Intranephron distribution of purine-metabolizing enzymes in rats.
The activities of purine-metabolizing enzymes, 5'-nucleotidase, adenosine deaminase, and purine nucleoside phosphorylase in microdissected rat nephron segments were measured. The specific activity of 5'-nucleotidase was highest in the proximal tubules and the cortical collecting duct, but low in the glomerulus. In contrast, the highest activity of adenosine deaminase was found in the glomerulus. The distribution pattern of purine nucleoside phosphorylase was similar to that of adenosine deaminase. These results suggest that various nephron segments can form adenosine and that the glomerulus exhibits highest capacities to metabolize this nucleoside.
Takahashi
T
T
Department of Pharmacology and Medicine, University of Tokyo, Japan.
Kakuno
K
K
Yamada
H
H
Endou
H
H
D015720:5'-Nucleotidase / Q000378:metabolism*; D000243:Adenosine Deaminase / Q000378:metabolism*; D000818:Animals; D007678:Kidney Glomerulus / Q000201:enzymology; D007685:Kidney Tubules, Collecting / Q000201:enzymology; D007686:Kidney Tubules, Distal / Q000201:enzymology; D007687:Kidney Tubules, Proximal / Q000201:enzymology; D008297:Male; D009399:Nephrons / Q000201:enzymology*; D009700:Nucleoside Deaminases / Q000378:metabolism*; D010430:Pentosyltransferases / Q000378:metabolism*; D011683:Purine-Nucleoside Phosphorylase / Q000378:metabolism*; D011687:Purines / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D011687:Purines; D010430:Pentosyltransferases; D011683:Purine-Nucleoside Phosphorylase; D015720:5'-Nucleotidase; D009700:Nucleoside Deaminases; D000243:Adenosine Deaminase