Neurokinin‐induced changes in pial artery diameter in the anaesthetized guinea‐pig

• Published in: British journal of pharmacology 1993-01, Vol.108 (1), p.146-149
• Main Authors: Beattie, D.T., Stubbs, C.M., Connor, H.E., Feniuk, W.
• Format: Article
• Language: English
• Subjects: Animals; Arteries - drug effects; Arteries - physiology; Calcitonin Gene-Related Peptide - pharmacology; calcitonin gene‐related peptide (CGRP); GR64349; GR73632; GR82334; Guinea Pigs; Male; Neurokinin A - analogs & derivatives; Neurokinin A - pharmacology; neurokinin receptors; Peptide Fragments - pharmacology; Physalaemin - analogs & derivatives; Physalaemin - pharmacology; Pia Mater - blood supply; Pial artery; Receptors, Neurokinin-2; Receptors, Neurotransmitter - drug effects; Receptors, Neurotransmitter - physiology; substance P; Substance P - analogs & derivatives; Substance P - pharmacology; vasodilatation; Vasodilation - drug effects
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1111/j.1476-5381.1993.tb13454.x

1 The effects of selective neurokinin agents on pial artery diameter, measured with an on‐line image analyser, have been studied in anaesthetized guinea‐pigs in order to characterize the neurokinin receptors present on pial arteries. 2 Perivascular injection of either substance P (0.01–1 μm) or the selective NK1 receptor agonists, substance P methyl ester (SPOMe, 0.01–1 μm) and GR73632 (0.1 μm), increased pial artery diameter. 3 In contrast, the selective NK2 receptor agonist, GR64349 (1 μm), produced a small vasoconstriction while the NK3 receptor‐selective agonist, senktide (1 μm) was inactive. 4 Co‐administration of GR82334 (1 μm), a selective NK1 receptor antagonist, inhibited the vasodilatation produced by SPOMe (0.1 μm) but not that caused by calcitonin gene‐related peptide (CGRP, 0.01 μm). 5 The results are consistent with an involvement of NK1 receptors in the neurokinin‐induced increase in guinea‐pig pial artery diameter.