[Effect of emodin on motility signal transduction in colonic smooth muscle cells in rats with multiple organ dysfunction syndrome].
OBJECTIVE
To observe the effect of emodin on motility signal transduction and calcium ion in colonic smooth muscle cells (SMC) in rats with bacterial peritonitis caused multiple organ dysfunction syndrome (MODS).


METHODS
Observation was conducted in colon of MODS model rats on (1) effects of emodin on the contraction of muscular strip and cells of colonic smooth muscle, and influences of specific myoglobulin light chain kinase inhibitor (ML-7) and selective proteinkinase C inhibitor (Calphostin C) on these effects; and (2) effect of emodin on calcium ion in SMC.


RESULTS
Emodin could directly contract the muscular strip and cells of smooth muscle; ML-7 and Calphostine could inhibit these contractile action to some extent. Under MODS condition, emodin could still increase the intracellular calcium ion concentration; this effect could be inhibited by heparin (inosamine triphosphate receptor inhibitor IP3 and ryanodine receptor inhibitor in MODS model but the calcium chelator EGTA and nifedipine (the specific cell membrane voltage dependent calcium channel blocker) showed no influence on it.


CONCLUSIONS
Emodin could directly contract the colonic smooth muscle in MODS model rats, which is mediated by raise the signal path MLCK of calcium ion and the PKCa path for increase calcium sensibility. The mechanism of increasing calcium ion is mainly through IP3 and RyR the two calcium ion channel receptor in the sarcoplasm.
Chen
Zhe-Yu
ZY
zheyuchen@sina.com.cn
Qi
Qing-Hui
QH
Ma
Tao
T
Jian
Xu
X
D000818:Animals; D002118:Calcium / Q000378:metabolism; D003106:Colon / Q000187:drug effects; D004642:Emodin / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005769:Gastrointestinal Motility / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D009102:Multiple Organ Failure / Q000503:physiopathology*; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000166:cytology / Q000187:drug effects*; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction
D004791:Enzyme Inhibitors; D004642:Emodin; D002118:Calcium