Pimaric acid reduces vasoconstriction via BKCa channel activation and VDCC inhibition in rat pulmonary arterial smooth muscles

J Pharmacol Sci. 2023 Oct;153(2):84-88. doi: 10.1016/j.jphs.2023.08.001. Epub 2023 Aug 10.

Abstract

Pulmonary vessels play a pivotal role in oxygen circulation. We previously demonstrated that pimaric acid (PiMA) activated large-conductance Ca2+-activated K+ (BKCa) channels and inhibited voltage-dependent Ca2+ channels (VDCCs). In the present study, PiMA attenuated vasoconstriction induced by high K+ or endothelin-1 in rat pulmonary arterial smooth muscles (PASMs). PiMA also reduced high K+-induced cytosolic [Ca2+] increase in PASM cells. PiMA increased BKCa currents and decreased VDCC currents. BKCa channels and VDCCs were formed by the α/β1 and α1C1D23 subunits, respectively. These results indicate that PiMA induces vasorelaxation through the dual effects of BKCa channel activation and VDCC inhibition in PASMs.

Keywords: Ion channel; Pimaric acid; Pulmonary artery.

MeSH terms

  • Animals
  • Calcium Channels, L-Type
  • Hypertension, Pulmonary*
  • Muscle, Smooth
  • Potassium Iodide
  • Rats
  • Vasoconstriction*

Substances

  • pimaric acid
  • Calcium Channels, L-Type
  • Potassium Iodide