平滑筋に対するTrimetazidine薬理作用に関する実験的研究

第II編モルモット小腸収縮に対するTrimetazidineの抑制作用

抄録

Part I. Actions on the vas deferens preparation
1) Trimetazidine gave scarcely any influence on the tension of the vas deferens preparation, when the drug was given to it independently.
2) Noradrenaline induced the contraction of the preparation and this contraction was potentiated by the pre-addition of trimetazidine.
3) When the tension of the preparat i on had been increased by the noradrenaline addition, the succeeding addition of trimetazidine could induce the contraction as if the more noradrenaline was added there.
4) The vas deferens response to noradrenaline reduced in the calcium-free Locke's solution when the preparation had been kept in this medium for a fairly long time.
5) In high calcium media, the potentiation of the noradrenaline contracti on by trimetazidine in the preparation was more remarkable than that seen in a Locke's solution, but the effect of trimetazidine was not so remarkable in low calcium media.
6) In high or low potassium media, this kind of effect of trimetazidine was as much as that seen in a Locke's solution.
7) In low sodium media, this effect of trimetazidine was much more remarkable than that seen in a Locke's solution, while it was scarcely seen in high sodium media. From these results, it was assumed that the potentiation of the noradren aline contraction by trimetazidine was caused by its action that can increase the available calcium ions released from the tissue, and that this action was manifested in low sodium or high calcium media while suppressed in high sodium media.
Part II. The actions on the small intestine preparation
1) Trimetazidine in high concentrations dec reased the smooth muscular tone and suppressed its spontaneous contractions.
2) Trimetazidine in high concentrations suppressed the actions of barium chloride, nicotine, acetylcholine, serotonin, and histamine on the smooth muscle tone of the small intestine. From these results, it was assumed that trimetazidine has the anti-nicotinic action, and that the drug can suppressed the spontaneous contraction of the smooth muscle in the small intestine through its action suppressing the permeability of calcium or barium ions in the muscle membrane, in a different manner from that seen in the smooth muscle of the vas deferens.