de Vente J, Bast A, Van Bree L, Zaagsma J
Eur J Pharmacol. 1980 Apr 11;63(1):73-83. doi: 10.1016/0014-2999(80)90118-1.
The nature of the rat adipocyte beta-adrenoceptor was studied in further detail using a selected series of tolamol-type beta-adrenoceptor antagonists. Isoprenaline antagonism by these compounds was evaluated on adipocytes, right atrium, left atrium and left hemidiaphragm of the rat. Adipocyte pA2 values were corrected for binding to bovine serum albumin determined separately for each antagonist. A strong correlation between adipocyte and diaphragm pA2 values was found with those antagonists which had an identical N-substituent but a different substitution pattern in the phenoxypropanolamine ring. This relationship was absent with those compounds which had the same 2-methylphenoxypropanolamine moiety but a different N-substituent. With the latter antagonists, however, adipocyte pA2 values correlated significantly with the two cardiac pA2 values. These results support the idea that the interaction site of the rat adipocyte beta-adrenoceptor for the aromatic moiety of arylethanolamines and aryloxypropanolamines has beta 2-characteristics whereas the alkanolamine side-chain interaction site has a beta 1-nature. Finally, it was ascertained that the apparently dualistic (beta 1 and beta 2) character of the rat adipocyte adrenoceptor is not due to the presence of both a beta 1- and a beta 2-receptor population on the fat cell plasma membrane.
使用一系列选定的托拉洛尔型β-肾上腺素能受体拮抗剂，对大鼠脂肪细胞β-肾上腺素能受体的性质进行了更深入的研究。评估了这些化合物对大鼠脂肪细胞、右心房、左心房和左半膈肌的异丙肾上腺素拮抗作用。针对每种拮抗剂分别测定其与牛血清白蛋白的结合情况，对脂肪细胞的pA2值进行了校正。对于那些在苯氧丙醇胺环中具有相同N-取代基但取代模式不同的拮抗剂，发现脂肪细胞和膈肌的pA2值之间存在很强的相关性。对于那些具有相同的2-甲基苯氧丙醇胺部分但N-取代基不同的化合物，这种关系不存在。然而，对于后一种拮抗剂，脂肪细胞的pA2值与两个心脏的pA2值显著相关。这些结果支持这样一种观点，即大鼠脂肪细胞β-肾上腺素能受体与芳基乙醇胺和芳氧基丙醇胺的芳香部分的相互作用位点具有β2特性，而链烷醇胺侧链相互作用位点具有β1性质。最后，确定大鼠脂肪细胞肾上腺素能受体明显的二元性（β1和β2）特征并非由于脂肪细胞质膜上同时存在β1和β2受体群体。
