Selective protamine sulphate inactivation of lipoprotein lipase and hepatic lipase in human post-heparin plasma: specific lipase levels in normals and in type I hyperlipoproteinaemia.
The rate of inactivation of triglyceride hydrolase activity by protamine sulphate was determined in pooled, normal, post-heparin plasma. Two distinct first-order rates of inactivation were obtained and the derived constants used to calculate the lipoprotein lipase and hepatic lipase contributions to the total post-heparin triglyceride hydrolase activity in normal controls and in patients with familial hyperchylomicronaemia. The lipoprotein lipase was reduced in the patients whereas the hepatic lipase was normal. There was however a marked age-related increase in the hepatic enzyme activity in normal subjects. Post-heparin lipolytic activity, assayed in vitro against lipoproteins of d less than 1.006 derived from the patients, was markedly reduced in our hyperchylomicronaemic subjects. This assay correlated well with the lipoprotein lipase activity determined by selective protamine sulphate inactivation.
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002914:Chylomicrons / Q000097:blood*; D005260:Female; D006493:Heparin / Q000494:pharmacology*; D006801:Humans; D006867:Hydrolases / Q000037:antagonists & inhibitors / Q000097:blood; D006949:Hyperlipidemias / Q000097:blood* / Q000235:genetics*; D007223:Infant; D008049:Lipase / Q000037:antagonists & inhibitors / Q000097:blood*; D008071:Lipoprotein Lipase / Q000037:antagonists & inhibitors / Q000097:blood*; D008099:Liver / Q000201:enzymology*; D008297:Male; D011479:Protamines / Q000494:pharmacology; D012016:Reference Values; D014280:Triglycerides / Q000097:blood*
D002914:Chylomicrons; D011479:Protamines; D014280:Triglycerides; D006493:Heparin; D006867:Hydrolases; D008049:Lipase; D008071:Lipoprotein Lipase