高雌激素血症对雌性心肌梗塞大鼠心肌舒缩性能的影响

The effect of hyperestrogenemia on myocardial contractility and relaxation in myocardial infarction observed in female rats

本文研究了高雌激素血症对雌性心肌梗塞(MI)大鼠心肌舒缩性能的影响。结果:(1)MI组血浆雌二醇(E_2)先略升高而后降低,雌二醇处理MI组(MIE_2)血浆雌二醇明显升高。(2)MIE_2组心肌纤维直径比对照假手术组(CS)及MI组显著增大(10.65±0.59 VS 7.65±0.40及10.15±0.54gm,P<0.001,<0.02)。(3)两MI组的LVSP、±dp/dt max均显著降低,T-值明显延长,尤以MIE_2组更为显著(10.5±4.1 VS 6.2±4.6ms,P<0.02)。(4)两MI组动脉压显著降低,HR减慢,LVET延长;在9天观测点,MIE_2组的HR仍较MI组显著减慢、LVET明显延长。提示高雌激素血症可使雌性心肌梗塞大鼠心肌舒缩性能降低。

The effect of hyperestrogenemia induced by intramuscular injectied estradiol (E_2) on myocardial contractility and relaxation was observed in female rats with myocardial infarction (MI). The results showed that: (1) In MI group, the plasma estradiol level increased slyghtly and then droped, while the level of estradiol increased markedly in rats treated by E_2 in MI (MIE_2) group. (2) Diameter of myofibril in MIE_2 grows more than that of control sham operation(CS) and MI (10.65±0.59 VS 7.65±0.40 and 10.15±0.54μm, P<0.001, <0.02). (3)LVSP, dp/dt max droped markedly in both MI groups; T-value extended obviously, this was especially marked in MIE_2 group (10.5+4.1 VS 6.2+4.6 ms, P<0.02). (4) Blood pressure droped, heart rate slowed down, LVET extended in both MI groups and these changes were more ob vious in MIE_2 group, there still was statistics difference between two groups at the 9th day of observation. The results indicate that the decrease of myocardial contractility and relaxation could be made by hyperestrogenemia.