ABSTRACT
To investigate the effects of Pogostemon cablin(patchouli) on gastrointestinal function of rats with the syndrome of damp retention in middle-jiao, and explore its therapeutic mechanism. In this study, gastrointestinal function of rats with the syndrome of damp retention in middle-jiao was evaluated by multiple assays including gastric remnant rate, small intestine propelling rate, gastric juice quantity, pepsin activity and gastrointestinal tissue morphology. ELISA was used to detect gastrointestinal hormones including MTL, GAS, VIP and cytokines including TNF-α and interleukin 10 in rat serum. Real-time fluorescent quantitative PCR technique was used to detect relative mRNA expression of AQP3, AQP4 and AQP8 in gastric and colonic tissues to explore the mechanism of P. cablin in treatment of gastrointestinal functions. The results showed that middle and high dose of P. cablin (3.24, 6.48 g•kg⁻¹) could obviously decrease the gastric remnant rate, promote gastric emptying, increase the small intestine propelling rate(P<0.05), speed up the propulsive movement of gastrointestinal tract, increase the secretion and acidity of gastric juice, increase the activity of pepsin, and improve the injury of gastrointestinal tissue. All the doses of P. cablin could increase the concentration of MTL and GAS in serum, reduce the concentration of VIP, TNF-α and IL-10 in serum, decrease the mRNA expression of AQP3 in gastric and colonic tissues, and increase the expression levels of AQP4 and AQP8 in colonic tissues. The regulatory effects were better in middle and high dose groups. In conclusion, regulation of the levels of gastrointestinal hormones, inflammatory cytokines and aquaporins may be the paths for P. cablin to maintain normal gastrointestinal function of rats with the syndrome of damp retention in middle-jiao. The results of the study laid a foundation for clarifying the treatment mechanism of aromatic damp-resolving drugs for indications including damp retention in middle-jiao and transformation failure of spleen.