Objective: To investigate the effect of elastic fiber alterations in the tunica albuginea of the penis on erectile function of diabetic rats.
Methods: Streptozotocin (STZ) injection was adopted to produce rat models of diabetes mellitus and erectile dysfunction. Forty rats were randomized equally into two groups according to the time after streptozotocin (STZ) injection, namely 4 week group and 7 week group. Each group was further divided into 4 subgroups, including a control group (n=5, without STZ injection), diabetic with erectile dysfunction group (DM and ED group), diabetic without erectile dysfunction group (DM group) and group with neither diabetes mellitus or erectile dysfunction after STZ injection (None group). Victoria blue/Ponceau red staining and color image analysis were used to observe the content of the elastic fibers in the tunica albuginea, which was quantified by means of integrated optical density (IOD) readings.
Result: Significant difference in the IOD was observed between different groups (F=10.433, P<0.001). The content of elastic fibers in the tunica albuginea was the lowest in DM and ED group among the 4 groups (P<0.05), and there was no significant difference between 7-week and 4 week groups (F=0.685, P=0.415), nor was any interaction observed (F=0.905, P=0.452).
Conclusions: Decreased elastic fibers in the tunica albuginea can result from diabetes mellitus. Elastic fibers in the tunica albuginea play an important role in the course of erection, and erectile dysfunction may result from decreased elastic fiber content.