Evidence for particulate guanylate cyclase in rat kidney after stimulation by atrial natriuretic factor. An ultracytochemical study.
Cytochemical localization of particulate guanylate cyclase (GC) in rat kidney, after stimulation with atrial natriuretic factor (ANF), was studied by electron microscopy. In the renal corpuscle GC reaction was localized on podocytes. Other segments of the nephron that showed ultracytochemical evidence of GC activity were the proximal convoluted tubule, the thick ascending limb of the loop of Henle and the collecting tubule. All GC positivity was associated with plasma membranes. Samples incubated in basal conditions (without ANF) did not reveal any GC reaction product. These results indicate that ANF is a strong activator of particulate GC. Our data also suggests that, through the enzyme, ANF acts directly on epithelial cells of tubules where Na+ reabsorption occurs. This is in agreement with the hypothesis that ANF has a direct tubular effect on natriuresis.
Rambotti
M G
MG
Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy.
Saccardi
C
C
Spreca
A
A
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002462:Cell Membrane / Q000201:enzymology; D006162:Guanylate Cyclase / Q000032:analysis*; D006651:Histocytochemistry; D066298:In Vitro Techniques; D007668:Kidney / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D007672:Kidney Cortex / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D007679:Kidney Medulla / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D008297:Male; D009399:Nephrons / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000378:metabolism
C472610:atrial natriuretic peptide, rat; D009320:Atrial Natriuretic Factor; D012964:Sodium; D006162:Guanylate Cyclase