@misc{oai:kumadai.repo.nii.ac.jp:00026973,
 author = {Lu, Mei-Hong and 呂, 美紅},
 month = {Sep},
 note = {application/pdf, 学位論文(Thesis), Sphingomyelin (SM), a major species of sphingolipids, is a ubiquitous component of
cell membranes and plays vital roles in signal transduction and cell growth and survival.
However, its physiological functions have not been fully elucidated. Here we have
examined the role of SM synthesis mediated by SM synthase (SMS) family members,
SMS1 and SMS2, in auditory function. Hearing ability of SMS1 null mice, assessed
with an association learning experiment and with auditory brainstem response, was
impaired, especially at low frequency range; the impairment was accompanied by
abnormalities of stria vascularis (SV), i.e., a decrease in the width of SV and a
disorganization of marginal cells. Further, fluorescent immunostaining and western
blotting revealed an altered expression pattern and reduced level of KCNQ1 channels in
marginal cells. In addition, SMS1 knockout (KO) mice exhibited a significant decrease
of endocochlear potential and distortion product otoacoustic emissions, suggesting the
defects of cochlear functions. And observation of more macrophage invasion into SV at
apical region than other regions may explain the low frequency hearing loss in these
SMS1 KO mice. Mice lacking SMS2, however, showed no detectable hearing loss.
Taken together, our results suggest hearing impairment in SMS1 deficient mice but not
in SMS2 deficient mice. Defects in SV may at least in part account for the hearing
impairment in SMS1 deficient mice.},
 title = {Hearing impairment in SMS1 deficient mice},
 year = {2012}
}