Insulin-like growth factor receptors in testicular vascular tissue from normal and diabetic rats.
Testicular blood vessels contain IGF-I and IGF-II/M6P receptors. Binding to these receptors was altered following treatment with streptozotocin to induce diabetes. Intensity of labelling and size of receptors were examined using SDS-gel electrophoresis and autoradiography. The IGF-I and IGF-II/M6P receptor of the diabetic rat testicular microvessels appear to have a lower molecular weight as compared to controls. Macro- and microvascular tissues from diabetic rats apparently contain more IGF-I receptors than normal Sprague-Dawley rats. Using immunohistochemical techniques, the IGF-II/M6P receptor appears to dissociate easier from diabetic rat testicular arteries than from control animal blood vessels. M6P appears to increase both IGF-I and IGF-II binding to the rat IGF-II/M6P receptor, at least as visualized using affinity crosslinking analysis. Whether these differences in the IGF receptors are involved in the development of diabetic vascular disease is not yet known.
Haskell
J F
JF
Department of Obstetrics and Gynecology, University of Alabama, Birmingham.
Myers
R B
RB
D000818:Animals; D002352:Carrier Proteins / Q000032:analysis; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D007150:Immunohistochemistry; D018969:Insulin-Like Growth Factor Binding Proteins; D008297:Male; D008833:Microcirculation / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000032:analysis*; D017451:Receptors, Somatomedin; D012016:Reference Values; D013002:Somatomedins / Q000096:biosynthesis*; D013737:Testis / Q000098:blood supply* / Q000378:metabolism
D002352:Carrier Proteins; D018969:Insulin-Like Growth Factor Binding Proteins; D011956:Receptors, Cell Surface; D017451:Receptors, Somatomedin; D013002:Somatomedins