国产乙酰普马嗪的药理作用研究——加强作用及对交感神经末梢介质释放的影响

(1)采用热水刺激小白鼠尾巴法試驗鎮痛作用,乙酰普馬嗪0.5毫克/公斤可使“疼痛”反应出現时間延迟,較盐酸嗎啡(2毫克/公斤)为弱;二者均以半量合并应用,鎮痛作用强度虽未見加强,但鎮痛时間則延长。(2)脑室內注射乙鮂振R嗪,可立即引起小白鼠安靜,并使其体溫明显下降;皮下注射同剂量时,安靜及降溫作用均不显著,但可明显加强安替比林及水合氯醛的降溫作用。(3)乙酰普馬嗪局部滴药及皮下注射均可产生角膜麻醉,并可加强普魯卡因的表面麻醉作用,尤以皮下注射法为强。(4)乙酰普馬嗪2.5微克/公斤即可減弱腎上腺素的升压作用;5微克/公斤时,使后者作用翻轉,并使电刺激交感神經节前纤維及注射腎上腺素所引起的瞬膜收縮反应減弱。(5)在离体兔神經——迴腸标本,电刺激交感神經节后纤維引起腸张力下降,运动減弱,乙酰普馬嗪及氯丙嗪均可加强此交感反应。

SOME PHARMACOLOGICAL PROPERTIES OF ACEPROMAZINE:ITS POTENTIATING ACTION AND ITS EFFECT ON THE RELEASE OF THE TRANSMITTER FROM THE POST-GANGLIONIC SYMPATHETIC NERVE FIBRES

(1) The analgesic potency of acepromazine in a dose of 0.5 mg/kg was somewhat inferior to that of morphine (2mg/kg). By combining these two drugs, the analgesic effect was summated and the duration of action was prolonged. (2) After intracerebral injection, acepromazine produced more prominent tranquilizing and hypothermic effects than those elicited by hypodermic administration. It could also potentiate the hypothermic action of chloral hydrate and antipyrin. (3) Acepromazine, applied locally or injected subcutaneously, produced definite surface anaesthesia in rabbit's cornea and potentiated the anaesthetic action of procaine. (4) The vasopressor response to 5 γ/kg of adrenaline in the anaesthetized cats was reduced by 2.5 γ/kg of acepromazine and reversed by 5 γ/kg of the antagonist. The contraction of the nictitating membrane due to preganglionic sympathetic stimulation and injection of adrenaline was reduced by the larger dose. (5) When the periarterial nerves of Finkleman's preparation were stimulated, the motor activity of the isolated rabbit's ileum was decreased and the tone was reduced. This inhibitory response to the nerve stimulation was potentiated by acepromazine and chlorpromazine in the concentrations of 1:1,000,000-4:1,000,000. It is concluded that acepromazine and chlorpromazine do not interfere, with the release of noradrenaline from the post-ganglionic sympathetic nerve endings.