Expression Changes of the Phosphodiesterase 5 isoform in the Penis of Type 2 Diabetic Rat / 대한남성과학회지

ABSTRACT

PURPOSE: To investigate the tissue distribution of PDE5 isoforms in type 2 diabetic rat penile tissues. MATERIALS AND METHODS: We prepared ten male Otsuka Long-Evans Tokushima Fatty (OLETF) rats, which develop NIDDM naturally, and ten control male Long-Evans Tokushima Fatty (LETO) rats. An oral glucose tolerance test confirmed diabetes development in OLETF rats at 26 weeks. At 42 weeks, we checked serum glucose, testosterone, triglyceride, insulin, and adiponectin before sacrifice. We performed semi-quantitative multiplex RT-PCR for rat PDE5, PDE5A1, and PDE5A2. Immunohistochemistry was performed using mouse monoclonal anti-cGB-PDE5 and anti-smooth muscle alpha-actin. RESULTS: OLETF rats were significantly more hyperglycemic, hypogonadal, hyperinsulinemic, hypercholesterolemic, hypertriglycemic, and had lower adiponectin levels than LETO rats. Levels of PDE5 mRNA were decreased in OLETF rats, but there were no changes in PDE5A1 or PDE5A2 mRNA levels. CONCLUSION: Diabetes may contribute to decreased expression of PDE5 mRNA, but not PDE5A1 or PDE5A2, in rat penile tissue. Furthermore, serum free testosterone was decreased in diabetic rats. PDE5 has an important role in the development of diabetic erectile dysfunction, but it is not clear whether PDE5A1 and PDE5A2 gene have specific roles.