Yagi T, Miyawaki Y, Nishikawa A, Yamauchi K, Kuwano S
Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Hyogo, Japan.
J Pharm Pharmacol. 1991 May;43(5):307-10. doi: 10.1111/j.2042-7158.1991.tb06695.x.
Rhein anthrone (12.48 mg kg-1) produces watery and mucoid diarrhoea approximately 20 min after intracaecal administration to rats. Pretreatment with the prostaglandin (PG) biosynthesis inhibitor indomethacin (10 mg kg-1, i.p.) only delayed and did not completely block the onset of the induced diarrhoea. Rhein anthrone stimulated PGE2 release into the rat colonic lumen and the increased release was depressed by indomethacin. Rhein anthrone also accelerated large intestinal transit and this acceleration could be partly inhibited by indomethacin, which was probably responsible for the delay in the onset of diarrhoea. Indomethacin prevented the enhanced water, K+ and mucus secretion and the reduced Na+ absorption in the colon which were induced by rhein anthrone. The net water secretion could not be reversed to net absorption and the mucus secretion was only slightly depressed by indomethacin. Thus, our findings suggest that other mechanisms, together with the PG-dependent mechanism, are involved in the purgative action of rhein anthrone in rats.
大黄蒽酮（12.48毫克/千克）经盲肠内给药至大鼠后约20分钟，可引起水样和黏液样腹泻。用前列腺素（PG）生物合成抑制剂吲哚美辛（10毫克/千克，腹腔注射）预处理，仅延迟而未完全阻断诱导性腹泻的发作。大黄蒽酮刺激PGE2释放到大鼠结肠腔内，吲哚美辛可抑制这种增加的释放。大黄蒽酮还加速大肠转运，这种加速可被吲哚美辛部分抑制，这可能是腹泻发作延迟的原因。吲哚美辛可防止大黄蒽酮诱导的结肠内水、钾和黏液分泌增加以及钠吸收减少。净水分分泌不能逆转为净吸收，吲哚美辛仅轻微抑制黏液分泌。因此，我们的研究结果表明，除了PG依赖性机制外，其他机制也参与了大黄蒽酮对大鼠的泻下作用。
