GLAST expression on bullfrog Müller cells is regulated by dark/light.
Using immunofluorescence double-labeling, Western blotting and confocal laser scanning microscopy, we investigated if and how the expression of glial high-affinity glutamate/aspartate transporter (GLAST) in bullfrog Müller cells may be regulated by dark/light. Compared with light-adapted retinas, the expression of GLAST in Müller cells was overall up-regulated in retinas dark-adapted for 30 min but declined in retinas dark-adapted for longer (>30 min) periods. The declined expression level of GLAST during prolonged dark adaptation was raised by immersion with 1 mM glutamate. These results suggest that glutamate uptake mediated by GLAST could be regulated dynamically and efficiently in accord with dark/light-induced changes in glutamate release of retinal neurons.
Xu
Li-Ya
LY
Institute of Neurobiology, Institutes of Brain Science, Fudan University, 220 Handan Road, Shanghai 200433, China.
Zhao
Jing-Wei
JW
Yang
Xiong-Li
XL
D000221:Adaptation, Ocular / Q000502:physiology; D027322:Amino Acid Transport System X-AG / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D003624:Darkness; D004305:Dose-Response Relationship, Drug; D005455:Fluorescent Antibody Technique / Q000379:methods; D005786:Gene Expression Regulation / Q000187:drug effects / Q000528:radiation effects*; D018698:Glutamic Acid / Q000494:pharmacology; D008027:Light; D009836:Oligodendroglia / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D011892:Rana catesbeiana; D012160:Retina / Q000166:cytology*; D013997:Time Factors
D027322:Amino Acid Transport System X-AG; D018698:Glutamic Acid