[Pharmacological analysis of effects of perimetazine on isolated smooth muscle]

Effects of perimetazine on the motility of the isolated smooth muscle of guinea pig (ileum, taenia coli, uterus, vas deferens and trachea) and the ileum of rabbit were studied. The results obtained are as follows: Perimetazine showed a specific antihistamine, antiadrenaline and antiserotonin action. Moreover, antiacetylcholine and anti-BaC12 actions were observed with high doses of perimetazine as well as chlorpromazine and such actions were attributed to the nonspecific direct action on the smooth muscle. Both the spontaneous movement and the tonus of guinea pig taenia coli were also inhibited by a high concentration of perimetazine. The spontaneous membrane action potentials of the taenia coli recorded by the use of the sucrose-gap method were inhibited by a high concentration of perimetazine both in frequency and in amplitude with relaxation of the tonus. The action potentials were abolished however and change in the resting membrane level was not clearly observed.