Determination of kisspeptin immunreactivity in testes of rats with streptozotocin-induced diabetes

Aim: Diabetes Mellitus, is a metabolic disorder which is generally characterized with hyperglycemia that is developed due to corruption in insulin secretion or effectiveness an it affects reproductive health negatively. Hypothalamus-pituitary-gonadal axis work together coordinated and have a role in organizing reproductive function. Neuropeptides called kisspeptin which are synthesized by hypothalamic neurons are which axis and regulate transition to puberty and fertility. In this study we have aimed to find out how diabetes mellitus affects testicular tissue and the kisspeptin immunoreactivity in this tissue according to time. Materials and Methods: In this study, 48 8-week-old Spraqua Dawley male rats have been used. Rats have been classified as Group I, Group II, Group III. Diabetic rats have been classified as 3-days-old, 1-week, 2-week, and 4- week-old. At the end of the experiment, rats have been decapitated under anesthetized. Blood samples have been taken from subjects for measuring serum testosterone level and testicular tissues for histopathological examining. Paraffin blocks have been prepared by routine tissue preparation method. The tissue blocks were sectioned at a thickness of 5 µm to perform histochemical and immunohistochemical staining. Results: At the end of the experiment, in diabetic group, we have observed a decrease in weight and serum testosterone level among the rats meaningfully especially after 1 weeks. Diabetes Mellitus has been existed on 3 days and on this day the affection of tissue has been on a minimal level with the increase of diabetes mellitus, we have observed degeneration in seminiferous tubules epithelium, interstitial edema and immature spermatogenic cells in some tubules lumens. Addition to these findings in 2-weeks-old and 4-weeks-old diabetic group, we have observed some atrophic tubules. In tissue sections which have been immunohistochemical stained, we have found out clear kisspeptin immunoreactivity in Leydig cells and spermatogenic cells in control, sham and 3-days-old diabetic groups. According to progress of diabet time, we have observed a clear reduction in intensity of spermatogenic cells kisspeptin immunreactivity. Conclusion: It has been tought that structural impairments in testis due to diabetes mellitus, with the reduction in kisspeptin immunoreactivity and serum testosterone level that in healthy conditions, regulation of testicular physiology and protection of structural integrity, kisspeptin and testosterone are molecules that work correlated with each other. Key words: Diabetes Mellitus, Kisspeptin, Rat, Testis.