Dr. Santollo's research is focused on understanding how gonadal hormones, specifically estrogens, contribute to sex differences in fluid and energy homeostasis. Estrogens reduce water, salt, and food intakes and blood pressure in females but the exact mechanisms by which this occurs is unknown. Current research projects focus on (1) identifying the estrogen receptor subtypes and populations which underlie these behavioral changes, (2), investigating estrogen receptor specific effects on the cell signaling pathways downstream of the angiotensin type 1 receptor, (3) investigating the role of aging on fluid and energy homeostasis in females, and (3) identifying and exploring sex differences in the renin-angiotensin system.