血栓素B2：具有涉及β-肾上腺素能受体和钠钾ATP酶活性的心脏刺激作用。

TXB2: cardiostimulant effect that involves beta-adrenoceptor and Na+ + K+-ATPase activity.

作者信息

Pascual J, Sterin-Borda L, Wald M, Borda E S

机构信息

Cefaprin--Conicet, Buenos Aires, Argentina.

出版信息

Prostaglandins Leukot Essent Fatty Acids. 1988 Jul;33(1):53-9. doi: 10.1016/0952-3278(88)90123-8.

DOI:10.1016/0952-3278(88)90123-8

PMID:2847200

Abstract

The biological properties of Thromboxane B2 (TXB2) on isolated rat heart were studied. Its actions were compared with U-46619 a Thromboxane A2 mimetic compound and with isoproterenol. TXB2 induced a concentration-dependent increase in contractility, that was non-competitively antagonized by propranolol. In addition TXB2 inhibited Na+ + K+-ATPase activity at the same concentrations that influenced the mechanical activity. Inhibition of beta-adrenoceptors efficiently blocked the inhibitory action of TXB2 upon Na+ + K+-ATPase-activity. Isoproterenol simulated the positive inotropic effect and the inhibitory action of TXB2 on Na+ + K+-ATPase-activity. In contrast, U-46619 did not alter the basal dF/dt, neither the enzyme activity. The foregoing results suggest that TXB2 resembles the biological effect of catecholamines-inducing stimulation of myocardial contractility and inhibition of Na+ + K+-ATPase activity.

摘要

研究了血栓素B2（TXB2）对离体大鼠心脏的生物学特性。将其作用与血栓素A2模拟化合物U-46619以及异丙肾上腺素进行了比较。TXB2诱导收缩力呈浓度依赖性增加，普萘洛尔对其有非竞争性拮抗作用。此外，TXB2在影响机械活性的相同浓度下抑制Na+ + K+-ATP酶活性。β-肾上腺素能受体的抑制有效地阻断了TXB2对Na+ + K+-ATP酶活性的抑制作用。异丙肾上腺素模拟了TXB2的正性肌力作用及其对Na+ + K+-ATP酶活性的抑制作用。相比之下，U-46619既不改变基础dF/dt，也不改变酶活性。上述结果表明，TXB2类似于儿茶酚胺的生物学效应，可诱导心肌收缩力增强并抑制Na+ + K+-ATP酶活性。