Inactivation of Oxytocin and its analogues by subcellular fractions of hen tissues.
The enzymic inactivation of oxytocin by liver, kidney, uterus and pancreas homogenate subcellular fractions of hens was studied. Oxytocin was most rapidly degraded by the soluble fraction of tissues examined. All the subcellular fractions of liver and kidney inactivated oxytocin, but only the microsomal and soluble fractions of uterus and pancreas showed the oxytocin-inactivating activity. The location of enzymes inactivating oxytocin in subcellular fractions of hen tissues was investigated with the aid of synthetic analogues of oxytocin (deamino-oxytocin and deamino-carba1-oxytocin). The carboxamidopeptidase activity, hydrolyzing the amide bonds in the linear portion of oxytocin was located in the soluble fraction of hen liver, kidney and uterus. No carboxamidopeptidase activity in the pancreatic soluble fraction was found. These results showed that aminopeptidase activity is bound to heavy subcellular particles in the hen tissue. An action of unknown endopeptidases was observed in the microsomal fraction of uterus and pancreas.
D000818:Animals; D002645:Chickens; D005260:Female; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D009928:Organ Specificity; D010121:Oxytocin / Q000031:analogs & derivatives* / Q000378:metabolism*; D010179:Pancreas / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism / Q000648:ultrastructure; D014599:Uterus / Q000378:metabolism
D010121:Oxytocin