Effects of vitamin E and sodium selenate on neurogenic and endothelial relaxation of corpus cavernosum in the diabetic mouse

We, studied the effect of vitamin E and sodium selenate treatment on the ne urogenic and endothelium-dependent relaxation of isolated corpus cavernosum obtained from streptozotocin-induced diabetic mice. Relaxant responses of corpus cavernosum precontracted by phenylephrine to electrical field stimul ation and to acetylcholine were significantly decreased in diabetic mice. T here was no significant difference between diabetic and non-diabetic groups for the relaxant response of corpus cavernosum to sodium nitroprusside and papaverine. Treatment with sodium selenate, but not vitamin E, partially p revented the impairment of the neurogenic relaxation, whereas both had a si gnificant, partial restorative action on endothelial dysfunction in corpus cavernosum obtained from diabetic groups. Neither agent exhibited a signifi cant action on the relaxant responses of corpus cavernosum obtained from no n-diabetic mice. A decrease in the sensitivity of the neurogenic impairment to antioxidant action may develop more rapidly than that of endothelial dy sfunction in streptozotocin-induced diabetic mice. (C) 2000 Elsevier Scienc e B.V. All rights reserved.