Kianoosh Gholami - Student Research Committee, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran
Beheshteh Abouhamzeh - Department of Anatomical Sciences, Faculty of Medicine, AJA University Of Medical Sciences, Tehran, Iran
Esmaeil Samizadeh - Imam Reza Hospital Pathology Lab, AJA University Of Medical Sciences, Tehran, Iran

Background and Objective: Stress occurs in response to the effects of external harmful factors and its stimulators or the causative position that has a significant epidemic in today’s world. On the other hand it can be an important factor in creating body organs’ disorders such as reproductive system disorders. This study focused on the effects of chronic unpredictable stress on serum testostrone level, tissue PLZF and histopathological changes of testicular tissue. Materials and methods: 32 Wistar rats were divided into 4 groups (G1: young control; G2: young stress; G3: old control; G4: old stress). Stress groups underwent chronic unpredictable stress. After 8 weeks, serum testostrone was measured by ELISA test, tissue PLZF changes were studied by IHC and histological changes of testicular tissue were studied by H&E staining. Data were evaluated by two-way ANOVA followed by Bonferroni test for multiple comparisons. Findings: Serum testosterone levels were significantly lower in stress-exposed rats in comparison with control groups. Also, the PLZF level measured in testicular tissue of stress-exposed groups was in lower range. Histological results showed that the spermatogonial population in both stress groups was decreased and also sloughing in seminiferous tubules has been increased by aging. Conclusion: The results showed that unpredictable chronic stress reduces testosterone level and its production. And It also causes testicular tissue disorders in rats that will have adverse effects on fertility..

chronic stress, testis, testosterone, PLZF