Tachykinin NK1 receptor-mediated vasorelaxation in human pulmonary arteries

Eur J Pharmacol. 1998 May 29;350(1):R1-3. doi: 10.1016/s0014-2999(98)00310-0.

Abstract

Tachykinin NK1 receptors are present on human pulmonary arteries. Addition of the specific tachykinin NK1 receptor agonist, [Met-OMe11]substance P produced a concentration-dependent relaxation (0.1 nM to 100 nM) in pulmonary arteries preconstricted with phenylephrine (30 microM). The EC50 (agonist concentration needed to produce 50% of the maximal relaxation) value for [Met-OMe11]substance P was 3.7+/-0.7 nM. The relaxation induced by [Met-OMe11]substance P was selectively inhibited by the tachykinin NK1 receptor antagonist CP 99994 (1 nM), with a pKb of 9.9+/-0.3. Treatment with the tachykinin NK2 receptor antagonist SR 48968 (100 nM) did not significantly affect the vasorelaxation due to [Met-OMe11]substance P (P > 0.05, one-way analysis of variance; ANOVA).

MeSH terms

  • Dose-Response Relationship, Drug
  • Humans
  • Phenylephrine / pharmacology
  • Piperidines / pharmacology
  • Pulmonary Artery / drug effects
  • Pulmonary Artery / metabolism
  • Pulmonary Artery / physiology*
  • Receptors, Neurokinin-1 / drug effects
  • Receptors, Neurokinin-1 / physiology*
  • Substance P / pharmacology
  • Vasoconstrictor Agents / pharmacology
  • Vasodilation* / drug effects

Substances

  • Piperidines
  • Receptors, Neurokinin-1
  • Vasoconstrictor Agents
  • 3-(2-methoxybenzylamino)-2-phenylpiperidine
  • Phenylephrine
  • Substance P