本实验表明.在豚鼠左心房,苄基四氢巴马汀(BTHP)表现为正性肌力作用,而己吡氰胍(pinacidil)则表现为负性肌力作用。但二者均可抑制肾上腺素所诱发的自律性。在气管,BTHP可使乙酰胆碱(Ach)及组胺(histamine)致气管收缩的量效曲线左移.其左移程度以低剂量时最为明显.与此相反。己吡氰胍则使Ach及组胺的量效曲线右移.最大反应基本不变。当苄基四氢巴马汀与己吡氰胍同时存在时,则Ach及组胺的量效曲线基本不变.提示二药可能作用于气管的同一部位。 This experiment shows that in the left atrium of guinea pigs, benzyl tetrahydropalmatine (BTHP) shows a positive inotropic effect, while pinacidil shows negative inotropic effects. But both can inhibit adrenaline-induced self-regulation. In the trachea, BTHP left the dose-response curve of tracheal contraction induced by acetylcholine (Ach) and histamine to the left, most notably at low doses. Hexopyrenamide shifted the dose-response curve of Ach and histamine to the right, and the maximum response remained essentially unchanged. When benzyltetrahydropalmatine coexisted with hexamethonium, the dose-response curve of Ach and histamine remained unchanged, suggesting that the two drugs might act on the same part of the trachea.