Expression of iNOS gene in macrophages stimulated with 17β-estradiol is regulated by free intracellular Ca2+
Citations Over TimeTop 22% of 2004 papers
Abstract
17Beta-estradiol has potent Ca2+ ionophore capability and its signaling in macrophages is mediated through binding to surface and genomic receptors, resulting in transient nitric oxide (NO) elaboration. We decided to examine if the transient release of NO is due to Ca2+ influx pattern or the quenching effect of superoxide (*O2-) through peroxynitrite formation. Differential chelation of intracellular Ca2+ ([Ca2+]i) showed that NO generation was favored by [Ca2+]i concentration of 237 nM. Application of an estrogen receptor antagonist ICI 182 780 resulted in attenuation of estradiol mediated NO release. Studies directed at identifying the possible role of *O2-; in the attenuation of NO showed no supportive evidence. Inhibition of extracellular Ca2+ channel or extracellular and intracellular Ca2+ channels showed data consistent with a case for optimum Ca2+ influx signal favoring iNOS gene expression, accompanied by an elevation in iNOS protein. These data show that Ca2+ influx pattern determines macrophage NO elaboration.
Related Papers
- → Labile intracellular zinc is associated with 3T3 cell growth(2001)33 cited
- → Possible coexistence of two independent mechanisms contributing to anthracycline resistance in leukaemia P388 cells(1993)15 cited
- → Radiosensitizer-DNA interactions in relation to intracellular uptake(1989)21 cited
- → Intracellular Na+ and Ca2+ activities in aortic smooth muscle cells from spontaneously hypertensive rats(1982)7 cited
- Intracellular pH of the turtle bladder assessed with fluorescent probes.(1987)