Apoptosis
The effect of nitric oxide on cell viability differs based on
the degree of redox stress; additionally, different cell types
differ considerably in their response to nitric oxide. In macrophages,
pancreatic islet cells, neurons, enterocytes, thymocytes, cardiac
myocytes, endothelial cells, and fibroblasts, even low level NO
lead to apoptosis. In contrast, B lymphocytes, natural killer
cells, eosinophils, embryonic motor neurons, pheochromocytomas,
ovarian follicles, and hepatocytes can be protected by NO against
apoptosis included in various ways. Hepatocytes are unique in
that not only are these cells protected by NO, but also necrotic
death is not seen until the cells are exposed to supraphysiologic
concentrations of NO donors in the millimolar range.
