Lefever G S, Green R D
J Pharmacol Exp Ther. 1975 Jun;193(3):739-47.
The EC50 values, KA values and efficacies (e) of selected agonists have been determined in strips of stomach muscularis from control, chlorisondamine-pretreated and O, O-diethyl S[2(ethylthio)ethyl]phosphodithioate (disulfoton)-pretreated rabbits. Strips from chlorisondamine-pretreated animals were supersensitive to carbachol but normosensitive to phenylephrine; the e but the KA of carbachol was affected by this treatment. The KB of atropine was unchanged. Strips from animals treated with disulfoton were subsensitive to phenylephrine but normosensitive to amidephrine and carbachol; both the e and KA of phenylephrine appeared to be elevated by this pretreatment. The KB of phentolamine remained unchanged. These results indicate that the chlorisondamine-induced supersensitivity is the result of a change beyond the level of the cholinergic receptors. In contradistinction, the subsensitivity to phenylephrine after disulfoton pretreatment may result at least in part, from a qualitative change in the alpha adrenergic receptors in the stomach muscularis.
已在来自对照兔、经氯异吲哚明预处理的兔以及经O,O-二乙基S-[2-(乙硫基)乙基]二硫代磷酸酯（乙拌磷）预处理的兔的胃肌条上测定了所选激动剂的半数有效浓度（EC50）值、亲和常数（KA）值和效能（e）。来自经氯异吲哚明预处理动物的肌条对卡巴胆碱超敏感，但对去氧肾上腺素正常敏感；卡巴胆碱的效能（e）但不是亲和常数（KA）受此处理影响。阿托品的解离常数（KB）未改变。经乙拌磷处理动物的肌条对去氧肾上腺素不敏感，但对间羟胺和卡巴胆碱正常敏感；去氧肾上腺素的效能（e）和亲和常数（KA）似乎因这种预处理而升高。酚妥拉明的解离常数（KB）保持不变。这些结果表明，氯异吲哚明诱导的超敏感性是胆碱能受体水平以上变化的结果。相反，乙拌磷预处理后对去氧肾上腺素的不敏感性可能至少部分是由于胃肌条中α肾上腺素能受体的质性变化所致。
