SERUM CONCENTRATION OF THYROID HORMONES AND THYROID STIMULATING HORMONE IN ALLOXAN-INDUCED TYPE 1 DIABETIC WISTAR ALBINO RATS

Background: Literature has reported thyroid functional abnormalities in diabetes mellitus. The objectives of this study were to determine and compare the serum concentrations of T3, T4 and TSH in alloxan-induced type 1 diabetic and control Wistar albino rats. Materials & Methods: It was an experimental animal study on 20 Wistar albino rats, extending over a period of eight weeks. Alloxan, a diabetogenic agent, was used to produce animal models of type 1 diabetes. Animals were divided equally into two groups: control and diabetic. The animals in the diabetic group were injected intraperitoneally with 150 mg/kg body weight of 10% alloxan to induce diabetes. After 72 hours, diabetes was confirmed with glucometer (glucose >350mg/dl). During the course of experiment, one rat in control group and 2 rats in diabetic group died. Blood was collected for estimation of serum concentrations of thyroid hormones, thyroid stimulating hormone at the end of experimental period. Serum T3, T4, and TSH were measured using ELISA kits. Results: At the end of eight weeks, the mean concentration of serum T3 was 0.69 ±0.29 ng/ml and 0.44±0.02 ng/ml in control and diabetic groups, respectively. The mean concentration of T4 was 3.78±1.16 μg/dl and 2.24±0.86 μg/dl in control and diabetic groups respectively. The mean concentration of TSH was 0.77±0.20 μU/ml and 1.41±0.23 μU/ml in control and diabetic groups respectively. The mean serum concentrations of T3 (p=.0025) and T4 (p=<.00001) were significantly lower in diabetic and that of TSH (p=<.00001) were significantly higher in diabetic than control group. Conclusion: This study concludes that the serum concentrations of both T3 and T4 are significantly lower and that of TSH is significantly higher in alloxan-induced type 1 diabetic as compared to control group in Wistar albino rats.