Sub-Chronic Effects of Gibberellic Acid Repeated Exposure on the Testis of Adult Albino Rats (Biochemical, Histopathological and Immunohistochemical Study)

Document Type : Original Article

Authors

1 Departments of Forensic Medicine & Clinical Toxicology, Faculty of Medicine, Zagazig University, Zagazig, Egypt

2 Departments of Histology and Cell Biology, Faculty of Medicine, Zagazig University, Zagazig, Egypt.

Abstract

Objective: Gibberellic acid (GA3) is a plant growth regulator (PGR), largely used in agriculture in many countries including Egypt. The purpose of this study was to investigate the effects of sub-chronic toxicity (8 weeks) of GA3 on testicular function and structure in adult albino rats, and to determine the effects of withholding of GA3 on the affected parameters for another 8 weeks of follow up period.  Material and Methods: Forty adult male albino rats were equally divided into four groups; the first group was used as a negative control, the second group received 1ml of 1N NaOH (positive control group), the third group received 75 ppm of GA3 daily in drinking water for 8 weeks (GA3 group), and the last group received the same treatment as the third group for 8 weeks then was left without any treatment for another 8 weeks (recovery group). At the end of the experimental period, rats were sacrificed and the testes were examined by light and transmission electron microscope for detecting the histopathological changes, examination of sperm viability & count and measuring testicular malondialdhyde. Testicular sections were examined immunohistochemically for the detection of the anti-apoptotic Bcl-2 protein. Results:  In GA3 treated group, histopathological changes were in the form of regression in spermatogenesis using light microscope, while electron microscopic examination revealed apoptotic changes in the Leydig cells and distortion of the adluminal compartment. These changes were accompanied by significant elevation in testicular malondialdehyde, while Bcl-2 showed week immunoreactions in the layers of spermatids. After the 8 weeks of GA3 withholding, significant improvement in the testicular function and structure with improvement of Bcl-2 immunoreaction.  Conclusion: From the previous results, it can be concluded that GA3 exposure can induce reversible toxic changes in the testes of adult albino rats on sub-chronic exposures.

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