[Effect of oxygen and nitrogen active compounds on pH value in myometrium myocytes].

In suspension from a rat uterus using fluorescent pH1 probe BCECF-AM was established that the "apparent" pH1 value for this object was 6.72 +/- 0.02 at pHo = 7,4 (t = 25 degrees C, n = 5). Cell activation by 0.1 mM carbachol was accompanied by a rise in cytosolic pH up to 6.81 +/- 0.01. This process with different efficiency was inhibited by blockers of K(+)- and H(+)-channels: 0.1 mM 4-amidopyridine, tetraethilamonium and cadmium. The blockers of passive H(+)-transport do not inhibit completely alkalization of myoplasm that can testify in the favor of the non-channel way of passive transport H+ through plasmalemma. It was established that NO (0.1 mM sodium nitroprusside) and NO2- (10 nM) significantly enhanced the carbochol-induced rise of myoplasm pH in the cells from myometrium. It also was shown that carbachol-induced pH. in myocytes was increased by the addition of 10 nM H2O2. It was suggested that the studied compounds could influence Ca2+ transport systems by changing pH in myocytes.