Blood acetaldehyde concentration gradient between hepatic and antecubital venous blood in ethanol‐intoxicated alcoholics and controls*

After ethanol (0.8 g kg-1 body weight orally) significant concentrations of acetaldehyde (2-20 mumol 1(-1] were found in hepatic venous blood of moderately intoxicated non-alcoholic male Caucasians in spite of the absence of detectable levels (less than 2 mumol 1(-1] in simultaneously taken antecubital blood. In thirteen chronic alcoholics the elevation of blood acetaldehyde was more constant in the hepatic than in the peripheral vein. Fructose infusion caused a marked elevation of acetaldehyde both in the hepatic and peripheral vein of four controls, but not of four alcoholics, who eliminated ethanol about 50% faster than controls. The rate of disappearance of acetaldehyde from sampled and in vitro incubated hepatic venous blood was similar to that observed after addition of acetaldehyde in vitro to ethanol-free control blood (2 nmol ml-1 min-1 at 20 mumol 1(-1) acetaldehyde; Km about 30 mumol 1(-1]. Uptake of acetaldehyde in blood was calculated to explain maximally 30-40% of the concentration gradient between central and peripheral blood.