Feolde E, Vigne P, Frelin C
Institut de Pharmacologie Moléculaire et Cellulaire--CNRS UPR 411 Université de Nice Sophia Antipolis, Valbonne, France.
J Mol Cell Cardiol. 1993 Nov;25(11):1359-67. doi: 10.1006/jmcc.1993.1148.
The distribution and function of AII receptor subtypes was evaluated in different preparations of rat hearts. Autoradiographic experiments and binding experiments on isolated membranes showed a large expression of [125I]Sar1,Ile8-AII binding sites in the atria of neonatal Wistar Kyoto rats which were predominantly of the AT2 subtype. Atrial and ventricular cells, isolated from neonatal rat hearts and maintained for 3 days in culture demonstrated primarily AT1 binding sites. Stimulation of cultured atrial cells with AII resulted in an increase in inositol phosphate turnover and in intracellular calcium. The latter action was completely abolished by Losartan. Finally, in atria isolated from 2-month-old rats, AII produced a 17-19% increase in contractile force that was completely abolished by Losartan but not by PD 123319, thus indicating the presence of functional AT1 receptors.
在大鼠心脏的不同制剂中评估了 AII 受体亚型的分布和功能。放射自显影实验以及对分离膜进行的结合实验表明，新生 Wistar Kyoto 大鼠心房中 [125I]Sar1,Ile8-AII 结合位点大量表达，这些位点主要为 AT2 亚型。从新生大鼠心脏分离并在培养中维持 3 天的心房和心室细胞主要显示出 AT1 结合位点。用 AII 刺激培养的心房细胞会导致肌醇磷酸周转率和细胞内钙增加。后一种作用被氯沙坦完全消除。最后，在从 2 月龄大鼠分离的心房中，AII 使收缩力增加了 17 - 19%，这一作用被氯沙坦完全消除，但未被 PD 123319 消除，因此表明存在功能性 AT1 受体。
