 Stress has complex effects on the bodys physiology. Models of stress such as hypoglycemia have identified that stress activates the hypothalamic-pituitary-adrenal HPA axis and sympathoadrenal system acutely. Additionally, there are delayed effects of prior exposure to hypoglycemia. The day after being exposed to a hypoglycemic stimulus there are: 1 decreases in the catecholamine release to a new hypoglycemic stress; 2 decreases in the muscle sympathetic nerve activity MSNA response to either a new hypoglycemic challenge or transient hypotension; 3 decreases in cardiac vagal baroreflex sensitivity BRS; and 4 increases in sensitivity to thermal pain and altered temporal summation decreased tolerance to a repeated minimally painful stimulus. This project will test the hypothesis that these delayed changes in autonomic nervous system function are secondary to a rise in ACTH that occurs in response to stress. 