Early effects of experimental diabetes on central catecholamine concentrations

Six days after induction of diabetes norepinephrine (NE), 3,4-dihydroxyphenylalanine and dopamine concentrations were determined in spinal cord, cerebellum, pons/medulla oblongata and the remaining brain of diabetic rats. Only cerebellar NE levels were significantly increased by 21% compared to age-matched controls. This effect was not seen when diabetic rats received insulin replacement therapy. Fifty-two days after induction of diabetes cerebellar NE levels in diabetic rats were further increased (+37%), implying an enduring and progressive effect. The data show that even with a short period of uncontrolled diabetes central neurochemical alterations occur.