Epidermal growth factor-mediated effects on equine vascular smooth muscle cells.
Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125I-labeled EGF, indicate the presence of a single class of high-affinity binding sites (apparent KD = 2.8 X 10(-11) M), with an estimated maximal binding capacity of 5,800 sites/cell. EGF stimulated [3H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 X 10(-11) M. Likewise, EGF-mediated cellular proliferation was dose dependent (50% effective dose = 5 X 10(-11) M) under reduced serum concentrations. Equine VSMC contain specific receptors for EGF, and EGF can stimulate DNA synthesis and proliferation in these cultured cells, which suggests that EGF may participate in the proliferative changes observed in equine distal digital peripheral vascular disease.
Grosenbaugh
D A
DA
Department of Veterinary Physiology, College of Veterinary Medicine, Texas A&M University, College Station 77843.
Amoss
M S
MS
Hood
D M
DM
Morgan
S J
SJ
Williams
J D
JD
D000818:Animals; D001011:Aorta; D001667:Binding, Competitive; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media; D004261:DNA Replication / Q000187:drug effects; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D066246:ErbB Receptors / Q000378:metabolism*; D006734:Horse Diseases / Q000378:metabolism; D006736:Horses; D007700:Kinetics; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D014652:Vascular Diseases / Q000662:veterinary
D003470:Culture Media; D004815:Epidermal Growth Factor; D066246:ErbB Receptors