain, eye, and kidney. Ethanol induced contraction in all vessels, but only at concentrations in excess of lethal blood levels in man. At a concentration approximating that found in the blood during intoxication (43 mM), ethanol had no effect on renal vascular responses to norepinephrine, serotonin, or histamine. The response of ocular vessels to norepinephrine and histamine was significantly diminished by 43 mM ethanol, suggesting a possible mechanism underlying the "bloodshot" eyes found in acute intoxication. Cerebral vascular responses to vasoactive agents were generally unaffected by 43 mM ethanol, indicating that regional differences in brain perfusion are probably not a cause of the behavioral changes found during intoxication.