雌激素对心肌肥大大鼠死亡率的影响

Effects of estrogen on the mortality of rats with myocardial hypertrophy

目的探讨雌激素对心肌肥大大鼠死亡率的影响。方法成年雌性SD大鼠随机分为6组。①假手术(Sham)组;②去卵巢(OVX)组:切除大鼠双侧卵巢;③去卵巢+雌激素补充(OVX+E2)组;④假手术+异丙肾上腺素(Sham+ISO)组;⑤去卵巢+异丙肾上腺素(OVX+ISO)组;⑥去卵巢+雌激素+异丙肾上腺素(OVX+E2+ISO)组。各组动物术后常规饲养。统计各组大鼠的死亡情况,观察心脏和胸主动脉苏木精一伊红染色。结果Sham+ISO组较Sham组心肌细胞体积增大,细胞问排列不整齐、间隙不清,细胞核变大、变圆;OVX组较Sham组血管周围组织炎症加重;OVX+E2组较OVX组周围组织炎症减轻;Sham+ISO组较Sham组炎症加重;OVX+E2+ISO组较OVX+E2组炎症也加重。术后第3、4、5周,OVX+E2组死亡率明显低于OVX组(P<0.01)。术后第6周,Sham+ISO组死亡率显著高于Sham组(P<0.05),OVX+ISO组死亡率明显高于OVX组(P<0.05),OVX+E2+ISO组死亡率明显高于OVX+E2组(P<0.01),而OVX+ISO组与OVX+E2+ISO组死亡率比较,差异元统计学意义(P>0.05)。结论注射异丙肾上腺素可导致大鼠心肌肥大。雌激素可减轻大鼠胸主动脉血管周围炎症浸润;异丙肾上腺素可加重大鼠胸主动脉血管周围炎症浸润。给予双侧去卵巢大鼠补充雌激素可降低其死亡率。注射异丙肾上腺素可增加各组大鼠的死亡率。雌激素对心肌肥大的大鼠死亡未见保护作用。

Objective To investigate the effect of estrogen on the mortality of rats with myocardial hypertrophy.Methods Healthy female adult SD rats were randomly divided into six groups:①a sham operation group (Sham),②an ovariectomized group.(OVX),③an ovariectomized +estrogen supplement group (OVX +E2),④a sham operation +isopro-terenol group (Sham +ISO),⑤an ovariectomized +isoproterenol group (OVX +ISO),and ⑥an ovariectomized +estro- gen +isoprenaline group (OVX +E2+ISO).Each group of animals was routinely fed and their mortality was calculated. The HE staining results of the cardiac and thoracic aorta were observed.Results Compared with the Sham group,the Sham +ISO group showed enlarged volumes of myocardial cells,irregularly arranged cells with unclear gap and larger and rounder nuclei.Compared with the Sham group,the OVX group presented aggravated inflammation in perivascular tissues,but tissue inflammation in the OVX +E2 and OVX groups was alleviated.The inflammatory became more aggregated in the Sham +ISO group than that in the Sham group.The inflammatory was also more aggregated in the OVX +E2 +ISO group than that in the OVX +E2 group.The mortality was significantly decreased in the OVX +E2 group,compared with that in the OVX group (P<0.01)on Weeks 3,4 and 5 after surgery.On Week 6 after surgery,a higher mortality was found in the Sham +ISO group than that in the Sham group (P <0.05 ),a higher mortality was found in the OVX +ISO group than that in the OVX group (P <0.05 ),and a higher mortality was found in the OVX +E2 +ISO group than that in the OVX + E2 group (P <0.01).There was no significant difference in mortality between the OVX +ISO and OVX +E2 +ISO groups (P >0.05).Conclusions Injection of ISO can lead to cardiac hypertrophy in rats.Estrogen can reduce inflammation a-round the thoracic aorta in rats.ISO can aggravate inflammatory infiltration of thoracic aorta in rats.Estrogen supplementation in ovariectomized female rats can reduce their postoperative mortality.ISO injection increases mortality in rats.Estro- gen has no protective effect on the death of myocardial hypertrophy rats.