Article: article from journal or magazin.
Human neuropeptide Y potentiates alpha1-adrenergic blood pressure responses in vivo
American Journal of Physiology. Heart and Circulatory Physiology
3 Pt 2
Clinical Trial Controlled Clinical Trial Journal Article Research Support, Non-U.S. Gov't --- Old month value: Sep
Human neuropeptide Y (hNPY) potentiates the postjunctional vasoconstrictor effects of alpha1-adrenoceptor agonists in animals and in human hand veins in vivo. We therefore hypothesized that such an interaction might also occur in the human arterial bed. With the present single-blind cross-over study in 12 healthy volunteers, the effect of subpressor doses of hNPY on the blood pressure response to alpha1-adrenoceptor stimulation was evaluated. Dose-response curves were constructed to intravenously infuse phenylephrine with and without coinfusion with two different doses of hNPY (1.4 and 14.3 pmol . kg-1 . min-1). Blood pressure, heart rate, and forearm blood flow were recorded, and plasma hNPY was determined. During infusion of the higher hNPY dose, which increased hNPY from 24.0 +/- 12.0 to 495.1 +/- 12.6 pmol/l, blood pressure curves were 2.4-fold shifted toward lower phenylephrine dose rates (P < 0.001). Forearm vascular resistance showed a similar trend, whereas the counterregulatory decrease of heart rate was similar in both groups. In contrast, the lower hNPY dose rate producing a fourfold increase in hNPY concentrations did not modify the response to phenylephrine. This in vivo study in humans demonstrates that hNPY induced potentiating effects on alpha1-adrenergic constriction also in the systemic arterial circulation and suggests that circulating hNPY may participate in the control of vascular tone.
Adrenergic alpha-Agonists/*pharmacology Adult Blood Pressure/*drug effects Cross-Over Studies Dose-Response Relationship, Drug Drug Synergism Female Forearm/blood supply Heart Rate/drug effects Humans Male Neuropeptide Y/administration & dosage/*pharmacology Phenylephrine/administration & dosage/*pharmacology Vascular Resistance/drug effects
Web of science
Last modification date