Pulmonary Physiology and Hypoxia
The principal focus in the Pulmonary Physiology Research Laboratory continues to be the autonomic and hemodynamic responses to hypoxia (low blood oxygen levels) using intact animal models and human volunteers. Studies are designed to better define the causal connections between (continuous and intermittent) hypoxic exposure and sustained sympathoexcitation and hypertension. Studies utilizing rat and rabbit models of intermittent hypoxia focus on neuromodulatory changes in the carotid chemoreceptor and central nervous system (CNS) that promote sympathoexcitation. In the peripheral chemoreceptor the focus is on endothelin and nitric oxide (NO), while in the CNS the focus is on NO and angiotensin. Human studies use brief (20 minute), intermediate (8 hours), and prolonged (days) exposures to hypoxia to better understand hypoxic acclimatization and the sympathetic response to chemostimulation. Arterial infusion of selective pharmacological agents is used to identify changes in endogenous vasoactive agents and d=microneurography is used to assess sympathetic activity.