Physiological disposition of 3-acetyl-3H.3-acetyl-aconitine in mice

The concentration –time curve of [3-acetyl-3H]3-acetylaconitine(AAc) of ive bolus 4.5 MBq/kg in mice was found to be a triexponential model. The pharmacokinetic parameters calculated according to 3-compartment open model were: pi=0.345/min, alpha=0.057/min, beta=0.009/min,t(1/2pi)=2.0 min, t(1/2alpha)=12.2 min, t(1/2beta)=73.9 min, K12=0.112/min, K21=0.096/min,K13=0.078/min, K31=0.018/min, K10=0.108/min, the central volume(Vc)=0.221 l/kg, clearance (D/AUC)=23.8 ml/min/kg. The radioactivities of AAc iv revealed that the highest level in the bile, moderate in the liver, kidney and lungs, lower in the heart and the lowest in brain.In pregnant mice,the small amounts of radioactivity was shown in the fetus after iv AAc. Absorption of AAc from gastrointestinal tract was found to be fairly rapid,35.4% of the dose was absorbed in 15 min after administration. In 7 d after iv AAc, 43.9% of the radioactivity was extracted in urine and 17.6% in feces. The drug-plasma binding rate was found to be 28.5%. Paper radiochromatograms and ion-pair thin-layer chromatography of urine after iv AAc revealed that the drug was excreted partially in prototype and its metabolite respectively.