Analysis of the adrenergic receptors of pacemaker and myocardial cells.
Analysis of the adrenergic receptors of pacemaker and myocardial cells.
复制标题
起搏器和心肌细胞的肾上腺素能受体分析。
DOI：
10.1016/0014-2999(72)90261-0
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发表时间：
1972
影响因子：
5
通讯作者：
P. Urquilla
中科院分区：
文献类型：
--
作者：
J. Parr;P. Urquilla
在家兔心房自发搏动和电驱动下，测定了肾上腺素和苯肾上腺素的变时性和变力性剂量-反应曲线。曲线是在不存在和存在普萘洛尔（10− 7 M）或酚妥拉明（2 × 10− 6 M）的情况下获得的。普萘洛尔可拮抗肾上腺素和苯肾上腺素的变时作用和肾上腺素的变力作用。这种拮抗剂降低了对高剂量苯丙氨酸的正性肌力反应，但不改变低剂量的作用。酚妥拉明可拮抗低剂量苯丙氨酸的变力作用，而普萘洛尔对苯丙氨酸的变力作用无影响。酚妥拉明使肾上腺素的变力曲线右移2.5倍。α-和β-受体阻滞剂能拮抗肾上腺素能胺的变力作用，提示介导这些作用的受体具有两种受体共有的药理学特性。因此，双受体系统似乎在对肾上腺素能刺激产生变力性反应中起作用。此外，这些结果证实了β受体在肾上腺素能胺的心脏作用中所起的作用。
Chronotropic and inotropic dose-response curves for epinephrine and phenylephrine were determined in rabbit atria spontaneously beating and electrically-driven. The curves were obtained in the absence and in the presence of propranolol, 10−7M, or phentolamine, 2 × 10−6M. Propranolol antagonized the chronotropic effects of epinephrine and phenylephrine, and the inotropic effects of epinephrine. This antagonist reduced the inotropic responses to high doses of phenylephrine, but left unaltered the effects of low doses. Phentolamine antagonized the inotropic effects of low doses of phenylephrine which were unaffected by propranolol. The inotropic curve for epinephrine was shifted 2.5-fold to the right by phentolamine. In contrast, phentolamine did not modify the chronotropic responses to these amines.The ability of α- and β-blocking agents of antagonizing the inotropic effects of adrenergic amines suggest that the receptors mediating these effects possess pharmacological characteristics which are common to both types of receptors. Thus, a two-receptor system appears to operate in the production of inotropic responses to adrenergic stimuli. In addition, the results confirm the role played by β-receptors in the cardiac actions of adrenergic amines.