Darroch S A, Choo L K, Mitchelson F
School of Pharmacology, Victorian College of Pharmacy (Monash University), Parkville, Australia.
Naunyn Schmiedebergs Arch Pharmacol. 1992 Mar;345(3):288-95. doi: 10.1007/BF00168689.
The ability of several selective muscarine receptor antagonists to inhibit the effect of carbachol on prejunctional muscarine receptors on sympathetic nerve endings in the rabbit isolated ear artery was investigated to characterise the receptor subtype involved. Carbachol did not reduce responses to exogenous noradrenaline and the inhibitory effect of carbachol on responses to nerve stimulation was unaffected by hexamethonium (10 microM) indicating that the effect of the muscarine agonist was exerted prejunctionally and was not modulated by nicotine receptor stimulation. The dissociation constants or apparent dissociation constants obtained using (+/-)-benzhexol (pKB; 6.63), (R)-benzhexol methiodide (8.11), dicyclomine (5.86), (+/-)-telenzepine (7.34), AF-DX 116 (6.95), himbacine (7.60), (+/-)-hexahydrosiladiphenidol (5.39) and a bisquaternary ammonium compound, heptane-1,7-bis(dimethyl-3'-phthalimidopropyl ammonium bromide) (5.84), indicate that the muscarine receptor subtype involved is not of the M1, M2 or M3 subtype.
研究了几种选择性毒蕈碱受体拮抗剂抑制卡巴胆碱对兔离体耳动脉交感神经末梢节前毒蕈碱受体作用的能力，以确定所涉及的受体亚型。卡巴胆碱不降低对外源性去甲肾上腺素的反应，且卡巴胆碱对神经刺激反应的抑制作用不受六甲铵（10微摩尔）影响，这表明毒蕈碱激动剂的作用是在节前发挥的，且不受烟碱受体刺激的调节。使用（±）-苯海索（pKB；6.63）、（R）-苯海索甲碘化物（8.11）、双环维林（5.86）、（±）-替仑西平（7.34）、AF-DX 116（6.95）、樟柳碱（7.60）、（±）-六氢硅哌啶醇（5.39）和一种双季铵化合物庚烷-1,7-双（二甲基-3'-邻苯二甲酰亚胺丙基溴化铵）（5.84）获得的解离常数或表观解离常数表明，所涉及的毒蕈碱受体亚型不是M1、M2或M3亚型。
