Pharmacokinetics, tissue distribution, excretion, and metabolism of a new cardioprotective agent 10-O-dimethylaminoethylginkgolide B in rats

The plasma pharmacokinetics, tissue distribution, excretion, and metabolism of 10-O-dimethylaminoethylginkgolide B (XQ-1H), a protective agent against cardiovascular accident for its potential anti-platelet-activating factor activity, were investigated in rats. Plasma profiles were obtained after intravenous administration of 4, 8, 16, and 32 mg/kg of XQ-1H. There was a gender difference in the pharmacokinetics of XQ-1H. The elimination half-life of XQ-1H was 209.55, 200.81, 236.95, and 269.78 min in female rats and was 139.63, 173.83, 191.28, and 228.0 min in male rats at doses of 4, 8, 16, and 32 mg/kg, respectively. At four dose levels, female rats have higher values for area under the curve (AUC) than male rats. XQ-1H had linear pharmacokinetic characteristics in rats within the dose ranges tested. The volume of distribution in rats ranged from 6.05 to 15.09 1/kg. XQ-1H showed an extensive distribution into multiple tissues and reached its maximal concentration in all tissues at 10 min post-dose. About 80% of XQ-1H was mainly converted to its hydrolyzed and demethylated metabolites in vivo, and the elimination of unchanged compound was minor (< 20%) in rats.