García-Sevilla J A, Escribá P V, Busquets X, Walzer C, Guimón J
Department of Psychiatry, Medical School, University of Geneva, Switzerland.
Neuroreport. 1996 Dec 20;8(1):169-72. doi: 10.1097/00001756-199612200-00034.
The newly discovered imidazoline receptors have been found to be upregulated in patients with major depression (platelet 45 kDa and 35 kDa proteins) and in suicide victims (brain 45 kDa protein). The signalling pathways coupled to these receptors are not known however. The aim of this study was to quantify, in platelets of depressed patients, the density of various G proteins to assess possible associations with the abundance of imidazoline proteins. There were positive correlations between the immunoreactivities of 45 kDa imidazoline receptors and those of G alpha q/11 (r = 0.64, n = 19, p < 0.005), G alpha i2 (r = 0.46, n = 22, p < 0.05) and G beta (r = 0.62, n = 18, p < 0.01) proteins. The relationship with regulatory G alpha q/11 proteins suggests that this 45 kDa protein (putative I1 imidazoline receptor) may couple to phosphoinositide pathway in platelets. This finding might be of relevance in understanding the functional implications of the abnormal higher expression of imidazoline receptors (45 kDa protein) in the pathogenesis of major depression.
新发现的咪唑啉受体在重度抑郁症患者（血小板中的45 kDa和35 kDa蛋白）及自杀受害者（大脑中的45 kDa蛋白）中呈上调状态。然而，与这些受体偶联的信号通路尚不清楚。本研究的目的是在抑郁症患者的血小板中量化各种G蛋白的密度，以评估其与咪唑啉蛋白丰度之间可能存在的关联。45 kDa咪唑啉受体的免疫反应性与Gαq/11（r = 0.64，n = 19，p < 0.005）、Gαi2（r = 0.46，n = 22，p < 0.05）和Gβ（r = 0.62，n = 18，p < 0.01）蛋白的免疫反应性之间存在正相关。与调节性Gαq/11蛋白的关系表明，这种45 kDa蛋白（推定的I1咪唑啉受体）可能在血小板中与磷酸肌醇途径偶联。这一发现可能与理解咪唑啉受体（45 kDa蛋白）异常高表达在重度抑郁症发病机制中的功能意义相关。
