Hydrogen sulphide regulates intracellular pH in vascular smooth muscle cells

Biochem Biophys Res Commun. 2007 Jul 13;358(4):1142-7. doi: 10.1016/j.bbrc.2007.05.063. Epub 2007 May 21.

Abstract

We investigated the role of hydrogen sulphide (H(2)S) in intracellular pH (pH(i)) regulation in vascular smooth muscle cells and its contribution on vasodilation. NaHS, a H(2)S donor, decreased pH(i) in a concentration-dependent manner ranging from 10 microM to 1mM. Neither inhibition of the Na(+)/H(+) exchanger with 5-(N-ethyl-N-isopropyl) amiloride, (EIPA, 10 microM), nor plasmalemmal Ca(2+)-ATPase with CdCl(2) (20nM) alters the effect of NaHS on pH(i). Blockade of the Cl(-)/HCO3- exchanger with 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) significantly attenuated the pH(i) lowering effect of NaHS. Moreover, NaHS significantly increased the activity of Cl(-)/HCO3- exchanger when measured with NH(4)Cl prepulse method. DIDS attenuated the vasorelaxation induced by NaHS whereas EIPA and CdCl(2) did not cause any change. In conclusion, H(2)S induced intracellular acidification via activation of Cl(-)/HCO3- exchanger, which is, at least partially, responsible for H(2)S-mediated vasorelaxation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Hydrogen Sulfide / administration & dosage*
  • Hydrogen-Ion Concentration / drug effects*
  • Intracellular Fluid / chemistry
  • Intracellular Fluid / drug effects
  • Muscle, Smooth, Vascular / chemistry*
  • Muscle, Smooth, Vascular / drug effects*
  • Myocytes, Smooth Muscle / chemistry*
  • Myocytes, Smooth Muscle / drug effects*
  • Rats

Substances

  • Hydrogen Sulfide