Changes of glucose transporter 2 in rat livers with different thyroid state

  Objective   To study the effect of g lucose transpor ter 2(GLUT2)on impaired g lucose tolerance in hyperthy ro id rat.

  Methods   For ty male Wistar rats were divided intofour groups: hy pothyroidism, lighthyperthyroidism, serious hy per thyroidism and normal groups.Every group included ten rats.Induction of hypo or hyperthyroidism: Every hypothy roidism rat received 10 mg methimazole every day.Every lighthyperthyroidism rat received 100 μg L-thyrox ine while every serious hyperthy roidism rat received 20μg L-thyrox ine everyday.The control group received saline everv day.After 28 days, the concentrations of blood glucose, insulin, T₃ and T₄ were examined and GLUT2 were detected by Western blot.

  Results   The concentrations of blood glucose, insulin and GLUT2 increased significantly in light and serious hy perthyroidism rats while IAI decreased significantly.Compared with lishthyperthyroidism, GLUT2 and blood tnsulin increaseed while IATdecreased sig nificantly in serious hyperthyro idism.The concentrations of blood glucose, insulin and IAI in hypothyroidism did not change significantly.The concentrations of GLUT2 in the hypothyroidism rats decreased significantly.Blood glucose, insulin andIAI had positive sig nificant correlation with GLUT2.

  Conclusion   The changes of GLUT2 concentrations in the liver cell membrane probably contr ibuted to abnormal g lucose metabolism in hyperthyroidism.