Neufeld A H, Page E D
Invest Ophthalmol Vis Sci. 1977 Dec;16(12):1118-24.
Alpha- and beta-adrenergic receptors were studied by measuring the binding of 3H-dihydroergocryptine and 3H-dihydroalprenolol, respectively, to membranes prepared from homogenized rabbit iris--ciliary bodies. The binding of 3H-dihydroergocryptine appears to be specific for alpha-adrenergic receptors, since adrenergic agents displace this radioligand with the following order of potency: phentolamine greater than epinephrine greater than or equal to norepinephrine greater than or equal to isoproterenol = propranolol. The binding of 3H-dihydroalprenolol appears to be specific for beta-adrenergic receptors, since adrenergic agents displace this radioligand with the following order of potency: propranolol greater than or equal to isoproterenol greater than or equal to epinephrine greater than norepinephrine greater than or equal to phentolamine. Clonidine and dopamine bind to the alpha-adrenergic receptor but have little activity at the beta-adrenergic receptor. Timolol, d-isoproterenol, and dipivalyl epinephrine bind to the beta-adrenergic receptor but have little activity at the alpha-adrenergic receptor. The results demonstrate that in vitro binding assays for alpha- and beta-adrenergic receptors are useful for studying the mechanism of drug action.
通过分别测量3H-二氢麦角隐亭和3H-二氢心得舒与兔虹膜-睫状体匀浆制备的膜的结合，对α和β肾上腺素能受体进行了研究。3H-二氢麦角隐亭的结合似乎对α肾上腺素能受体具有特异性，因为肾上腺素能药物以以下效力顺序取代这种放射性配体：酚妥拉明＞肾上腺素≥去甲肾上腺素≥异丙肾上腺素 = 普萘洛尔。3H-二氢心得舒的结合似乎对β肾上腺素能受体具有特异性，因为肾上腺素能药物以以下效力顺序取代这种放射性配体：普萘洛尔≥异丙肾上腺素≥肾上腺素＞去甲肾上腺素≥酚妥拉明。可乐定和多巴胺与α肾上腺素能受体结合，但对β肾上腺素能受体几乎没有活性。噻吗洛尔、d-异丙肾上腺素和二特戊酰肾上腺素与β肾上腺素能受体结合，但对α肾上腺素能受体几乎没有活性。结果表明，α和β肾上腺素能受体的体外结合试验对于研究药物作用机制是有用的。
