SUMMARY
We studied the regulation of n-methy-d-aspartate receptor (NMDAR) current/activation by glutamate transporter type 3 (EAAT3), a neuronal EAAT in vivo, in the restricted extracellular space of a biological model. This model involved co-expressing EAAT3 and NMDAR (composed of NMDAR1-1a and NMDAR2A) in Xenopus oocytes. The NMDAR current was reduced in the co-expression oocytes but not in oocytes expressing NMDAR only when the flow of glutamate-containing superfusate was stopped. The degree of this current reduction was glutamate concentration-dependent. No reduction of NMDAR current was observed in Na+-free solution or when NMDA, a non-substrate for EAATs, was used as the agonist for NMDAR. In the continuous flow experiments, the dose-response curve of glutamate-induced current was shifted to the right-hand side in co-expression oocytes compared with oocytes expressing NMDAR alone. The degree of this shift depended on the abundance of EAAT3 in the co-expression oocytes. Thus, the glutamate concentrations sensed by NMDAR locally were lower than those in the superfusates. These results suggest that EAAT3 regulates the amplitude of NMDAR currents at pre-saturated concentrations of glutamate to EAAT3. Thus, EAATs, by rapidly regulating glutamate concentrations near NMDAR, modulate NMDAR current/activation.
- © The Company of Biologists Limited 2005
Article navigation
Related articles
Cited by...
More in this TOC section
Similar articles
Other journals from The Company of Biologists
JEB and COVID-19
We are aware that the COVID-19 pandemic is having an unprecedented impact on researchers worldwide. The Editors of all The Company of Biologists’ journals have been considering ways in which we can alleviate concerns that members of our community may have around publishing activities during this time. Read about the actions we are taking at this time.
Please don’t hesitate to contact the Editorial Office if you have any questions or concerns.
Announcing JEB's 2019 Outstanding Paper Prize
Congratulations to all of the authors whose papers were shortlisted for the 2019 JEB Outstanding Paper Prize. This year we had a great selection of papers and the final winners were Kephra Beckett and Anne Roberts, from the University of British Columbia, Canada, for their work on spittlebug breathing in xylem sap foam.
The Biology Open transfer option
JEB authors have the option to transfer their submission to our sister journal Biology Open. An online Open Access journal, BiO also welcomes direct submissions and focuses on the swift publication of high-quality, sound research. Recent comparative physiology highlights in BiO include the current cover article from Okuyama et al., who show that Green sea turtles have an immediate cardiac response to exercise during submergence. Find out more about how to transfer.
Mantis shrimp pull punches in air for self-preservation
In their new Short Communication, Feller et al. demonstrate that punches by mantis shrimp in air are slower and only one tenth of the power than in thick water.
What determines systemic blood flow in vertebrates?
To understand how systemic blood flow is regulated, Tobias Wang and William Joyce look at factors beyond the heart in their new Review.
JEB appoints new Editor-in-Chief
We are delighted to announce that Craig Franklin (University of Queensland, Australia) has been appointed as the next EiC of JEB, starting on 1 August. With research interests in animal ecophysiology and conservation physiology, Craig is already familiar with the journal, having been a Monitoring Editor since 2011. We are looking forward to welcoming him in his new role.