R. Beckmann et al., BRADYKININ INDUCES RISE OF FREE CALCIUM IN NUCLEI OF NEUROBLASTOMA X GLIOMA HYBRID NG-108-15 CELLS, Journal of neuroscience research, 40(5), 1995, pp. 571-578
Confocal fluorescence microscopy was used to study the bradykinin-indu
ced calcium signals in the neuroblastoma x glioma cell line NG 108-15.
We found that bradykinin induced a rise in free calcium, not only in
the cytoplasm but also in the nucleus, The nuclear and cytosolic calci
um concentrations were not significantly different and rose to about 1
.2 mu M. The signal was mediated by the B-2-receptor subtype as confir
med using the specific antagonist Hoe 140. Both the onset and the inte
nsity of the calcium signals were concentration-dependent. The rise of
nuclear calcium level was independent of extracellular calcium and su
ppressed by thapsigargin which is known to deplete inositol 1,4,5-tris
phosphate-sensitive calcium stores, Bradykinin-induced calcium increas
e desensitizes rapidly, This desensitization was shown not to involve
activation of protein kinase C. (c) 1995 Wiley-Liss, Inc.