Reduction of vasoconstriction mediated by neuropeptide Y Y2 receptors in arterioles of the guinea-pig small intestine.
Brief applications of a high-K+ solution were used to evoke transient constrictions of arterioles from the guinea-pig small intestine. Analogues of neuropeptide Y (NPY) selective for Y2-receptors reduced the constrictions, whereas NPY or a Y1-selective analogue potentiated the constrictions. We conclude that arteriolar smooth muscle has both Y1 and Y2 receptors, and suggest that Y2 receptors inhibit vasoconstriction by modulating the opening of voltage-sensitive Ca2+ channels. This may be related to the role of NPY that is present in some vasodilator nerves.
Neild
T O
TO
Department of Human Physiology, Flinders University, Adelaide, Australia.
Lewis
C J
CJ
D000818:Animals; D001160:Arterioles / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D005260:Female; D006168:Guinea Pigs; D007082:Ileum / Q000098:blood supply* / Q000187:drug effects; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009478:Neuropeptide Y / Q000031:analogs & derivatives / Q000494:pharmacology* / Q000502:physiology; D010446:Peptide Fragments / Q000494:pharmacology; D019894:Peptide YY; D011188:Potassium / Q000494:pharmacology; D017476:Receptors, Neuropeptide Y / Q000819:agonists / Q000187:drug effects / Q000378:metabolism*; D014661:Vasoconstriction / Q000187:drug effects*
D009478:Neuropeptide Y; D010446:Peptide Fragments; D017476:Receptors, Neuropeptide Y; C084653:neuropeptide Y (24-36), Ac-(Leu(28,31))-; C078948:peptide YY (13-36); D019894:Peptide YY; C062259:neuropeptide Y, Leu(31)-Pro(34)-; C087872:neuropeptide Y (24-36) amide, N-acetyl-(Leu(28,31))-; D011188:Potassium; D002118:Calcium