Hocher B, Dürr J A, Hensen J
Abteilung für Innere Medizin, Klinikum Steglitz, Freie Universität Berlin, Germany.
Eur J Clin Chem Clin Biochem. 1994 Feb;32(2):61-4. doi: 10.1515/cclm.1994.32.2.61.
We previously described a new iodinated vasopressin analogue (N epsilon-[125I]L-Tyr-[Lys8]-vasopressin) with high affinity for the vasopressin V1 and V2 isoreceptors. The aim of the present study was: i) to analyse the degradation pathway of N epsilon-[125I]L-Tyr-[Lys8]-vasopressin and (ii) to look for an effective inhibitor of radioligand degradation. N epsilon-[125I]L-Tyr-[Lys8]-vasopressin was processed in a temperature-dependent manner by crude cell membranes from LLC-PK1 cells. Only one degradation product was seen using RP-HPLC. The degradation product co-eluted with monoiodotyrosine. The stereoisomer, N epsilon-[125I]D-Tyr-[Lys8]-vasopressin, underwent the same degradation process. Bacitracin prevented degradation at doses as low as 40 mg/l without alterating the binding affinity.
我们之前描述了一种对血管加压素V1和V2异受体具有高亲和力的新型碘化血管加压素类似物（Nε-[125I]L-酪氨酸-[赖氨酸8]-血管加压素）。本研究的目的是：（i）分析Nε-[125I]L-酪氨酸-[赖氨酸8]-血管加压素的降解途径，以及（ii）寻找一种有效的放射性配体降解抑制剂。Nε-[125I]L-酪氨酸-[赖氨酸8]-血管加压素由LLC-PK1细胞的粗制细胞膜以温度依赖的方式进行处理。使用反相高效液相色谱法仅观察到一种降解产物。该降解产物与单碘酪氨酸共洗脱。立体异构体Nε-[125I]D-酪氨酸-[赖氨酸8]-血管加压素经历相同的降解过程。杆菌肽在低至40 mg/l的剂量下可防止降解，且不改变结合亲和力。
