[Effect of morphine chloride on contractility of small intestinal muscle in vitro or in vivo and its mechanisms].
To investigate the effect of morphine chloride on small intestinal muscle in vitro or in vivo and its mechanisms.



Contractile amplitude, tension and frequency of the isolated small intestine of rabbits were measured before and after treatment of morphine chloride. The propulsive distance of magenta in intestinal tract was measured when different concentration of morphine chloride was given orally in mice.



After treatment of different concentration of morphine chloride (5 mg/L, 10 mg/L, 30 mg/L), the contractile activities of isolated small intestines of rabbits decreased significantly. The inhibitory effect of morphine chloride was blocked by naloxone, atropine, but potentiated by regitine. The propulsive distance of magenta in intestinal tract of intact mouse decreased after treatment with morphine chloride of various concentration (75, 150, 300 mg/L).



Morphine chloride has an inhibitory effect on the contractility of rabbit small intestine in vitro or in vivo. Opioid receptor, choline and adrenal receptor might be involved in this effect.
Department of Physiology, College of Medicine, Zhejiang University, Hangzhou 310058, China.
Zhi-Ying
ZY
Feng
Lian-Gen
LG
Mao
Yuan
Y
Lu
D000818:Animals; D005260:Female; D005772:Gastrointestinal Transit / Q000187:drug effects*; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000187:drug effects*; D008297:Male; D051379:Mice; D009020:Morphine / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D011817:Rabbits
D009020:Morphine