HHcy大鼠tHcy与阴茎海绵体内NOS和H2S的相关性研究

摘要

目的：探讨甜菜碱（Betaine, Bet）对高同型半胱氨酸血症（HHcy）大鼠血浆总同型半胱氨酸（tHcy）及阴茎海绵体内一氧化氮合酶（NOS）、硫化氢（H2S）及勃起功能的影响。方法选用Wistar雄性大鼠45只，随机选出10只为对照组（A）。其余用3%蛋氨酸喂养，造模成功后的30只，随机分为：高同型半胱氨酸组（B）、盐酸甜菜碱治疗组（C）、叶酸、维生素B12治疗组（D）。A组给予正常饲料；B组3%蛋氨酸喂养。C组、D组，在喂养3%蛋氨酸的同时，分别给予Bet和叶酸、维生素B12灌胃。4周后，进行APO实验、大鼠阴茎海绵体内压（ICP）的测定、检测tHcy浓度及阴茎海绵体内NOS活性及H2S浓度。结果与A组比较，B组tHcy升高、阴茎海绵体内NOS活性及H2S浓度降低，ICP压力减低，勃起次数减少，有差异性，具统计学意义（P＜0.05）。C、D组与B组比较，tHcy降低、阴茎海绵体内NOS活性及H2S浓度增高，ICP压力增高，勃起次数增多（P＜0.05），同型半胱氨酸（Hcy）与NOS（rA=-0.857、rB=-0.976、rC=-0.903、rD=-0.847）和H2S（rA=-0.857、rB=-0.976、rC=-0.903、rD=-0.847）均成负性相关。C组与D组比较，tHcy降低、阴茎海绵体内NOS活性及H2S浓度升高，ICP压力增高，勃起次数增加，差异具统计学意义（P＜0.05）。结论 tHcy升高影响阴茎海绵体内NOS活性及H2S浓度的降低是引发勃起功能障碍（Erectile dysfunction ，ED）的机制之一。Bet是治疗HHcy所致ED的有效药物之一。%Objective To study the effects of Bet on erectile function by total homocysteine, NOS and endogenous H2S in penile corpus cavernosum of hyperhomocystinemia rats. Methods Forty-five Wistar male rates were included in the study. Ten of them were randomly selected as the control group (group A ; n=10) and were normally fed. To develop HHcy rats, other rats were fed with 3% methionine diet, then 30 rats of them were randomly divided into three groups as follows:HHcy rats group (group B, n=10), Betaine treated group (group C, n=10) and folic acid and vitamin B12 treated group (group D, n= 10). Four weeks later, ICP were examined, and the levels of the total plasma homocysteine were measured using cycle enzyme, additionally, NOS activity and H2S concentration was examined in penile homogenate. Results Compared with that of group A, the level of plasma tHcy significantly was increased in group B, but the NOS activity and H2S concentration in the penile cavernous tissue, the erection and ICP of rats were decreased significantly (P<0.05). Compared with that of group B, the level of plasma tHcy was significantly decreased in group C and group D, but the NOS activity, H2S concentration in the penile cavernous tissue, the erection and ICP of rats were significant increased (P<0.05), moreover, tHcy was negatively correlated with NOS activity (rA= -0.857, rB= -0.976, rC= - 0.903, rD= -0.847) and H2S concentrations (rA=-0.857, rB= -0.976, rC= -0.903, rD= -0.847), respectively. Compared with that of group D, the level of plasma tHcy in group C significantly decreased, whereas, the NOS activity, H2S concentrations in the penile cavernous tissue, the erection and ICP of rats were also decreased (P<0.05). Conclusion High level of plasma tHcy, and low NOS activity and H2S level in the penile corpus cavernous may result in the ocurrence of ED. Betaine may be an effective agent that improves the erectile dysfunction.