Aluminum inhibits the lysosomal proton pump from rat liver

Lysosomes are cytoplasmatic organelles, delimitated by a single lipoprotein membrane, that contain several enzymes mostly belonging to the hydrolases in that they function mainly for intracellular digestion. Lysosomal internal pH is characteristically acidic and it is maintained around pH 4.5 by a proton pump, an ATPase, that uses energy from ATP hydrolysis to translocate H+ ions into lysosomes. In the presence of Al3+ the proton pump activity is markedly reduced compromising acidic vesicles functionality. Among different species utilized, Al2(SO4)3 and AlF3 were the most effective. Aluminum effect was not observed when the delta pH was produced artificially by nigericin.