Effect of Experimentally Induced Hypothyroidism on thyroid gland and ovary of albino rat and the possible protective effects of Vitamin E

Background: Thyroid hormones are important for reproduction. The disturbance in their levels were affect the proper functions of the ovary impairing fertility. Aim of the work:Our study aimed to examine the effect of induced hypothyroidism on both thyroid gland and ovaries in adult albino rats, and investigate their reversibility and the protective effects of vitamin E. Materials and Methods:40 adult female rats were subdivided into three groups:The control group, 10 rats, was received no drugs, The 2nd group included 15 rat was treated with daily dose of carbimazole (1.35mg/kg b.w /day) given orally for 8 weeks. The third group included 15 rats were treated with carbimazole by the same dose as the second group and co-administered with vitamin E, by dose (100 mg/kg) orallyfor 8 weeks, at the end of the experiment,thyroid glands and ovaries were dissected and prepared for histological analysis. Results: In control groups, thyroid gland sections revealed normal follicular structure,their lumen was filled with colloid. In 2nd group, show irregular shape in some follicles, with reduction in colloid amount, in 3rd group showing mixture of control and hypothyroidism groups. In ovarian sections of control group, show that the ovary is divided into a cortex and medulla which contain different stages of ovarian follicles, in 2nd group showing degenerated follicles and oocytes, while in3rd. group,a number of growing follicles with dilated blood vessels,corpus luteum observed. Conclusion:we concluded that experimentally induced hypothyroidism produces changes in the thyroidal and ovarian structure. These changes can reversed to approximately normal by vit.E