Decrease in serum receptor-reactive somatomedin in diabetes.
Somatomedin in rat serum has been measured by a sensitive radioreceptor assay using 125I-labelled human somatomedin and human placental membrane. In rats made diabetic with strepotzotocin, receptor-reactive somatomedin levels were decrease by up to 75%. The decrease followed the time course of increasing serum glucose and occurred to the same extent in rats aged between 4 and 40 weeks. Endogenous serum receptor-reactive somatomedin appeared exclusively in high molecular weight fractions on gel chromatography. In diabetes the decreased somatomedin was due to a fall in this high molecular weight activity, but was not accompanied by a fall in somatomedin binding protein. These results suggest a role for insulin in maintaining serum somatomedin levels.
D000818:Animals; D001681:Biological Assay; D001786:Blood Glucose / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000097:blood*; D005260:Female; D006801:Humans; D007700:Kinetics; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism; D013002:Somatomedins / Q000097:blood*; D013311:Streptozocin / Q000494:pharmacology
D001786:Blood Glucose; D011956:Receptors, Cell Surface; D013002:Somatomedins; D013311:Streptozocin