Dage R C
Br J Pharmacol. 1979 Jan;65(1):15-21. doi: 10.1111/j.1476-5381.1979.tb17328.x.
1 Oxotremorine, methyloxotremorine, pilocarpine or arecoline were given intravenously to anaesthetized cats, dogs or rats, and intraperitoneally to conscious normotensive and spontaneously hypertensive rats, pretreated with doses of methylatropine that completely blocked peripheral muscarinic receptors, to ascertain their effects on blood pressure and heart rate.2 Oxotremorine but not methyloxotremorine produced a prolonged hypotension in cats and dogs but not in rats. Heart rate was not changed. Pilocarpine, although less potent, produced an identical effect, whereas the effect of arecoline was short by comparison. The hypotensive effect of these drugs was reversed by atropine.3 In dogs, oxotremorine produced a prolonged hypotension with no change in heart rate or cardiac output.4 A decrease in spontaneous sympathetic nerve activity accompanied the hypotension in cats. Both effects were reversed by atropine but could be reinvoked by large doses of oxotremorine.5 The oxotremorine-induced hypotension in cats was not altered by decerebration but was abolished by high cervical spinal section.6 The results indicate that the prolonged hypotension elicited by oxotremorine is mediated by an action at muscarinic receptors in the brain stem resulting in a decrease in sympathetic nerve activity and peripheral resistance but not heart rate or cardiac output.
将氧化震颤素、甲基氧化震颤素、毛果芸香碱或槟榔碱静脉注射给麻醉的猫、狗或大鼠，并腹腔注射给清醒的正常血压和自发性高血压大鼠，这些大鼠预先给予能完全阻断外周毒蕈碱受体的甲基阿托品剂量，以确定它们对血压和心率的影响。
氧化震颤素而非甲基氧化震颤素在猫和狗身上产生了长时间的低血压，但在大鼠身上未产生。心率未改变。毛果芸香碱虽然效力较弱，但产生了相同的效果，而槟榔碱的效果相比之下较为短暂。这些药物的降压作用可被阿托品逆转。
在狗身上，氧化震颤素产生了长时间的低血压，心率和心输出量没有变化。
猫的低血压伴随着交感神经自发活动的降低。这两种效应都可被阿托品逆转，但大剂量的氧化震颤素可再次引发。
猫中氧化震颤素诱导的低血压不受去大脑的影响，但可被高位颈髓横断所消除。
结果表明，氧化震颤素引发的长时间低血压是由脑干中对毒蕈碱受体的作用介导的，导致交感神经活动和外周阻力降低，但心率和心输出量不变。
