NO isn't involved in the effect of TMP on vasomotion of arterioles in the rabbit mesentery / 中国病理生理杂志

ABSTRACT

AIM: To elucidate the role of NO in the effect of tetramethylpyrazine (TMP) on vasomotion of arterioles induced by noradrenalin(NA).METHODS: Albino rabbits were anesthetized,respiration were maintained,the arterial pressure were measured with a pressure transducer attached to a polyethylene canula in the left common carotid artery,the intestinal loop was mounted on the stage of an inverted microscope and bathed in balanced solution.The inside diameter of the arterial was manually measured on a TV monitor using the TV camera mounted on the microscope.RESULTS: Topical applicated NA to measured field inducd spontaneous vasomotion which has frequency and amplitude.TMP inhibited vasomotion in vasodilation. Treatment with L-NMMA did not affect the effect of TMP.CONCLUSION: L-NMMA can not inhibit action of TMP on vasomotion,TMP may act on smooth muscle directly, not through endogenous NO.