The sympathetic nervous system response to stress in chronic vitamin E-deficient rats

This study was undertaken to examine whether some stressful conditions affected urinary output of catecholamine of 3- and 18-month-old vitamin E-deficient rats and control rats. Basal levels of urinary norepinephrine (NE) and epinephrine (E) excretion of aged vitamin E-deficient rats was 2- to 3-fold higher than those of control rats. In both groups of young rats, cold exposure, administration of insulin, and immobilization stress provoked a marked increase in urinary output of NE, E, NE and E, respectively. However, the urinary catecholamine responses to these stresses were markedly diminished in aged rats. No significant changes were observed in excretion of catecholamine during these stresses in aged rats receiving vitamin E-deficient diet. Therefore, these results suggested that the responses of sympathetic nervous activity to these stresses were significantly lowered in the chronic vitamin E-deficient rats compared to control rats.