[Impact of aging on the secretion of insulin-like growth factor-1 in the corpus cavernosum smooth muscle cells of rats in vitro].

OBJECTIVE: To observe the secretion of insulin-like growth factor-1 (IGF-1) in corpus cavernosum smooth muscle cells (CCSMCs) in rats of different ages and explore the possible relationship of IGF-1 with aging-related erectile dysfunction (ED). METHODS: We primarily cultured CCSMCs of rats aged 4, 12 and 24 months, and identified them by immunohistochemistry. We quantitatively cultured the CCSMCs in 6-well culture plates, determined the levels of IGF-1 secreted from the CCSMCs by enzyme immunoassay (EIA) and analyzed the effect of age on the IGF-1 level. RESULTS: CCSMCs were successfully cultured in vitro. The level of IGF-1 secreted from the CCSMCs was decreased with the increase of age, with 7.1 ng/10(5) cells in the 4-month-old group, 2.2 ng/10(5) cells in the 12-month group, and 1.9 ng/10(5) cells in the 24-month group, with statistically significant differences among the three groups (P < 0.01). CONCLUSION: The secretion of IGF-1 is reduced with the increase of age, and the decreased expression of IGF-1 might be associated with aging-related ED.