title: Serum proline imino-peptidase activity in normal adult subjects and in patients with Paget's disease of bone.
abstract: The activity of proline imino-peptidase (EC 3.4.1.4) may provide a measure of collagen degradation, and a method for its estimation in human serum is described. The mean value of this enzyme activity in 48 normal adults of 4.7 mU/l (S.D. 0.9) did not change with sex, age or dietary collagen. In 8 patients with liver disease associated with elevated levels of plasma alkaline phosphatase activity the mean value was normal (4.5 mU/l, S.D. 1.5). However, in 25 patients with untreated Paget's disease of bone, values were significantly increased (mean 7.4 mU/l; S.D. 2.8; p less than 0.001) and were positively correlated with plasma alkaline phosphatase activity (r = 0.75; p less than 0.001) and with urine total hydroxyproline excretion (r = 0.68; p less than 0.001). In patients given disodium ethane-1-hydroxy-1,1-diphosphonate for 3--6 months, serum proline imino-peptidase activity decreased to normal values.
mesh_terms: D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D000626:Aminopeptidases / Q000097:blood*; D004044:Dietary Proteins / Q000378:metabolism; D012968:Etidronic Acid / Q000627:therapeutic use; D005260:Female; D005780:Gelatin / Q000378:metabolism; D006801:Humans; D006909:Hydroxyproline / Q000652:urine; D008107:Liver Diseases / Q000201:enzymology; D008297:Male; D008875:Middle Aged; D010001:Osteitis Deformans / Q000201:enzymology*; D011392:Proline
chemical_list: D004044:Dietary Proteins; D005780:Gelatin; D011392:Proline; D000469:Alkaline Phosphatase; D000626:Aminopeptidases; D012968:Etidronic Acid; D006909:Hydroxyproline