Conditions: Vascular Reaction to Medications
Keywords: Hand vein sensitivity phenylephrine nitroglycerin
Allocation: NON_RANDOMIZED | Intervention model: PARALLEL
Enrollment: 106
Healthy volunteers: yes

Brief summary:
The goal of this project is to determine the genetic factors contributing to interindividual differences in response to physiological and pharmacological vasoconstrictors and vasodilators.

Detailed description:
The dorsal hand vein model is a relatively non-invasive and robust experimental model to examine the local in vivo effect of vasoactive drugs without elucidating systemic counterregulatory reflexes. Infusion of incremental low doses of phenylephrine into a dorsal hand vein results in increasing local venoconstriction, without systemic effects. Similarly, infusion of incremental low doses of nitroglycerin into a preconstricted dorsal hand vein results in increasing local venodilation, without systemic effects. Systemic vascular responses can be measured by the cold pressor test (CPT),that leads to increase in blood pressure and heart rate , or mental stress that is also known to stimulate cardiovascular responses. Individuals vary in their local and systemic vascular responses but the genetic determinants of these are not clear.

Arms:
arm 1: Subjects' hand veins will be measured for maximum constriction while being infused with phenylephrine, and then mental stress and cold pressor testing arm 2: Subjects' hand veins will be measured for maximum constriction while being infused with phenylephrine, and then mental stress and cold pressor testing

Interventions: intervention 1: Phenylephrine
Intervention descriptions: intervention 1: Intravenous phenylephrine at low doses (approximately 10 doses ranging from 0-5000 ng/min) Intravenous nitroglycerin at low doses (approximately 10 doses ranging from 0.05-100 ng/min)

Protocol document: