Glutamate receptor and transporter modifications in rat organotypic hippocampal slice cultures exposed to oxygen-glucose deprivation: The contribution of cyclooxygenase-2

Meloxicam is a non-steroidal anti-inflammatory drug which has been reported to lessen the ischemic transcriptional effects in some of the glutamatergic system genes as well as to decrease the infarct volume in in vivo assays. In this study we show how the presence of meloxicam decreases the cell mortality in assays of oxygen- glucose deprivation (OGD) in rat organotypic hippocampal slices culture. Mortality was measured by using propidium iodide. Transcript levels of some glutamatergic system genes, including vesicular and membrane glutamate transporters (VGLUT1, VGLUT2, GLAST-1A, GLT-1, and EAAC) and some glutamatergic receptor subunits (NMDA receptor GluN1, GluN2A and GluN2B subunits and AMPA GluA1 and GluA2 subunits) were measured by real time PCR (qPCR). The transcription of vesicular glutamate transporters and glutamatergic receptor subunits, but not membrane glutamate transporters, was modified by the presence of meloxicam. The study demonstrates the neuroprotective role of meloxicam in organotypic hippocampal slice cultures and it is shown how meloxicam is able to selectively increase or decrease the OGD-induced changes in the expression of the different glutamatergic system genes here studied. We suggest that the neuroprotective role of meloxicam could be due to a modification in the balance of the expression of some glutamatergic receptor subunits, leading to a different stoichiometry of receptors such as NMDA or AMPA. Thus, meloxicam would decrease the excitotoxicity induced by OGD.