糖尿病勃起功能障碍大鼠血清睾酮的变化及意义

Role of decreased expression of serum testosterone in streptozotocin-induced diabetic rats

目的:探讨睾酮在糖尿病大鼠勃起功能障碍(ED)发生中的意义。方法:3月龄Wistar雄性大鼠18只(SPF级),随机分为正常对照和糖尿病组,每组9只,采用链脲佐菌素(STZ)建立糖尿病大鼠模型,3月后检测大鼠阴茎海绵体内压(ICP)和平均动脉压(MAP)以评价勃起功能,然后分别行ELISA法检测血清睾酮水平和阴茎海绵体组织中cGMP浓度的变化,Masson法检测阴茎海绵体平滑肌密度的变化。结果:糖尿病组大鼠海绵体内压为(58±11) mmHg,低于正常对照组(115±13) mmHg,差异有统计学意义(P<0. 05),同时糖尿病组大鼠的血清睾酮水平[(17. 45±2. 54) pmol/mL]较正常组[(338. 46±63. 80) pmol/mL]明显下降(P<0. 05);且我们还发现糖尿病组大鼠阴茎海绵体平滑肌密度和阴茎海绵体组织中cGMP浓度均明显下降,差异有统计学意义(P<0. 05)。结论:糖尿病大鼠血清睾酮水平明显下降,可能通过降低阴茎海绵体平滑肌的密度和大鼠阴茎海绵体组织中cGMP含量,从而在糖尿病ED的发生过程中发挥一定的作用。

Objective: To investigate the role of testosterone in diabetes mellitus with erectile dysfunction(ED) in rat’s model.Methods: Three-month-old male Wistar rats(n=18) were divided into nomal contorl group(n=9) and diabetes mellitus with erectile dysfunction group(n=9). The largest intracavernous pressure(ICP) was mesured after cavernous nerve electrostimulation. Serum levels of serum testosterone and the concentration of cGMP were measured by enzyme-linked immunosorbent assay(ELISA) respectively and the percent of corporal smooth muscle cells was detected by masson staining.Results: The largest ICP of diabetes mellitus with erectile dysfunction group was significantly lower than that of nomal control group, as(58±11) mmHg vs(115±13) mmHg(P<0. 05), and serum levels of testosterone of diabetes mellitus with erectile dysfunction group was obviously lower than that of nomal contorl group, as(17. 45± 2. 54) pmol/mL vs(338. 46± 63. 80) pmol/mL(P<0. 05). The nomal contorl group had higher percent of corporal smooth muscle cells than the diabetes mellitus with erectile dysfunction group(P<0. 05). The concentration of cGMP were significantly decreased in diabetes group as compared with normal control group(P<0. 05).Conclusion: During the development of ED in STZ-induced diabetic rats, the decline of testosterone levels may play an important role, maybe through decreasing the percent of corporal smooth muscle cells and cavernous cGMP levels.