[Membrane potential during Ca++ transport and AMP deamination in vesicles of the sarcoplasmic reticulum].

Transport of Ca2+ to vesicles of the sarcoplasmic reticulum and its subsequent removal by AMP is accompanied by fluorescence intensification and quenching, respectively, of the charged potentially-dependent probes of 1-anilino-8-naphthalenesulphonate and 3,3'-dipropilthiodicarbocyanin as well as 4-dimethylaminochalcone responding to conformation changes in membranes. The transmembrane electrophoretic distribution of synthetic fat-soluble ions of phenyldicarboundecaborane and tetraphenylphosphonium during Ca2+ accumulation is characterized by uptake of phenyldicarboundecaborane with the subsequent removal by protonophore of m-cholorocarbonylcyanide phenylhydrazone or AMP; the uptake of tetraphenylphosphonium is absent. This testifies to the fact that the Ca2+ transport in vesicles is accompanied by the formation of a membrane potential with a positive sign inside the vesicles.