Increased urinary folate excretion and decreased plasma folate levels in the rat after acute ethanol treatment.

A common complication of chronic alcohol abuse is folic acid deficiency, which can result from poor dietary intake and from a direct effect of ethanol on folate metabolism, such as the acute decrease in serum folate levels. Ethanol (4 g/kg body weight) was administered orally to male Sprague-Dawley rats to study the rat as a suitable animal model for the acute effects of ethanol. The concentration of folate in the urine, determined by Lactobacillus casei assay, as well as the amount of urinary folate excretion were markedly increased 4 hr after ethanol administration. After 14 hr, the total plasma folate level was significantly depressed to 50% of control levels. No significant changes were observed in the total folate levels in the liver and red cell nor in the levels of individual hepatic folate monoglutamate derivatives determined by high pressure liquid chromatography assay. These results indicate that acute ethanol administration to rats produces a marked increase in the urinary excretion of folate compounds, which leads to a decrease in plasma folate levels. The acute decrease in plasma folate levels in ethanol-treated rats is similar to that seen in humans and suggests that the rat is an appropriate model for the study of the acute effects of ethanol on folate metabolism.