Tsushima H, Mori M, Matsuda T
Jpn J Pharmacol. 1985 Nov;39(3):365-74. doi: 10.1254/jjp.39.365.
Effects of catecholamines microinjected into the supraoptic nucleus in the hypothalamus on urine outflow in rats which were loaded with water and anesthetized with ethanol were studied. L-Norepinephrine, L-epinephrine and L-isoproterenol induced potent antidiuresis, showing similar time courses to each other. The ED50 values for L-norepinephrine, L-epinephrine and L-isoproterenol were approx. 25, 20 and 5 nmol, respectively. The D-isomer of isoproterenol demonstrated no significant antidiuretic activity. The effect of L-norepinephrine was inhibited strongly by preinjection of alpha- and beta-adrenoceptor antagonists. The effect of DL-isoproterenol was inhibited strongly by beta-adrenoceptor antagonists, but not affected by alpha-adrenoceptor antagonist. Among the three catecholamines, only L-epinephrine induced a tachyphylaxis in the antidiuretic effect. Visceral functions other than urine outflow such as blood pressure, respiration rate, heart rate and rectal temperature were not significantly changed by microinjecting antidiuretic doses of the catecholamines. The results demonstrated that stimulation of alpha- and beta-adrenoceptors in the supraoptic nucleus induced a potent antidiuretic effect.
研究了向下丘脑视上核微量注射儿茶酚胺对水负荷并用乙醇麻醉的大鼠尿排出量的影响。左旋去甲肾上腺素、左旋肾上腺素和左旋异丙肾上腺素均引起强效抗利尿作用，它们的时间进程彼此相似。左旋去甲肾上腺素、左旋肾上腺素和左旋异丙肾上腺素的半数有效量（ED50）分别约为25、20和5纳摩尔。异丙肾上腺素的D-异构体未表现出明显的抗利尿活性。预先注射α和β肾上腺素能受体拮抗剂可强烈抑制左旋去甲肾上腺素的作用。DL-异丙肾上腺素的作用可被β肾上腺素能受体拮抗剂强烈抑制，但不受α肾上腺素能受体拮抗剂的影响。在这三种儿茶酚胺中，只有左旋肾上腺素在抗利尿作用中出现快速耐受性。注射抗利尿剂量的儿茶酚胺对除尿排出量以外的内脏功能如血压、呼吸频率、心率和直肠温度无明显影响。结果表明，刺激视上核中的α和β肾上腺素能受体可引起强效抗利尿作用。
