The cellular distribution of aldolase isozymes in rat kidney and brain determined in tissue sections by the immuno-histochemical method.

The use of the immuno-histochemical method permits the localization of aldolase isozymes in tissue sections. Upon incubating a section with a monomer-specific antiserum, isozymes containing that monomer remain in the section, whereas other cytoplasmic enzymes diffuse out of the section. If soluble antigen is added subsequently, it is bound by the tissue-bound antibody. These antibody fixed aldolases can then be stained by the use of a tetrazolium test linked to substrate hydrolysis. In this way it was demonstrated that isozymes of aldolase containing mostly the A monomer are predominantly localized in the distal tubules, the collecting tubules, the vessels and capillaries of the kidney, the ganglia, the Purkinje cells, the neurons, the white matter and the chorioid plexus of the brain. Aldolase containing mostly B-monomers were found in the proximal tubules. Aldolase isozymes particularly rich in C-monomers were seen in the nervus opticus, the pia mater, the vessels of cerebrum and the molecular layer of the cortex cerebelli.