Kakouris H, Eddie L W, Summers R J
Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Australia.
Lancet. 1992 May 2;339(8801):1076-8. doi: 10.1016/0140-6736(92)90665-p.
Relaxin is usually considered to be a hormone of pregnancy, but porcine relaxin has been shown to increase heart rate in rats. We investigated the cardiac effects of synthetic human gene-2 relaxin (hRlx-2) in vitro in isolated rat atria. Synthetic hRlx-2 produced concentration-dependent positive chronotropic effects in spontaneously beating right atria (EC50 [concentration required to produce 50% of the maximal response] = 0.09 [SE 0.03] nmol/l) and concentration-dependent positive inotropic effects in electrically driven left atria (EC50 = 0.31 [0.02] nmol/l). The potency of hRlx-2 is greater than that of endothelin, angiotensin II, and (-)-isoprenaline in isolated rat atria. Relaxin has powerful chronotropic and inotropic effects on the heart that are probably mediated through a direct action on relaxin receptors.
松弛素通常被认为是一种妊娠激素，但已证明猪松弛素可使大鼠心率增加。我们在体外对离体大鼠心房研究了合成人基因 -2 松弛素（hRlx -2）的心脏效应。合成的 hRlx -2 在自发性搏动的右心房产生浓度依赖性正性变时作用（EC50 [产生最大反应 50%所需的浓度] = 0.09 [标准误 0.03] nmol/L），在电驱动的左心房产生浓度依赖性正性变力作用（EC50 = 0.31 [0.02] nmol/L）。在离体大鼠心房中，hRlx -2 的效力大于内皮素、血管紧张素 II 和（-）-异丙肾上腺素。松弛素对心脏具有强大的变时和变力作用，这可能是通过对松弛素受体的直接作用介导的。
