EFFECTS OF NICORANDIL ON PHYSIOLOGICAL PROPERTIES OF GUINEA PIG PAPILLARY MUSCLES / 中国药理学通报

ABSTRACT

The effects of nicorandil ( NICO ) on the contractility, automati -city, excitability, functional refractory period ( FRP ) & dose-response curves for isoprenaline as well as calcium were studied in guinea pig papillary muscles. NICO could decrease the amplitude of contraction of papillary muscles dose-dependently. Propranolol and NICO might antagonize the inotropic effect of isoprenallne. Verapamil & NICO induced Ca2+ antagonistic effects in a non-competitive manner, & the maximal Ca2+ response of papillary muscles decreased signifi- cantly. The automaticity of papillary muscles was decreased Significantly when the concentration of NICO reached 1.4 mmol/L, but exerted no effect on their excitability & the functional refractory period.