Moody T W, Mahmoud S, Staley J, Naldini L, Cirillo D, South V, Felder S, Kris R
Department of Biochemistry, George Washington University School of Medicine, Washington, DC 20037.
J Mol Neurosci. 1989;1(4):235-42.
Bombesin/gastrin-releasing peptide receptors were characterized in human glioblastoma cell lines. [125I]Gastrin-releasing peptide or ([125I]Tyr4)bombesin bound with high affinity to these cell lines. Binding to cell line U-118 was time dependent, reversible, and specific. ([125I]Tyr4)Bombesin bound with high affinity (Kd = 1.6 nM) to a single class of sites (Bmax = 30,000/cell). The C-terminal of bombesin- or gastrin-releasing peptide was essential for high-affinity binding. Bombesin- or gastrin-releasing peptide elevated the cytosolic Ca2+ levels in a dose-dependent manner. Because gastrin-releasing peptide, but not gastrin-releasing peptide, increased the cytosolic Ca2+ levels, the C-terminal but not the N-terminal of GRP is essential for biological activity. These data indicate that biologically active bombesin receptors are present in human glioblastoma cell lines.
蛙皮素/胃泌素释放肽受体在人胶质母细胞瘤细胞系中得到了表征。[125I]胃泌素释放肽或([125I]Tyr4)蛙皮素与这些细胞系具有高亲和力结合。与U - 118细胞系的结合具有时间依赖性、可逆性且具有特异性。([125I]Tyr4)蛙皮素以高亲和力（Kd = 1.6 nM）与单一类别的位点结合（Bmax = 30,000/细胞）。蛙皮素或胃泌素释放肽的C末端对于高亲和力结合至关重要。蛙皮素或胃泌素释放肽以剂量依赖性方式升高胞质Ca2+水平。由于胃泌素释放肽（而非促胃液素释放肽）可升高胞质Ca2+水平，因此GRP的C末端而非N末端对于生物活性至关重要。这些数据表明具有生物活性的蛙皮素受体存在于人胶质母细胞瘤细胞系中。
