Characterization of binding and receptors for epidermal growth factor in smooth muscle.
The mitogenic and differentiation-inducing activities of epidermal growth factor (EGF) in epithelial tissues have been well described. Since non-mitogenic effects of EGF, especially in mesenchymal tissues such as smooth muscle are not well-known (Nanney et al. 1984), we have examined EGF-binding and receptors in smooth muscle from many sites. Specific EGF binding sites were detected by incubating small pieces of tissue with 125I-EGF; immunoreactive EGF receptors were detected by immunohistochemistry. In-situ localization of 125I-EGF binding sites and immunoreactive EGF receptors of smooth muscle cells in intact mammalian tissues were identical using either 125I-EGF autoradiography or anti-EGF receptor antibody in an immunoperoxidase method. Cultured rat aortic smooth muscle also contained specific EGF receptors as detected by their biological response to EGF-binding and internalization of 125I-EGF, as well as EGF-stimulated phosphorylation of a 170K protein. The presence of EGF receptors in a well-differentiated smooth muscle cell indicates that EGF may play a physiological, but non-mitogenic role in mammalian tissues in vivo.
Nanney
L B
LB
Department of Plastic Surgery, Vanderbilt University, Nashville, Tennessee.
Stoscheck
C M
CM
King
L E
LE
D000818:Animals; D001345:Autoradiography; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D009130:Muscle, Smooth / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D010766:Phosphorylation; D011869:Radioligand Assay; D051381:Rats; D013552:Swine
D004815:Epidermal Growth Factor; D066246:ErbB Receptors