[Action of levorin on amino acid transport in the rat small intestine].

Levorin, a polyenic antibiotic, in concentration of 2.10(-6) M markedly inhibited the active transport of amino acids in the cells of rat thin intestine, thus decreasing the oxygen dependent transfer of 14C-glycine and 14C-leucine and antigradient accumulation of glycine in the enterocytes. The effect increases with an increase in the period of the intestine mucosa contact with the antibiotic. Introduction of levorin from th serous side had no effect on the glycine transport. Inhibition of the transmembrane transport of glycine by levorin is due to its effect on transfer and accumulation of amino acids in the cells.