Gaide M S, Fitterman W S, Wiggins J R, Myerburg R J, Cameron J S, Bassett A L
J Cardiovasc Pharmacol. 1983 Mar-Apr;5(2):335-40. doi: 10.1097/00005344-198303000-00028.
The effects of amrinone (5.3 X 10(-4) M) on isometric contraction and K+-induced contracture force of right ventricular muscle isolated from normal cats (n = 6) and cats in right ventricular failure (RVF, n = 6), 3-14 days after partial pulmonary artery ligation, were studied. Peak isometric contractile force (Po) and maximal rate of force development (dP/dt) of RVF muscles (1.38 +/- 0.21 g/mm2; means +/- SEM, and 11 +/- 1 g/s/mm2, respectively) were significantly lower than normal muscles (2.46 +/- 0.41 g/mm2, p less than 0.025, and 24 +/- 3 g/s/mm2, p less than 0.005, respectively). Duration of contraction (DC) was significantly longer in RVF muscles (442 +/- 32 ms) than in normal muscles (361 +/- 11 ms, p less than 0.025). Times to peak twitch force (TTP) and peak K+-induced contracture force (Pc) of RVF and normal muscles were not different. Amrinone increased Po and dP/dt significantly in normal muscles (+78 +/- 24%; means +/- SEM; p less than 0.01, and +53 +/- 17%, p less than 0.025, respectively), but not RVF muscles (+11 +/- 16% and +8 +/- 19%, respectively). TTP and DC of normal muscle were unchanged by amrinone, whereas TTP was unchanged while DC was shortened (-12 +/- 3%, p less than 0.025) in RVF muscle. Amrinone relaxed Pc similarly and significantly in normal (-28 +/- 7%, p less than 0.005) and RVF (-26 +/- 4%, p less than 0.025) muscles. These results suggest that part of amrinone's salutary action in the failing heart occurs through modification of myocardial relaxation.
研究了氨力农（5.3×10⁻⁴M）对正常猫（n = 6）和部分肺动脉结扎3 - 14天后右心室衰竭（RVF，n = 6）猫所分离的右心室肌肉等长收缩及钾离子诱导的挛缩力的影响。RVF肌肉的等长收缩峰值力（Po）和最大力发展速率（dP/dt）（分别为1.38±0.21 g/mm²；平均值±标准误，以及11±1 g/s/mm²）显著低于正常肌肉（分别为2.46±0.41 g/mm²，p＜0.025，以及24±3 g/s/mm²，p＜0.005）。RVF肌肉的收缩持续时间（DC）（442±32 ms）显著长于正常肌肉（361±11 ms，p＜0.025）。RVF肌肉和正常肌肉达到峰值抽搐力（TTP）及峰值钾离子诱导挛缩力（Pc）的时间无差异。氨力农使正常肌肉的Po和dP/dt显著增加（分别增加+78±24%；平均值±标准误；p＜0.01，以及+53±17%，p＜0.025），但对RVF肌肉无此作用（分别增加+11±16%和+8±19%）。氨力农对正常肌肉的TTP和DC无影响，而对RVF肌肉，TTP不变，DC缩短（-12±3%，p＜0.025）。氨力农使正常肌肉和RVF肌肉的Pc同样显著降低（分别降低-28±7%，p＜0.005，以及-26±4%，p＜0.025）。这些结果提示，氨力农在衰竭心脏中的部分有益作用是通过改善心肌舒张实现的。
