AbstractThis study focuses on the relationship between serum levels of cholesterol and homocysteine with that of total antioxidant capacity in rats with thyroid dysfunction.Adult male Wistar rats were divided into three groups, a control (euthyroid), hypothyroidism and hyperthyroidism, each of them containing ten rats. Hypothyroidism was induced by administration of 0.1% aminotriazole in drinking water for 3weeks. Hyperthyroidism was induced by chronic subcutaneous injection of l-thyroxine (100μg/day, dissolved in 200μL saline solution/100g body weight) for 3weeks. The control and hypothyroid groups were injected subcutaneously with the same volume of saline solution.Results showed that hyperthyroidism is characterized by reduced serum thyr...