Neuropeptide Y in human hand veins: pharmacologic characterization and interaction with cyclic guanosine monophosphate-dependent venodilators in vivo.
The dorsal hand vein compliance technique was used to study direct vascular effects of human neuropeptide Y in vivo. Human neuropeptide Y is an endogenous vasoconstrictor peptide that is costored with norepinephrine in sympathetic nerve endings and coreleased with the catecholamine under various physiologic and pathologic conditions. Compared with the alpha 1-adrenergic agonist phenylephrine (geometric mean dose-rate that produces the half-maximal response [ED50]: 1.05 nmol/min; maximum venoconstriction [Emax] +/- SEM, expressed as a percentage of baseline compliance: 91% +/- 3%), human neuropeptide Y was nine times more potent (geometric mean ED50: 0.122 nmol/min; p < 0.001) but markedly less efficacious (Emax: 58% +/- 4%; n = 12; p < 0.001). Venoconstrictor effects of human neuropeptide Y lasted several hours and were unchanged by simultaneous administration of alpha-adrenergic antagonists but were readily reversed by nitroglycerin or bradykinin. The high responsiveness of subcutaneous veins to human neuropeptide Y indicates that human neuropeptide Y may regulate venous compliance and filling of the venous subcutaneous capacitance bed in vivo.
Department of Internal Medicine, University Hospital, Basel, Switzerland.
P
P
Peduzzi
D
D
Simper
L
L
Linder
W M
WM
Strobel
W E
WE
Haefeli
D000328:Adult; D001920:Bradykinin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D006157:Guanosine Monophosphate / Q000502:physiology*; D006801:Humans; D008297:Male; D009478:Neuropeptide Y / Q000502:physiology*; D005996:Nitroglycerin / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D012016:Reference Values; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology
D009478:Neuropeptide Y; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D010656:Phenylephrine; D006157:Guanosine Monophosphate; D005996:Nitroglycerin; D001920:Bradykinin