Watanabe Y, Itoh T, Yoshida H
Jpn J Pharmacol. 1980 Jun;30(3):287-91. doi: 10.1254/jjp.30.287.
The developmental change of beta-adrenergic receptors in rat whole brain, except the cerebellum, was studied by binding assays with (--) 3H-dihydroalprenolol. The synaptic membrane fraction, prepared from 2-day-old and 6-week-old rat brains, had binding sites for (--) 3H-dihydroalprenolol, which seemed to represent physiological beta-adrenoceptors. The maximal binding capacity and the dissociation constant for (--) 3H-dihydroalprenolol of the synaptic membrane fraction did not vary with the age of the rats, but the yield of synaptic membrane fraction from the brain of 2-day-old rats was much less. Therefore, the total number of binding sites was less in 2-day-old rats. In addition, there was a significant difference in the inhibitory effects of 1-isoproterenol on binding of (--) 3H-dihydroalprenolol to the synaptic membrane fractions in the 2-day as compared to the tissues from the 6-week-old animals. The developmental changes in the number and nature of beta-adrenoceptors may result in expression of catecholamine-sensitive adenylate cyclase activity.
采用（--）³H - 二氢心得舒结合分析法，研究了大鼠全脑（小脑除外）中β - 肾上腺素能受体的发育变化。从2日龄和6周龄大鼠脑中制备的突触膜组分具有（--）³H - 二氢心得舒的结合位点，这些位点似乎代表生理性β - 肾上腺素能受体。突触膜组分对（--）³H - 二氢心得舒的最大结合容量和解离常数不随大鼠年龄而变化，但2日龄大鼠脑制备的突触膜组分产量要少得多。因此，2日龄大鼠的结合位点总数较少。此外，与6周龄动物的组织相比，1 - 异丙肾上腺素对2日龄大鼠突触膜组分结合（--）³H - 二氢心得舒的抑制作用存在显著差异。β - 肾上腺素能受体数量和性质的发育变化可能导致儿茶酚胺敏感的腺苷酸环化酶活性的表达。
