小鼠脑中白三烯C4结合位点：药理学特性

Leukotriene C4 binding sites in mouse brain: pharmacological characteristics.

作者信息

Goffinet A, Nguyen A

机构信息

Positron Tomography Laboratory, University of Louvain, Louvain-la-Neuve, Belgium.

出版信息

Eur J Pharmacol. 1987 Aug 21;140(3):343-7. doi: 10.1016/0014-2999(87)90291-3.

DOI:10.1016/0014-2999(87)90291-3

PMID:2820764

Abstract

The binding sites for [3H]leukotriene C4 were studied in membrane preparations of mouse brain and liver. Isotherm binding analysis revealed one binding site with a Kd of 10.39 +/- 1.97 nM (Scatchard) or 10.15 +/- 1.00 nM (non-linear). The maximal binding capacity (Bmax) was 49.20 +/- 3.80 (Scatchard) or 48.50 +/- 2.63 (non-linear) pmol/mg prot. Specific binding represented more than 90% of the total binding. In displacement reactions on brain membranes, LTC4 was 100 times more active than LTD4, which displayed 10 times the activity of GSH. Glutamic acid, bilirubin and hematin were inactive. The activity of LTC4 was slightly less on liver membranes than on brain membranes. Liver sites had some affinity for GSH but not for LTD4 bilirubin or hematin. The results support the hypothesis that LTC4 and its receptor may have a neuromodulatory function.

摘要

在小鼠脑和肝的膜制剂中研究了[3H]白三烯C4的结合位点。等温线结合分析显示有一个结合位点，其解离常数（Kd）为10.39±1.97 nM（Scatchard法）或10.15±1.00 nM（非线性法）。最大结合容量（Bmax）为49.20±3.80（Scatchard法）或48.50±2.63（非线性法）pmol/mg蛋白。特异性结合占总结合的90%以上。在脑膜的置换反应中，白三烯C4的活性比白三烯D4高100倍，白三烯D4的活性是谷胱甘肽的10倍。谷氨酸、胆红素和血红素无活性。白三烯C4在肝膜上的活性略低于在脑膜上的活性。肝结合位点对谷胱甘肽有一定亲和力，但对白三烯D4、胆红素或血红素无亲和力。这些结果支持白三烯C4及其受体可能具有神经调节功能这一假说。