Biotransformation of lisuride in the hemoglobin-free perfused rat liver and in the whole animal.

Isolated rat livers were perfused with an oxygenated saline medium containing 14C-lisuride. Metabolites obtained in the bile and the perfusate were characterized as the glucuronide of hydroxylisuride and hydroxy, 2-oxo, monode-ethyl, dide-ethyl, N6-demethyl and monode-ethyl-N6-demethyl derivatives of lisuride. In addition, the metabolite patterns were examined in various tissue homogenates in vitro and also in the rat in vivo. Whereas dealkylation reactions occurred predominantly under in vitro conditions, the metabolite profile observed in vivo was similar to that found in the perfused liver system. The principal routes for biotransformation of lisuride in the intact rats as well as in the perfused rat liver are those through aromatic hydroxylation and subsequent conjugation with glucuronic acid.