两种单宁的强心作用。
Cardiotonic action of two tannins.
作者信息
BROADBENT J L
出版信息
Br J Pharmacol Chemother. 1962 Feb;18(1):167-74. doi: 10.1111/j.1476-5381.1962.tb01160.x.
A tannin isolated from Paullinia pinnata Linn., and tannic acid, have cardiotonic actions on the isolated perfused frog heart. Paullinia tannin is more firmly "fixed" than tannic acid. Tannin solutions contain peroxide, but the cardiotonic action is not dependent on this, since drugs believed to prevent peroxide formation, and sodium pyruvate which destroys peroxides, do not prevent the cardiotonic action. Maximal stimulation by tannin greatly reduces subsequent stimulation by ouabain. If calcium is omitted from the Ringer solution tannins cannot stimulate the heart. In this respect they differ from ouabain. However, the ouabain stimulation can be prevented by prior perfusion with tannin. It is suggested that the antagonism between tannin and ouabain is due to the former preventing ouabain from reaching its receptor sites, and that tannin stimulation is dependent on the formation of a calcium-tannin complex at the heart surface. In the isolated perfused mammalian heart preparation tannins increase diastolic tonus and coronary flow.
从羽叶泡林藤中分离出的一种单宁以及鞣酸，对离体灌流的蛙心有强心作用。泡林藤单宁比鞣酸更牢固地“固定”。单宁溶液含有过氧化物，但强心作用并不依赖于此，因为据信能防止过氧化物形成的药物以及能破坏过氧化物的丙酮酸钠并不能阻止强心作用。单宁的最大刺激作用会极大地降低随后哇巴因的刺激作用。如果林格氏溶液中不含钙，单宁就不能刺激心脏。在这方面它们与哇巴因不同。然而，哇巴因的刺激作用可通过先用单宁灌流来防止。有人认为单宁与哇巴因之间的拮抗作用是由于前者阻止哇巴因到达其受体部位，并且单宁的刺激作用依赖于在心脏表面形成钙 - 单宁复合物。在离体灌流的哺乳动物心脏制备中，单宁会增加舒张期张力和冠状动脉血流量。
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