Autonomic Control of the Circulation and VDR

The study objective of this project is to examine the mechanisms of the venous distension reflex (VDR) in humans. We hypothesize that COX blockade with ketorolac tromethamine, an intravenous NSAID, will attenuate the muscle sympathetic nerve activity (MSNA) response to limb venous distension. To gain further insight into whether the COX byproducts directly stimulate chemically-sensitive afferents, or enable venodilation and indirectly evoke afferent stimulation, we will measure vein size using 3T MRI during venous distention with and without ketorolac infusions.

NCT Number	NCT03513770
Lead Sponsor	Milton S. Hershey Medical Center Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
Conditions	Venous Distension Reflex, Blood Pressure
Enrollment	18 participants
Start Date	2019-08-14
Primary Completion	2026-11-01 (estimated)
Study Completion	2027-11-01 (estimated)
Updated on ClinicalTrials.gov	2026-07-09