低氧分压对大鼠勃起功能的影响

The effect of lower partial pressure of oxygen on erectile function of rats

目的探讨低氧分压对大鼠勃起功能障碍(ED)的影响。方法48只成年白色雄性SD大鼠随机分为对照组和实验组,每组按照实验时间(2周、6周、10周)分为3个亚组,每个亚组8只。实验组置于密闭低氧舱中饲养,对照组在正常环境中饲养,其他条件相同。分别观察其勃起功能,采用免疫组化SP法检测神经源性一氧化氮合成酶(nNOS)阳性神经纤维的数量、内皮源性一氧化氮合成酶(eNOS)的表达。结果实验组与对照组比较:(1)大鼠勃起次数明显降低(P<0.001);(2)nNOS阳性神经纤维数量、eNOS蛋白的表达均有显著性差异(P<0.01)。实验组间比较:勃起次数6周组明显低于2周组,10周组稍高于6周组;nNOS阳性神经纤维数量有显著性差异(P<0.01);eNOS的表达6周组最低,10周组有所回升。结论低氧分压致大鼠勃起功能受损和nNOS、eNOS的表达下降。nNOS染色阳性神经纤维数量的减少、eNOS表达的下降,可能是低氧分压环境中大鼠ED发生的原因之一。

Objective To investigate the effect of low partial pressure of oxygen on erectile function of rats. Methods Forty-eight two-month-old male Sprague-Dawley rats were divided into control group（24） and test group（24）. Each group was divided into 3 subgroups according to the time being exposed to hypoxia, each subgroup was 8. Test group was made into a rat model of erectile dysfunction by being exposed to lower partial pressure of oxygen. Control group was only exposed to air. Each subgroup was sacrificed for detecting nNOS-positive nerve fibers using strepavidin peroxidase immunohistochemistry techniques（SP method）, eNOS and histopathological changes in corpus cavernosum after erectile function test at planned time. Results （1） Significant difference exists in erectile frequency among test subgroups via paired-sample T test （P〈0.001）; （2） It was also of significant difference in the number of nNOS-positive nerve fibers and eNOS expression between test group and control group （P〈0.01）. Conelusion The erectile function and number of nNOS-positive nerve fibers in test group are dramatically affected by hypoxia. The decreasing of nNOS-positive nerve fibers and eNOS expression may be one of the mechanisms underlying erectile dysfunction after hypoxia.