ボピンドロール投与による高血圧自然発症ラット(SHR)の心筋α_1-及びβ-受容体の性状変化に関する研究 Effects of Chronic Administration of Bopindolol on the ^3H-Prazosin and ^3H-CGP12177 binding to α_1- and β-Adrenoceptors in the Heart of Spontaneously Hypertensive Rats(SHR)
We investigated the effects of chronic administration of bopindolol in the heart of spontaneously hypertensive rats (SHR) The values of Kd and Bmax of α<SUB>1</SUB> and β-adrenoceptors in the heart of SHR were calculated by Scatchard analysis used <SUP>3</SUP>H-prazosin and <SUP>3</SUP>H-CGP 12177 binding. In addition, their blood pressure was also determined and these effects of bopindolol were compared with those of other β-blockers. SHR were given bopindolol (1 mg/kg and 3 mg/kg), atenolol (50 mg/kg), propranolol (60 mg/kg) in drinking water during 12 weeks. The systolic blood pressure of SHR was lowered by chronic administration of bopindolol, dose-dependently observed. The chronic administration of bopindolol (3 mg/kg) to SHRs increased the Kd and Bmax values of the a lx-adrenoceptors (high affinity binding sites for <SUP>3</SUP>H-prazosin). On the other hand, the administration of bopindolol (1 mg/kg and 3 mg/kg) decreased the Bmax values of the β-adrenoceptor. These findings suggest that chronic administration of bopindolol had a beneficial effect on the blood pressure and had a dose-dependent effect on the α<SUB>1</SUB>- and β-adrenoceptors in the heart. These effects of bopindolol maybe involved in the inhibition of the development of hypertension.
日本薬理学雑誌 106, 177-181, 1995-09-01