Pharmacokinetics, tissue distribution, plasma protein binding rate and excretion of sinoacutine following intravenous administration in female and male Sprague-Dawley rats

Sinoacutine is a natural isoquinoline alkaloid isolated from traditional Chinese medicine Stephanina yunnanensis H. S. Lo. Our aim was to study the pharmacokinetic characteristics of sinoacutine, which is essential during the development of new drugs. In this study, an accurate, sensitive, and efficient liquid chromatography (HPLC) method was developed and applied to evaluate the pharmacokinetics, tissue distribution, plasma protein binding rate, and excretion after intravenous injection of sinoacutine in rats. The pharmacokinetic parameters of sinoacutine were accorded with a two-compartment model in rats, and the AUC(0-)(t) in female was greater than that in male. Sinoacutine could be detected in heart, liver, spleen, lung, kidney, and brain, and the content in liver and kidney was relatively high. Meanwhile, it had a high plasma protein binding rate of 79.16%. Excretion of sinoacutine through faeces and urine was low, and the average excretion rate was 9.96%. There were gender differences in blood drug concentration, tissue distribution, and excretion significantly (p < 0.05). In summary, this study lays a foundation for elucidating the pharmacokinetic rule of sinoacutine and the data can provide a reliable scientific resource for further research.