[Delta pH-induced transport of Ca 2+ into smooth muscle plasma membrane vesicle fraction].
Using the fluorescent dye acridine orange, the feasibility of formation in myometrium sarcolemma of closed inside-out oriented vesicles and of a proton gradient created by the pH-jump method and stable in time, was demonstrated. At the initial value of delta pH = 2, the characteristic time of the gradient dissipation providing for the pH change by one unity is 4 to 5 minutes. The proton gradient oriented from the intravesicular space to the environment stimulated the Ca2+ influx into the vesicles. The transmembrane gradient of H+ with the inside-out oriented sarcolemmal vesicles prevents the Ca2+ influx. It is concluded that plasma membranes of smooth muscle cells contain alongside with the ATP- and Na(+)-dependent Ca2+ transport systems also a mechanism of the delta pH-induced transport of this bivalent cation.
Kosterin
S A
SA
Fomin
V P
VP
Chervonenko
I B
IB
Shinlova
O P
OP
D000165:Acridine Orange; D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism*; D005260:Female; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D009130:Muscle, Smooth / Q000378:metabolism*; D009215:Myometrium / Q000378:metabolism*; D011522:Protons; D013050:Spectrometry, Fluorescence
D007202:Indicators and Reagents; D011522:Protons; D000165:Acridine Orange; D002118:Calcium
Del'ta pH-indutsiruemyĭ transport Ca 2+ vo fraktsii vezikul plazmaticheskoĭ membrany gladkomyshechnykh kletok.