In vivo and in vitro effects of Salsola collina on gastrointestinal motility in rats

Objective(s): Salsola collina is widely distributed along the Bohai coast and consumed as an edible plant by native residents. We have found surprisingly that S. collina extracts promoted gastrointestinal motility in mice previously. In the present study, effects of S. collina on gastrointestinal motility in rats and its underlying mechanism were explored. Materials and Methods: In vivo, different fraction extracts from S. collina were prepared and the effects on gastric emptying and small intestinal propulsion in normal rats were measured. Plasma ghrelin (GRL), motilin (MTL), gastrin (GAS) and vasoactive intestinal peptide (VIP) and expressions of GRL receptor (GHSR), MTL receptor (MTLR), VIP receptor 2 (VIPR2) in the duodenum were also detected. In vitro, gastric antrum strips were prepared and activities of different extracts on gastric smooth muscle contractions were evaluated. Results: Results showed that the ethyl acetate extract (EAE) was the most effective fraction to promote gastric emptying and intestinal propulsion, showing a dose-dependent manner. EAE increased plasma GRL and GAS, elevated GHSR expression and restrained VIPR2 expression in the duodenum. In vitro, EAE promoted contraction of normal gastric antrum strips as well as relaxed strips induced by atropine. Conclusion: These data indicate that EAE has a significant prokinetic activity via a mechanism that mainly involves in modulating plasma GRL and GAS, expressions of GSHR and VIPR2 in the duodenum and activating M-cholinergic receptor. Our study provides a pharmacological basis for the use of S. collina extract in treating gastrointestinal motility disorders.