糖尿病性勃起功能障碍大鼠模型的建立及阴茎海绵体组织nNOS的变化

Establishment of Diabetic Rats Model with Erectile Dysfunction and Change of nNOS in Corpus Cavernosum

目的研究糖尿病性勃起功能障碍(ED)大鼠模型的建立及阴茎海绵体组织nNOS表达活性的变化。方法1.24只SPF级SD雄性大鼠,随机分为4组,按不同处理因素给大鼠腹腔注射链脲佐菌素(STZ),分别记录4d、1周、2周、3周的体质量、阿朴吗啡(APO)诱导阴茎的勃起次数及空腹血糖值。2.40只SPF级SD雄性大鼠,先随机分为两组,一组注射STZ后观察7周,另一组注射STZ后观察4周,按照成模标准,将每一处理组又分为对照组、成糖尿病性勃起功能障碍模型组、成糖尿病性非勃起功能障碍组、未成模组。采用免疫组化SP法检测大鼠阴茎组织中nNOS的表达,利用彩色图文分析系统,测量随机每高倍镜视野下累积光密度(IOD),以IOD值反映组织切片中nNOS表达程度。结果1.体质量及空腹血糖在四个不同时间点和不同处理组间均有显著性差异(P均<0.001),注射STZ60mg/kg组体质量较轻、血糖较高。APO诱导阴茎勃起次数在四个不同组间有显著性差异(F=2.831,P=0.046),注射STZ60mg/kg组应用APO后阴茎未勃起的例数较多。2.注射STZ后4周与注射STZ后7周处理组各不同组别间IOD存在显著性差异(F=3.864,P=0.020),糖尿病性勃起功能障碍组IOD均小于对照组、糖尿病非勃起功能障碍组及未成模组(P<0.05)。结论1.大鼠注射STZ后两周,血糖>7.2mmol/L及APO诱导阴茎未勃起的,可认为是糖尿病性勃起功能障碍模型(DM&ED);2.糖尿病ED大鼠阴茎海绵体组织中nNOS表达量明显减少,这可能是糖尿病性勃起功能障碍的发病机理之一。

Objective To investigate the ideal diabetic rats model with erectile dysfunction and the nNOS change in corpus cavernosum. Methods 1.24 male SD rats were randomly divided into four groups（control group, STZ 40 mg/kg group, STZ 60 mg/kg group, Buffer group）, 6 rats in each group. And all rats were observed four days, one week, two weeks and three weeks after STZ injection. The mass, erectile frequency induced by apomorphine and fasting blood glucose should be recorded. 2.40 rats were first divided into two groups randomly： 4 week group and 7 week group, diabetes mellitus rats model with erectile dysfunction were made through streptozotocin （STZ） injection according to the model standard, and then 4 week group and 7 week group were divided into four groups, which were control group （5 rats each, without STZ injection）, diabetes mellitus rats with erectile dysfunction group （DM ＆ ED group）, diabetes mellitus rats without erectile dysfunction group （DM group） and rats without diabetes mellitus and erectile dysfunction group after STZ injection（none group）. Im- munohistochemical staining method and color image analysis and IOD were used to observe expression of nNOS in rats corpus cavemosum of different groups. Results 1. There are significant differences in mass and fasting food glucose among groups of different test time and different dose of STZ injection （P 〈 0.001）. Significant difference exists in erectile frequency induced by apomorphine among groups of different dose of STZ injection（F =2.831, P =0.046）. 2. There is significant difference in nNOS expression （IOD） between DM ＆ ED group and other three groups （F=3.864, P =0.020） in the 4 week group and 7 week group. Expression of nNOS（IOD） in corpus cavemosum in DM ＆ ED group is the lowest in all four groups （P 〈0.05）. Conclusions 1. Diabetic rats model with erectile dysfunction can be considered if fasting serum glucose exceeds 7.2 mmol/L and penile erection do not appear after APO injection. 2.The expression ofnNOS has a descent tendency in diabetic rats with erectile dysfunction.The decreasing ofnNOS may be one of the mechanisms of diabetic erectile dysfunction.