Grosenbaugh D A, Amoss M S, Hood D M, Morgan S J, Williams J D
Department of Veterinary Physiology, College of Veterinary Medicine, Texas A&M University, College Station 77843.
Am J Physiol. 1988 Oct;255(4 Pt 1):C447-51. doi: 10.1152/ajpcell.1988.255.4.C447.
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.
在来自马胸主动脉的培养血管平滑肌细胞（VSMC）中研究了表皮生长因子（EGF）受体结合动力学以及EGF介导的DNA合成刺激和细胞增殖。使用鼠源125I标记的EGF进行的结合研究表明存在一类单一的高亲和力结合位点（表观KD = 2.8×10^(-11) M），估计最大结合容量为5800个位点/细胞。EGF以剂量依赖性方式刺激汇合静止单层中的[3H]胸苷摄取，在7.5×10^(-11) M时出现半最大刺激。同样，在降低的血清浓度下，EGF介导的细胞增殖是剂量依赖性的（50%有效剂量 = 5×10^(-11) M）。马VSMC含有EGF的特异性受体，并且EGF可以刺激这些培养细胞中的DNA合成和增殖，这表明EGF可能参与马远端指部外周血管疾病中观察到的增殖性变化。
