We studied changes in the hypothalamic norepinephrine(NE) metabolism in streptozotocin (STZ)-induced diabetic rats by measuring basal NE levels, turnover rate of NE, and in vivo tyrosine hydroxylase activities. Basal NE level did not change significan...
We studied changes in the hypothalamic norepinephrine(NE) metabolism in streptozotocin (STZ)-induced diabetic rats by measuring basal NE levels, turnover rate of NE, and in vivo tyrosine hydroxylase activities. Basal NE level did not change significantly upto 4 weeks after the establishment of diabetes with STZ(60 mg/kg, iv). But turnover rate of NE decreased to 62% of control rate(P<0.01), and in vivo tyrosine hydroxylase activities decreased to 32% of control level(P<0.05) at one week of diabetes. From these results, we concluded that, of the three parameters measured, in vive tyrosine hydroxylase activity is the most sensitive index of altered hypothalamic NE metabloism in STZ-induced diabetic rats.