Effect of emodin on small intestinal peristalsis of mice and relevant mechanism.

Medical and Pharmacological Institute, Yangzhou University, Yangzhou 225001, Jiangsu Province, China.
World Journal of Gastroenterology (Impact Factor: 2.55). 06/2005; 11(20):3147-50.
Source: PubMed

ABSTRACT To investigate the effect of emodin on small intestinal peristalsis of mice and to explore its relevant mechanisms.
The effect of emodin on small intestinal peristalsis of mice was observed by charcoal powder propelling test of small intestine. The contents of motilin and somatostatin in small intestine of mice were determined by radioimmunoassay. The electrical potential difference (PD) related to Na+ and glucose transport was measured across the wall of reverted intestinal sacs. Na+-K+-ATPase activity of small intestinal mucosa was measured by spectroscopic analysis.
Different dosages of emodin can improve small intestinal peristalsis of mice. Emodin increased the content of motilin, while reduced the content of somatostatin in small intestine of mice significantly. Emodin 0.2, 0.4, 0.8, and 1.6 g/L decreased PD when there was glucose. However, emodin had little effect when glucose was free. The Na+-K+-ATPase activity of small intestinal mucosa of mice in emodin groups was inhibited obviously.
Emodin can enhance the function of small intestinal peristalsis of mice by mechanisms of promoting secretion of motilin, lowering the content of somatostatin and inhibiting Na+-K+-ATPase activity of small intestinal mucosa.

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