Robberecht P, Waelbroeck M, De Neef P, Tastenoy M, Gourlet P, Cogniaux J, Christophe J
Department of Biochemistry and Nutrition, Medical School, Université Libre de Bruxelles, Belgium.
FEBS Lett. 1988 Feb 15;228(2):351-5. doi: 10.1016/0014-5793(88)80030-9.
A new type of VIP receptor was characterized in human SUP-T1 lymphoblasts. The order of potency of unlabeled peptides, in the presence of [125I]helodermin, was: helodermin(1-35)-NH2 = helodermin(1-27)-NH2 greater than helospectin greater than VIP = PHI greater than [D-Ser2]VIP greater than [D-Asp3]VIP greater than [D-His1]VIP greater than or equal to [D-Ala4]VIP greater than or equal to secretin = GRF. This specificity was distinct from that of all VIP receptors described so far in that: (i) the affinity for helodermin (Kd = 3 nM) was higher than that of VIP (Kd = 15 nM) and PHI (Kd = 20 nM); and (ii) position 4 played an important role in ligand binding. The labeled sites were likely to be functional receptors as adenylate cyclase in crude lymphoblastic membranes (200-10,000 x g pellets) was stimulated by peptides, in the presence of GTP, with the following order of potency: helodermin(1-35)-NH2 greater than helodermin(1-27)-NH2 greater than helospectin = VIP = PHI.
在人SUP-T1淋巴母细胞中鉴定出一种新型血管活性肠肽（VIP）受体。在[125I]海洛德明存在的情况下，未标记肽的效价顺序为：海洛德明（1 - 35）-NH2 = 海洛德明（1 - 27）-NH2 ＞ 海洛司肽 ＞ VIP = 胰高血糖素样肽（PHI）＞ [D - 丝氨酸2]VIP ＞ [D - 天冬氨酸3]VIP ＞ [D - 组氨酸1]VIP ≥ [D - 丙氨酸4]VIP ≥ 促胰液素 = 生长激素释放因子（GRF）。这种特异性与迄今为止描述的所有VIP受体不同，因为：（i）对海洛德明的亲和力（Kd = 3 nM）高于VIP（Kd = 15 nM）和PHI（Kd = 20 nM）；（ii）第4位在配体结合中起重要作用。标记位点可能是功能性受体，因为在GTP存在的情况下，粗淋巴细胞膜（200 - 10,000 x g沉淀）中的腺苷酸环化酶受到肽的刺激，其效价顺序为：海洛德明（1 - 35）-NH2 ＞ 海洛德明（1 - 27）-NH2 ＞ 海洛司肽 = VIP = PHI。
