Rosenbach T, Liesegang C, Binting S, Czarnetzki B M
Universitäts-Hautklinik, Klinikum Rudolf Virchow, Freie Universität, Berlin, Germany.
Arch Dermatol Res. 1993;285(7):393-6. doi: 10.1007/BF00372131.
Phospholipase C-mediated release of inositol trisphosphate, followed by an increase in free intracellular calcium, is an important signal transduction pathway for several membrane receptors. In the present investigation, the coupling of various receptors to phospholipase C was studied in the human keratinocyte line HaCaT. Inositol trisphosphate formation was determined by anion-exchange chromatography, and the release of intracellular calcium was analysed with the fluorescence probe Fura-2 AM. Activation of HaCaT keratinocytes with bradykinin resulted in a time- and dose-dependent release of inositol trisphosphate and intracellular calcium, with an EC50 value of 50 nM for bradykinin-induced inositol trisphosphate formation. The mediators and cytokines IL-1, IL-4, IL-6, IL-8, EGF and TGF alpha, as well as bombesin, prolactin, carbachol, substance P and retinoic acid, did not activate this pathway. The inability of the mediators examined to activate phospholipase C may be due to lack of the respective cognate receptors or to the use of other signal transduction pathways.
磷脂酶C介导的肌醇三磷酸释放，随后细胞内游离钙增加，是几种膜受体重要的信号转导途径。在本研究中，在人角质形成细胞系HaCaT中研究了各种受体与磷脂酶C的偶联。通过阴离子交换色谱法测定肌醇三磷酸的形成，并用荧光探针Fura-2 AM分析细胞内钙的释放。用缓激肽激活HaCaT角质形成细胞导致肌醇三磷酸和细胞内钙的时间和剂量依赖性释放，缓激肽诱导的肌醇三磷酸形成的EC50值为50 nM。介质和细胞因子IL-1、IL-4、IL-6、IL-8、EGF和TGFα，以及蛙皮素、催乳素、卡巴胆碱、P物质和视黄酸，均未激活该途径。所检测的介质未能激活磷脂酶C可能是由于缺乏相应的同源受体或使用了其他信号转导途径。
