Effects of insulin replacement on ejaculatory dysfunction in streptozotocin‐induced diabetic rats

Abstract

Objectives:To investigate the effects of insulin replacement on ejaculatory dysfunction in streptozotocin (STZ)-induced diabetic rats. Methods: Rats were divided into three groups: (i) STZ-treated group; (ii) STZ-treated + insulin replacement (5 and 2 international units [IU]) group; and (iii) control group. The ejaculatory function in rats was evaluated using the spontaneous seminal emission (SSE) test. The amount of seminal vesicle fluid (SVF) stored in seminal vesicle was measured after the SSE test. Blood glucose was measured using a simplified blood glucose meter. Results: In the SSE test, the ejaculatory capacity in STZ-induced diabetic rats deteriorated with time after the onset of diabetes, and the incidence of SSE and the amount of ejaculated seminal material (SM) were significantly decreased from 5 weeks after STZ administration. Likewise, the amount of SVF was also significantly decreased in a time-dependent manner. One week after STZ administration when ejaculatory capacity had not yet diminished , insulin replacement (for 4 weeks) completely prevented the decrease in frequency of SSE, the amount of SM and SVF. However, insulin replacement after the dysfunction had occurred (5 or 15 weeks after STZ administration) did not allow all parameters for ejaculatory function to be restored to the levels of the control group. Conclusion: This study demonstrates that at an early stage following the onset of diabetes, insulin replacement can prevent ejaculatory dysfunction in STZ-induced diabetic rats, but once the dysfunction occurs, treatment with insulin alone does not restore the ejaculatory capacity to normal levels. In addition, this study suggests that the loss of seminal emission that results from a decrease in SVF may be involved in the mechanism of ejaculatory dysfunction in diabetic rats.

Antidiabetic therapies and male reproductive function: where do we stand?

“…Although some studies have reported beneficial effects of insulin treatment on some aspects of sexual function such as copulatory behavior and ejaculation (Steger & Kienast 1990, Yonezawa et al 2009), few are the reports regarding the effects of insulin on erectile dysfunction (ED). Yet, this process also seems to be prone to the action of insulin.…”

“…Studies in diabetic individuals or in diabetic conditions, provided important insights concerning the importance of insulin (its absence or excess) to the male reproductive system, with several studies reporting that the reproductive changes found in diabetic individuals could be reverted or attenuated by insulin treatment (Seethalakshmi et al 1987, Gondos & Bevier 1995, Ikeda et al 2000, Yamanaka et al 2003, Kim & Moley 2008, Singh et al 2009, Yonezawa et al 2009, Schoeller et al 2012a.…”

“…The authors suggested that insulin is likely to have a role on the processes behind seminal emission and/or excretion in rats (Yonezawa et al 2009). Overall, acting at all the levels of the male reproductive system and reverting/attenuating the reproductive alterations found on diabetic individuals, insulin has an unquestionable role on male fertility.…”

Improvement of Hyperglycemia and Sexual Dysfunction in Diabetic Female Rats by an Artificial Endocrine Pancreas Developed from Mouse .BETA. Cells

“…Key words: bioartificial endocrine pancreas, diabetic rats, streptozotocin Japan Diabetes is one of the causes of sexual dysfunction, inducing neuroendocrine dysfunction [11,13,19,21] and apoplexy [2] based on hyperglycemia and insulin insufficiency. Rats are usually used as a diabetic animal models as diabetes can be induced by streptozotocin (STZ) for observations of sexual behavior [18,21,22,23]. Both men and women can contract type 1 and 2 diabetes.…”

“…Rats are usually used as a diabetic animal models as diabetes can be induced by streptozotocin (STZ) for observations of sexual behavior [18,21,22,23]. Both men and women can contract type 1 and 2 diabetes.…”