Background: Roles of astrocytes in the modulatory effects of oxytocin (OT) in central nervous system are increasingly considered. Nevertheless, OT effects on gliotransmitter release have been neglected.
Methods: In purified astrocyte processes from adult rat striatum, we assessed OT receptor (OTR) and adenosine A2A receptor expression by confocal analysis. The effects of receptors activation on glutamate release from the processes were evaluated; A2A-OTR heteromerization was assessed by co-immunoprecipitation and PLA. Structure of the possible heterodimer of A2A and OT receptors was estimated by a bioinformatic approach.
Results: Both A2A and OT receptors were expressed on the same astrocyte processes. Evidence for A2A-OTR receptor-receptor interaction was obtained by measuring the release of glutamate: OT inhibited the evoked glutamate release, while activation of A2A receptors, per se ineffective, abolished the OT effect. Biochemical and biophysical evidence for A2A-OTR heterodimers on striatal astrocytes was also obtained. The residues in the transmembrane domains 4 and 5 of both receptors are predicted to be mainly involved in the heteromerization.
Conclusions: When considering effects of OT in striatum, modulation of glutamate release from the astrocyte processes and of glutamatergic synapse functioning, and the interaction with A2A receptors on the astrocyte processes should be taken into consideration.
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http://dx.doi.org/10.3390/ijms23042326 | DOI Listing |
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Department of Pharmaceutical Sciences and Center for Blood-Brain Barrier Research, Jerry H. Hodge School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, Texas, USA.
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Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
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Molecules
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Department of Chemistry & Chemical Biology, The University of New Mexico, Albuquerque, NM 87131, USA.
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Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720.
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View Article and Find Full Text PDFFASEB J
January 2025
Department of Eye Center, Xiangya Hospital, Central South University, Changsha, China.
Fatty acid binding proteins (FABPs) are a class of small molecular mass intracellular lipid chaperone proteins that bind to hydrophobic ligands, such as long-chain fatty acids. FABP5 expression was significantly upregulated in the N-methyl-d-aspartic acid (NMDA) model, the microbead-induced chronic glaucoma model, and the DBA/2J mice. Previous studies have demonstrated that FABP5 can mediate mitochondrial dysfunction and oxidative stress in ischemic neurons, but the role of FABP5 in oxidative stress and cell death in retina NMDA injury models is unclear.
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