雌二醇对去卵巢大鼠血清一氧化氮的影响

THE EFFECTS OF ESTRADIOL (E_2) ON SERUM NITRIC OXIDE (NO) LEVEL OF OVARIECTIOMIZED RATS

目的：观察雌二醇对去卵巢大鼠血清一氧化氮的影响。方法：采用去卵巢大鼠模型，通过肌注苯甲酸雌二醇2周，测量不同雌激素状态下大鼠血清一氧化氮（NO）的浓度，用镉还原法测NO2／NO3的量来反映NO浓度。结果：切除卵巢三周后，血浆雌二醇浓度显著下降（P＜0，05），NO浓度轻度下降，但无统计学差异（P＞0．05），当补充大剂量雌二醇后，发现去卵巢大鼠血清NO显著升高（P＜0．05），血清E2水平也极显著升高（P＜0．01）。结论：雌二醇可促进去卵巢大鼠血清NO水平增加，这可能是雌激素抑制动脉粥样硬化和降低女性绝经后冠心病发病危险的重要机制之一。

Objective: The aims of the study were to investigate the effect of E_2 on serum NO level of ovariectomized rats and to clarify the mechanism of the cardiovascular protective effects of E2. Methods: Wistar rats were divided into three groups: Ovariectomized(OVX), ovariectomized and estradiol replacement(OVX + E2 )and sham. Having been hred for three weeks, the rats were killed for collecting blood, then serum NO_2^- /NO_3~ level was measured by using kinetic cadmium - reduction methed. Results: Compared with Shain, ferum NO level in OVX was moderately lowered (P < 0.05), but serum NO level in OVX + E2 was increased more significantly than that of sham or OVX (P < 0. 05). Conclusions: The results suggest that E2 can stimulate the production of NO in rats, which might be involved in the antiatherogenic action of estrogen.