کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1939260 | 1050757 | 2006 | 7 صفحه PDF | دانلود رایگان |
Calcium is a ubiquitous second messenger controlling a broad range of cellular functions. We previously observed that N,N-dimethyl-d-ribo-phytosphingosine (DMPH) and lysophosphatidylcholine (LPC) induced Ca2+ influx across the plasma membrane in U937 monocytes. In this study, we characterized the Ca2+ influx induced by DMPH and LPC. L-type voltage-gated Ca2+ channel blockers, verapamil and nifedipine, significantly reduced LPC-induced Ca2+ influx, but not DMPH-induced one. On the other hand, non-specific Ca2+ channel blockers, Ga3+ and La3+, considerably reduced DMPH- and LPC-induced Ca2+ influx. Preincubation of the cells with forskolin enhanced DMPH-induced Ca2+ influx, however, LPC-induced Ca2+ influx was not affected by the treatment. The enhancement by forskolin was blocked by KT5720, a PKA inhibitor. We also confirmed the presence of TRPM7 and absence of TRPM3 in U937 cells. Therefore, our characterization of Ca2+ influx in U937 human monocytes shows the presence of two different types of Ca2+ channels modulated by lysolipid molecules, DMPH and LPC. LPC may induce Ca2+ influx via L-type Ca2+ channels and DMPH seems to induce Ca2+ influx through TRPM7 in U937 human monocytes.
Journal: Biochemical and Biophysical Research Communications - Volume 348, Issue 3, 29 September 2006, Pages 1116–1122