How are testicular functions affected after morphine dependence and withdrawal in rats?

Objective:The effects of morphine addiction on testicular activity are significant.This study aimed to examine testicular contraction and tissue changes that may occur in the testicles of rats with experimentally induced morphine addiction.Method: Thirty-two Wistar albino rats were divided into four groups: Control (C), Morphine Dependence (M), Morphine Dependence + Morphine Withdrawal (MN), and Morphine Withdrawal (N).Morphine dependence was induced in the M and MN groups.Before decapitation, the rats were evaluated for behavioral changes and scored according to the Geller-Holtzman scale.After decapitation, one testicular tissue sample was placed in Krebs solution for contraction analysis, while the other was fixed in formaldehyde for histopathological examination.Testicular capsule contraction tensions, withdrawal scores, and modified Johnsen scores were assessed.Results: When the effects of morphine withdrawal were examined in rats injected with morphine, a significant difference was found between the C and MN, C and N, and M and MN groups (p<0.001).In isolated organ bath experiments, a significant difference in contraction values before drug application was observed between the C and MN groups (p<0.05);however, no significant difference was found in group-time values (p>0.05).Histological analyses of testicular tissue sections from the morphine group revealed a decrease in germinal layer thickness and degeneration in the seminiferous tubules.Histopathological examination of testicular tissues showed that the M group exhibited negative effects, while these effects were reversed in the MN group. Conclusion:At the cellular level, morphine was observed to have negative effects on testicular function, which could be reversed with naloxone.The testicular capsule contraction parameter was not clearly informative.In the morphine addiction model, more detailed insights into testicular contraction functions may be obtained by extending the application period and conducting dose-dependent studies.