Roca B, Arilla E, Prieto J C
Regul Pept. 1986 Feb;13(3-4):273-81. doi: 10.1016/0167-0115(86)90045-5.
Specific binding sites for somatostatin have been identified in cytosolic fraction of rabbit kidney (cortex and outer medulla) using 125I-Tyr11-somatostatin. The binding was saturable and reversible, as well as time and temperature dependent. Optimal pH for binding was observed at about 7.4. Scatchard plots were compatible with the existence of two classes of binding sites: a first class with a high affinity (Kd = 40 nM) and a low binding capacity (2.0 pmol somatostatin/mg protein) and a second class with a low affinity (Kd = 222 nM) and a high binding capacity (114.3 pmol somatostatin/mg protein). Vasoactive intestinal peptide, neurotensin, substance P, Leu-enkephalin and vasopressin had practically no effect on somatostatin binding. The properties of these binding sites strongly support the concept that somatostatin could behave as a regulatory peptide on the rabbit kidney.
利用¹²⁵I-酪氨酸¹¹-生长抑素，在兔肾（皮质和外髓质）的胞质组分中鉴定出了生长抑素的特异性结合位点。该结合具有饱和性和可逆性，且与时间和温度相关。观察到结合的最佳pH约为7.4。Scatchard图与两类结合位点的存在相符：第一类具有高亲和力（Kd = 40 nM）和低结合容量（2.0 pmol生长抑素/毫克蛋白质），第二类具有低亲和力（Kd = 222 nM）和高结合容量（114.3 pmol生长抑素/毫克蛋白质）。血管活性肠肽、神经降压素、P物质、亮氨酸脑啡肽和加压素对生长抑素结合几乎没有影响。这些结合位点的特性有力地支持了生长抑素可能作为兔肾调节肽的概念。
