Effect of diet on sympathetic nervous system activity in chronic vitamin E-deficient rats

This study was undertaken to examine the responsiveness of the sympathetic nervous system of chronic vitamin E-deficient rats to dietary changes. Rats receiving a vitamin E-deficient diet exhibited about 95% hemolysis after 4 weeks on the vitamin E-deficient diet and this value was maintained up to 18 months. alpha-Tocopherol in serum was not detectable in rats receiving the vitamin E-deficient diet for 18 months. Lipid peroxide concentration in serum of rats receiving the vitamin E-deficient diet for 18 months was 10-fold higher than that of control rats. Basal levels of urinary norepinephrine (NE) and epinephrine (E) excretion in chronic vitamin E-deficient rats was 2- to 3-fold higher than those of control rats. In control rats, urinary NE excretion declined during fasting and this decline was reversed upon refeeding. Urinary excretion of NE in control rats increased upon glucose feeding. However, in chronic vitamin E-deficient rats, no change was observed upon fasting and glucose feeding in either urinary NE or E excretion. These results suggest that the increase in basal levels of urinary NE excretion in chronic vitamin E-deficient rats was not influenced by dietary manipulation.