histological study on the effect of experimentally induced hyperthyroidism on adult albino rat testis

ABSTRACT

The thyroid hormone is a regulator of growth, development and metabolism in all tissues, and an altered thyroid status affects many organs. Studies correlating male sexual function with thyroid disorders are limited, probably because thyroid disorders are limited in men. The present work aimed to throw light on the effect of experimentally induced hyperthyroidism on the testes of adult albino rats with respect to testicular morphology, androgen receptor [AR], proliferating cell nuclear antigen [PCNA] and connexin43 [CX43] protein. Eighteen adult albino rats were used in this study and were divided into three groups of six rats each. Group I received 0.5 ml saline solution by intraperitoneal injection once daily for 4 weeks. Group II received an intraperitoneal injection of 40microg/kg L-thyroxin dissolved in saline solution daily for 4 weeks. Group III received thyroxin as in group II and were sacrificed 1 month after cessation of drug administration. Before scarification, serum thyroxin [T4] levels were determined. Sections were subjected to H and E and immunohistochemical staining for anti-AR, anti-PCNA and anti-connexin 43 antibodies. Morphometric studies included determination of the area% of immune reactions. In group II, the seminiferous tubules were lined by scanty apoptotic cells. There was homogeneous material between the seminiferous tubules. There was a significant decrease in the mean area% of anti-androgen, anti-PCNA and anti-CX43 antibodies compared with the control group. In group III the seminiferous tubules were apparently normal in shape and contained sperm in their lumen, separated by interstitial tissue. Although the mean area% of anti-AR, anti-PCNA and anti-CX43 was still lower, only the anti-PCNA antibody showed significant difference when compared with the control group. The current study showed that hyperthyroidism induced pronounced morphological changes in the testis