Fate of circulating isoamylases in the rabbit.
Amylase purified from the pancreas and parotid gland of rabbits was labeled with 125I. Plasma disappearance was biexponential after bolus injection. Half-time of metabolic clearance was 97 and 95 min, respectively, for pancreatic and salivary 125I-amylase. About 20 and 30% of the injected pancreatic and salivary 125I-amylase, respectively, appeared intact in the urine within 24 h. Organs were assayed for radioactivity at specified times. No organ at any time contained more than 20% of injected radioactivity. At 24 h, more than 90% of radioactivity in organs was acid soluble. Bilateral nephrectomy significantly slowed plasma disappearance, although 90% hepatectomy did not. These studies in the rabbit indicate that 1) homologous isoamylases are cleared from plasma at rates comparable with those reported in primates; 2) in contrast to primates, urinary excretion of salivary amylase is greater than pancreatic amylase; and 3) within 24 h, virtually all of injected 125I-labeled isoamylases were catabolized or excreted.
D000681:Amylases / Q000097:blood* / Q000302:isolation & purification; D000818:Animals; D006498:Hepatectomy; D007527:Isoenzymes / Q000097:blood* / Q000302:isolation & purification; D007700:Kinetics; D008297:Male; D009392:Nephrectomy; D009928:Organ Specificity; D010179:Pancreas / Q000201:enzymology; D011817:Rabbits; D012463:Saliva / Q000201:enzymology
D007527:Isoenzymes; D000681:Amylases