Pharmacokinetics of dalargin

: Pharmacokinetics of a new anti-ulcer drug, synthetic opioid hexapeptide dalargin (Tyr-D-Ala-Gly-Phe-Leu-Arg), which is an analogue of Leu-enkephalin, was studied in rats. Distribution and metabolism of 3H-Tyr-dalargin were examined after intravenous administration at a dose of 150 mg/kg. Main Tyr-containing metabolites of dalargin were detected and dynamics of their concentrations was evaluated in blood within 1 hr after administration. Kinetic curve of dalargin was described as three-exponential function.