[Effect of taurine on the properties of myocardial sarcoplasmic reticulum guanyl cyclase].
Effect of taurine on the properties of guanylate cyclase (GC) of the guinea-pig cardiac sarcoplasmic reticulum was studied. The enzymatic activity increased in the presence of Mn+2 at a concentration of 0.05 mM, reaching the maximal level at a concentration of 7 mM. Mg2+ (0.25-1 mM) did not alter the activity of GC in the absence of Mn2+, but stimulated it in the presence of Mn2+ at a concentration ranging within 0.1 to 1 mM. Taurine activated GC in the presence of Mn2+ (10 mM) and produced no effect on its activity at 0.5-3 mM of Mn2+ without Mg+2. Taurine (0.4-10 mM) potentiated the activity of GC stimulated with Mg+2. The structural analog of taurine, beta-alanine, suppressed the activity of GC 2-2.5-fold both in the absence and presence of Mg+2. Ca2+ (10(-9)--10(-4) mM) stimulated GC. Effect of Mg+2 and taurine on GC activity rose proportionally to an increase in Ca+2 concentration in the incubation medium. The data obtained evidence in favour of potential monitoring of the activity of GC through changes in the intracellular content of Ca+2, Mg+2 and taurine in the presence of Mn+2 at concentrations close to the physiological ones. The effect of taurine on GC is mediated via Mg+2 and Ca+2.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D004789:Enzyme Activation; D006162:Guanylate Cyclase / Q000378:metabolism*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D009206:Myocardium / Q000201:enzymology*; D012519:Sarcoplasmic Reticulum / Q000201:enzymology; D013654:Taurine / Q000494:pharmacology*; D015091:beta-Alanine / Q000494:pharmacology
D015091:beta-Alanine; D013654:Taurine; D008345:Manganese; D006162:Guanylate Cyclase; D008274:Magnesium; D002118:Calcium
Vliianie taurina na svoĭstva guanilattsiklazy sarkoplazmaticheskogo retikuluma serdtsa.