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.
Results: 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.