TY - JOUR
T1 - Cellular localization of facilitated glucose transporter 1 (GLUT-1) in the cochlear stria vascularis
T2 - Its possible contribution to the transcellular glucose pathway
AU - Ando, Motonori
AU - Edamatsu, Midori
AU - Fukuizumi, Sho
AU - Takeuchi, Shunji
N1 - Funding Information:
This study was supported by a grant-in-aid for scientific research (19570058) from The Ministry of Education, Culture, Sports, Science, and Technology of Japan. M.Ando(*).M.Edamatsu.S.Fukuizumi Laboratory of Cell Physiology, Department of Science Education, Okayama University, Okayama 700-8530, Japan e-mail: andom@cc.okayama-u.ac.jp
PY - 2008/3
Y1 - 2008/3
N2 - Immunoreactivity for the facilitated glucose transporter 1 (GLUT-1) has been found in the cochlear stria vascularis, but whether the strial marginal cells are immunopositive for GLUT-1 remains uncertain. To determine the cellular localization of GLUT-1 and to clarify the glucose pathway in the stria vascularis of rats and guinea pigs, immunohistochemistry was performed on sections, dissociated cells, and whole-tissue preparations. Immunoreactivity for GLUT-1 in sections was observed in the basal side of the strial tissue and in capillaries in both rats and guinea pigs. However, the distribution of the positive signals within the guinea pig strial tissue was more diffuse than that in rats. Immunostaining of dissociated guinea pig strial cells revealed GLUT-1 in the basal cells and capillary endothelial cells, but not in the marginal cells. These results indicated that GLUT-1 was not expressed in the marginal cells, and that another isoform of GLUT was probably expressed in these cells. Three-dimensional observation of whole-tissue preparations demonstrated that cytoplasmic prolongations from basal cells extended upward to the apical surface of the stria vascularis from rats and guinea pigs, and that the marginal cells were surrounded by these protrusions. We speculate that these upward extensions of basal cells have been interpreted as basal infoldings of marginal cells in previous reports from other groups. The three-dimensional relationship between marginal cells and basal cells might contribute to the transcellular glucose pathway from perilymph to intrastrial space.
AB - Immunoreactivity for the facilitated glucose transporter 1 (GLUT-1) has been found in the cochlear stria vascularis, but whether the strial marginal cells are immunopositive for GLUT-1 remains uncertain. To determine the cellular localization of GLUT-1 and to clarify the glucose pathway in the stria vascularis of rats and guinea pigs, immunohistochemistry was performed on sections, dissociated cells, and whole-tissue preparations. Immunoreactivity for GLUT-1 in sections was observed in the basal side of the strial tissue and in capillaries in both rats and guinea pigs. However, the distribution of the positive signals within the guinea pig strial tissue was more diffuse than that in rats. Immunostaining of dissociated guinea pig strial cells revealed GLUT-1 in the basal cells and capillary endothelial cells, but not in the marginal cells. These results indicated that GLUT-1 was not expressed in the marginal cells, and that another isoform of GLUT was probably expressed in these cells. Three-dimensional observation of whole-tissue preparations demonstrated that cytoplasmic prolongations from basal cells extended upward to the apical surface of the stria vascularis from rats and guinea pigs, and that the marginal cells were surrounded by these protrusions. We speculate that these upward extensions of basal cells have been interpreted as basal infoldings of marginal cells in previous reports from other groups. The three-dimensional relationship between marginal cells and basal cells might contribute to the transcellular glucose pathway from perilymph to intrastrial space.
KW - Basal cell
KW - Confocal laser microscopy
KW - Glucose transporter
KW - Guinea pig
KW - Inner ear
KW - Marginal cell
KW - Rat (Brown Norway)
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U2 - 10.1007/s00441-007-0495-2
DO - 10.1007/s00441-007-0495-2
M3 - Article
C2 - 18196278
AN - SCOPUS:39149109590
VL - 331
SP - 763
EP - 769
JO - Zeitschrift für Zellforschung und mikroskopische Anatomie (Vienna, Austria : 1948)
JF - Zeitschrift für Zellforschung und mikroskopische Anatomie (Vienna, Austria : 1948)
SN - 0302-766X
IS - 3
ER -