Pharmacokinetic behavior of 16-dehydropregnenolone after intramuscular administration in rats

The pharmacokinetics of 16-dehydropregnenolone (16-DHP), a sterols compound isolated from Solanum lyratum Thunb., was investigated in rats following a Single intramuscular administration (40 mg/kg). The concentration of 16-DHP in rat plasma was determined by a high Performance liquid chromatography (HPLC) method with UV detection. Levonorgestrel was used as the internal Standard (IS). The pharmacokinetic parameters of 16-DHP were derived by non-compartmental method. After a Single intramuscular administration, the maximum plasma concentration (C(max)) was (289 ± 25) ng/mL, time to reach C(max)(t(max)) was (0.38 ± 0.14) h, the elimination half-life (t(1/2)) was (2.5 ± 1.1) h, the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUC((0-t))) was (544 ± 73)ng · h/mL. The results indicated that 16-DHP was absorbed quickly and eliminated rapidly in rats after the intramuscular injection.