Effects of exercise on sexual function and central mechanism in the streptozotocin-induced diabetic rats

Diabetes mellitus is associated with the impairment of sexual function including desire and orgasmic dysfunction. Sexual dysfunction in the diabetes mellitus is due to a selective defect of the nitric oxide synthase (NOS) within paraventricular nucleus (PVN). c-Fos is an immediate ear-ly gene and c-Fos expression represents neuronal activity in response to various stimuli. In the present study, we investigated the effects of treadmill exercise on sexual behaviors and the expressions of NOS and c-Fos in the PVN were evaluated using streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by intraperitoneal injection of STZ. The rats in the treadmill exercise groups were made to run on a treadmill for 30 min once a day during 4 weeks. Male sexual behaviors were evaluated by recording the number of mounting, intromission, and ejaculation frequency. The present results revealed that treadmill exer-cise ameliorated sexual dysfunction in the STZ-induced diabetic rats. Treadmill exercise restored the contents of NOS and c-Fos in the PVN. The improving effect of treadmill exercise on sexual function can be considered as the neuronal activating effect of exercise through in-creasing expressions of NO and c-Fos.