Phosphate ion transport in rabbit brain synaptosomes.
Synaptosomes (vesicles of nerve endings) isolated from rabbit brain were studied as a model system for the uptake of inorganic phosphate. The phosphate uptake showed a sodium-dependent, saturable component with a Kt of 0.29 mM. The sodium-dependent component was larger at pH 6 than at pH 7.4 or 8. Application of potassium salts, ouabain, monensin, nigericin or FCCP decreased the uptake. The results indicate that the sodium-sensitive phosphate influx is dependent on the Na+ gradient and on the membrane potential, which might act, preferentially, on the transport of the monovalent phosphate ion.
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002540:Cerebral Cortex / Q000378:metabolism*; D007700:Kinetics; D008985:Monensin / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D010710:Phosphates / Q000378:metabolism*; D011817:Rabbits; D012964:Sodium / Q000494:pharmacology; D013574:Synaptosomes / Q000378:metabolism*
D010710:Phosphates; D010042:Ouabain; D008985:Monensin; D012964:Sodium