PLASMA NOREPINEPHRINE CHANGES AFTER AROUSAL AND EXERCISE WERE ENHANCED IN CONSCIOUS PIGS WITH PERINEPHRITIC HYPERTENSION

This study found that pigs in the early stages of perinephritic hypert ension had enhanced plasma norepinephrine (NE) and heart rate (HR) res ponses to behaviorally arousing stimuli (lifting in a canvas sling) an d exercise. In the hypertensive animals, the increase in plasma NE in response to behavioral arousal caused by lifting was double that of th e intact group, and the HR response was 50% greater. The increase in p lasma NE in response to exercise was six times greater in hypertensive pigs. By contrast, mean arterial pressure changes were not enhanced i n the hypertensive group. Exaggerated catecholamine responses in plasm a to lifting and exercise stimulation were present when hemodynamic re sponses were not exaggerated.