[The effect of pH on the passive transport of Ca2+ by membranes of fragmented sarcoplasmic reticulum of skeletal muscles].
The initial rate of Ca2+ translocation in vesicular preparations of the sarcoplasmic reticulum membranes is shown to fall with a pH decrease to 6.0 or 5.0 and to rise with a pH change to 7.0 to 7.8 in respect to the initial 6.5. It is established that the Ca2+ sorption by the membranes or their fluidity make no essential contribution to the recorded changes of 45Ca2+ level in the membrane preparations. It is shown that the passive Ca2+ transport depends to a considerable extent on the concentration of a proton at the outer surface of the sarcoplasmic reticulum membrane: an excess of H+ inhibits the Ca2+ input and output, while a decrease of the proton concentration promotes an increase in the rate of these processes in the sarcoplasmic reticulum.
Tugaĭ
V A
VA
Kurskiĭ
M D
MD
Diadiusha
G P
GP
Zakharchenko
A N
AN
D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007425:Intracellular Membranes / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism* / Q000648:ultrastructure; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000378:metabolism* / Q000648:ultrastructure
D002118:Calcium
Vliianie pH na passivnyĭ transport Ca2+ membranami fragmentirovannogo sarkoplazmaticheskogo retikuluma skeletnykh myshts.