Role of calcium and potassium channels in effects of hydrogen sulfide on frog myocardial contractility

Bull Exp Biol Med. 2011 Jun;151(2):163-6. doi: 10.1007/s10517-011-1280-5.


The effects of sodium hydrosulfide NaHS, a donor of hydrogen sulfide H2S, on the force of muscle contraction were examined on isolated myocardial strips from frog ventricles. NaHS decreased the amplitude of muscle contractions in a dose-dependent manner under normal conditions and during inhibition of Ca channels with nifedipine. In contrast, under conditions of blockade of ATP-dependent potassium channels with glibenclamide, NaHS exerted a positive inotropic effect from the first minute of application. Neither blockade, nor activation of ATP-dependent K-channels with glibenclamide modulated the negative inotropic effect of NaHS. Inhibition of K-channels with tetraethylammonium (TEA) (3, 5, 10 mM) or 4-aminopyridine increased the amplitude of myocardial contractions. Preliminary application of 4-aminopyridine or TEA (3 mM) did not eliminate NaHS-induced negative inotropic effect, although higher TEA concentrations (5 or 10 mM) prevented it. The data indicate that the targets of H(2)S in frog myocardium are ATP-dependent, Ca-activated, and voltage-dependent K-channels.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4-Aminopyridine / pharmacology
  • Animals
  • Calcium Channel Blockers / pharmacology
  • Calcium Channels, L-Type / metabolism*
  • Electric Stimulation
  • Glyburide / pharmacology
  • Heart / drug effects
  • Heart / physiology*
  • Hydrogen Sulfide / pharmacology*
  • In Vitro Techniques
  • KATP Channels / agonists
  • KATP Channels / metabolism
  • Minoxidil / pharmacology
  • Myocardial Contraction / drug effects*
  • Myocardium / metabolism*
  • Nifedipine / pharmacology
  • Potassium Channel Blockers / pharmacology
  • Potassium Channels, Calcium-Activated / antagonists & inhibitors
  • Potassium Channels, Calcium-Activated / metabolism*
  • Rana ridibunda
  • Tetraethylammonium / pharmacology


  • Calcium Channel Blockers
  • Calcium Channels, L-Type
  • KATP Channels
  • Potassium Channel Blockers
  • Potassium Channels, Calcium-Activated
  • Minoxidil
  • Tetraethylammonium
  • 4-Aminopyridine
  • Nifedipine
  • Glyburide
  • Hydrogen Sulfide