The Inhibitory Effect of Anisodamine Hydrobromide Against Contraction of Intestinal Smooth Muscles Induced by Acetylcholine, With Its Pharmacokinetics and Mechanism Investigation

Objective To investigate the inhibitory effects of Anisodamine hydrobromide (AniHBr) on acetylcholine (ACh)-induced contractions and pharmacodynamics, and the potential mechanism. Methods The inhibitory effect of AniHBr on ACh-induced contraction of isolated rat and rabbit intestinal smooth muscles (n=10) was studied. The average strain was measured by a multiple physiological signal acquisition and processing system equipped with a muscle tension sensor. The plasma drug concentrations in Beagle dogs were detected using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the AniHbr pharmacokinetic profile. Based on network pharmacology, qRT-PCR and Western blot experiment used to detect the expression changes of key factors in IM-R069 cells. Results Results showed that AniHBr significantly inhibited the Ach-induced contraction of rat and rabbit intestinal smooth muscles, reduced the average strain. A peak plasma concentration (C max , 51.01±37.99 ng/mL) of AniHBr was observed within 0.72h post-dose. Moreover, the mean elimination half-life of AniHBr was 1.02 ± 0.19 h. Network pharmacology analysis identified 148 key targets of AniHBr associated with gastrointestinal diseases. qRT-PCR and Western blot experiment showed 20 ug/mL AniHBr significantly increased the mRNA expression of EFGR and STAT3, and suppressed PI3K-AKT signaling pathway. Conclusions AniHBr effectively inhibits Ach-induced contraction of isolated rat and rabbit intestinal smooth muscles, might be through regulating EFGR, STAT3 and PI3K-AKT signaling pathway.