Possible modulation of process extension by N-methyl-D-aspartate receptor expressed in osteocytic MLO-Y4 cells

In contrast to osteoblasts,little attention has been paid to expression profiles of different glutamatergic signaling machineries in osteocytes,which are the most abundant cells with a possible role as a mechanical sensor in bone. here,we show that n-methyl-d-aspartate receptor (nmdar) is expressed by osteocytic cells in five-weeks-old mouse tibiae in vivo as well as by osteocytic mlo-y4 cells in vitro. sustained exposure to the nmdar antagonist dizocilpine significantly increased the number of cells with processes in cultured mlo-y4 cells. these results suggest that nmdar would be expressed by osteocytes with an unidentified role in the process extension. © the japanese pharmacological society.