血红素氧合酶2在慢性肾衰大鼠阴茎海绵体中的表达

目的:检测血红素氧合酶2(HO-2)在慢性肾衰(CRF)大鼠阴茎海绵体中的变化,探讨HO-2在阴茎勃起过程中的作用及与睾酮的关系。方法:采用10周龄雄性SD大鼠行5/6肾切除术构建CRF模型成功后,测定对照组(CTL组,n=15)、CRF组(n=15)平均颈动脉压(MAP)及海绵体内压最大值(ICPmax)、血清睾酮,并检测阴茎海绵体中eNOS、nNOS、HO-2的表达。结果:CRF组在3V、5V电刺激海绵体神经后ICPmax/MAP(0.121±0.084,0.135±0.088)均显著低于对照组(0.263±0.147,0.244±0.089,P<0.01),CRF组血清睾酮浓度[(1.190±0.946)nmol/L]显著低于对照组[(7.800±5.001)nmol/L,P<0.01],CRF组海绵体中nNOS、eNOS表达低于对照组,CRF组海绵体中HO-2表达(0.510±0.397)显著低于对照组(2.672±1.720,P<0.01),海绵体中HO-2表达下降与血清睾酮下降存在相关性(r=0.902,P<0.01)。结论:CRF组大鼠阴茎海绵体中nNOS、eNOS、HO-2、血清睾酮水平降低等可能是CRF并发勃起功能障碍机制之一。

Correlation of HO-2 Expression in the Corpus Cavernosum with Erectile Disfunction in Rats with Chronic Renal Failure

OBJECTIVE: To detect the expression of HO-2 in the corpus cavernosum of rats with chronic renal failure (CRF) , and investigate the role of HO-2 in penile erection and its association with testosterone. METHODS: Fifteen 10-week-old SD rats underwent 5/6 kidney removal for the establishment of CRF models, and another 15 included as controls. Twelve weeks later, both the two groups of animals were subjected to electrostimulation of the cavernous nerve for the detection of intracavernosal pressure (ICP) and mean arterial pressure (MAP), and the protein contents of HO-2, nNOS and eNOS in the penile tissues were determined by Western blot and immunohistochemical analysis. RESUTLS: The ICPmax/MAP after 3 V and 5 V stimulation of the cavernous nerve was (0.121 +/- 0.084) and (0.135 +/- 0.088), the serum testosterone level was (1.190 +/- 0.946) nmol/L, and the expression of HO-2 was (0.510 +/- 0.397) in the CRF group, all significantly lower than in the control rats, which were (0.263 +/- 0.147 and 0.244 +/- 0.089), (7.800 +/- 5.001) nmol/L (P<0.01) and (2.672 +/- 1.720, P<0.01), respectively. There was a correlation between the decrease of HO-2 expression and the reduction of serum testosterone (r = 0.902, P < 0.01). CONCLUSION: The lowered level of serum testosterone and decreased contents of HO-2, eNOS and nNOS may play a role in CRF-induced ED.