Abstract
p38 Mitogen-activated protein kinase (p38 MAPK) is one of the MAP kinase families, and supposed to play significant roles in survival of mature neuronal cells. In developing mouse brain, however, the localizations and roles of p38 remain unclear. In the present study, we performed Western blot analysis and immunohistochemical analysis of developing mouse brain using antibody against p38 MAPK. p38 MAPK was preferentially expressed in the brain from embryonic 11th day (E11) to E18 rather than that from postnatal 8 weeks. In the E10-E14 brain, most of the p38 MAPK-positive cells were located in the subventricular zone, and were positive for nestin, but not beta III tubulin. To ascertain the roles of p38 MAPK on early embryonic brain cells, the cultured cells were exposed to selective chemical inhibitors of p38 MAPK (SB202190 or SB203580) for 7 days. These inhibitors increased the number of neurosphere, and intracellular amount of ATP. In addition, similar results were obtained by using nestin-positive neural progenitor cells generating from seceondary neurosphere. These results suggest that p38 MAPK could involve in the proliferation and/or survival of neural progenitor cells in developing mouse brain. [J Physiol Sci. 2007;57 Suppl:S142]
