[Effect of total anthraquinone in rheum on aquaporin 2 expression in rat distal colon].

OBJECTIVE

To investigate effect of total anthraquinone in rheum on aquaporin 2 expression in rat distal colon.

METHODS

SD rats were randomly divided into control group, low dose group, middle dose group and high dose group. Gavaged to control group, and treated group were administered saline and total anthraquinone in rheum with dosage of 0.14, 2.5, 4.5 g x kg(-1) x d(-1), respectively. All rats were put sacrificed after 5 days and stool in full length colon was gently collected to detect water content stool. Distal colon was removed to detect AQP2 expression with immunohistochemistry, western blot and RT-PCR.

RESULTS

No diarrhea was found in low dose group and control group, there were not significant difference water content of stool and AQP2 expression between low dose group and control group. However, soft feces and loose stools occurred in diarrheic dose group, loose stools and watery stool appeared in high dose group. Stool water content increased in diarrheic dose group and High dose group, expression of AQP2 decreased evidently in these two groups (P < 0.01).

CONCLUSIONS

Total anthraquinone in rheum can reduce the transcription and translation of AQP2 in rats' distal colon, increase fecal water content, which probably is one of the mechanisms of diarrhea caused by total anthraquinone in rheum.