title: S-100 alpha-like immunoreactivity in tubules of rat kidney. A clue to the function of a "brain-specific" protein.
abstract: The localization of the alpha and beta subunits of S-100 protein was studied in normal tissue where the identification of three subclasses of S-100 containing cells was derived: i) cells that contain both alpha and beta subunits; ii) cells that contain only the alpha subunit; and iii) cells that contain only the beta subunit. In this study monospecific antibodies against the S-100 alpha and beta subunits were used to characterize the S-100-like immunoreactivity in the rat kidney: Certain cells in the distal nephron, i.e., the connecting piece, collecting ducts, and the thin limb of Henle's loop, contained S-100 alpha immunoreactivity. Proximal tubules, the thick ascending limb of Henle's loop, the distal tubules, and the juxtaglomerular apparatus were negative. No S-100 beta immunoreactivity was found in kidney tubules. However, Schwann cells of renal pelvic nerves contained S-100 beta immunoreactivity. The presence of S-100 alpha antigen in certain cells of the kidney gives further support to the assumption that the alpha subunit of S-100a is related to cells that are highly involved in pH, electrolyte, and water regulation.
mesh_terms: D000818:Animals; D015415:Biomarkers; D006801:Humans; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D007672:Kidney Cortex / Q000032:analysis; D007684:Kidney Tubules / Q000032:analysis*; D008297:Male; D009414:Nerve Growth Factors; D051381:Rats; D011919:Rats, Inbred Strains; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000032:analysis*; D013361:Sublingual Gland / Q000032:analysis
chemical_list: D015415:Biomarkers; D009414:Nerve Growth Factors; C030564:S-100 calcium-binding protein alpha subunit; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins