Ma Y X, Yu S, Zhao H Y
Department of Internal Medicine, Tongji Hospital, Tongji Medical University, Wuhan.
J Tongji Med Univ. 1994;14(4):216-9. doi: 10.1007/BF02897671.
In a perfused isovolumetrically contracting rat heart model, the effects of isoprenaline (IPN) and phenylephrine (PE) on myocardial contraction and relaxation were investigated, and the influence of nifedipine on these effects was studied. Both IPN and PE increased the myocardial contraction and improved its relaxation, but some differences existed. Nifedipine (10 nmol/L) substantially inhibited the PE-mediated inotropic effect, but in case of IPN-mediated inotropic ones, it did not. It was assumed that there may be various types of slow channels, one was activated by IPN, and the other, by PE.
在一个灌注等容收缩大鼠心脏模型中，研究了异丙肾上腺素（IPN）和去氧肾上腺素（PE）对心肌收缩和舒张的影响，并研究了硝苯地平对这些影响的作用。IPN和PE均增加了心肌收缩并改善了其舒张，但存在一些差异。硝苯地平（10 nmol/L）显著抑制了PE介导的变力作用，但对于IPN介导的变力作用则没有。据推测，可能存在多种类型的慢通道，一种由IPN激活，另一种由PE激活。
