12 research outputs found
Distinct Expression/Function of Potassium and Chloride Channels Contributes to the Diverse Volume Regulation in Cortical Astrocytes of GFAP/EGFP Mice
Recently, we have identified two astrocytic subpopulations in the cortex of GFAP-EGFP mice, in which the astrocytes are visualized by the enhanced greenâfluorescent protein (EGFP) under the control of the human glial fibrillary acidic protein (GFAP) promotor. These astrocytic subpopulations, termed high response- (HR-) and low response- (LR-) astrocytes, differed in the extent of their swelling during oxygen-glucose deprivation (OGD). In the present study we focused on identifying the ion channels or transporters that might underlie the different capabilities of these two astrocytic subpopulations to regulate their volume during OGD. Using three-dimensional confocal morphometry, which enables quantification of the total astrocytic volume, the effects of selected inhibitors of K+ and Clâ channels/transporters or glutamate transporters on astrocyte volume changes were determined during 20 minute-OGD in situ. The inhibition of volume regulated anion channels (VRACs) and two-pore domain potassium channels (K2P) highlighted their distinct contributions to volume regulation in HR-/LR-astrocytes. While the inhibition of VRACs or K2P channels revealed their contribution to the swelling of HR-astrocytes, in LR-astrocytes they were both involved in anion/K+ effluxes. Additionally, the inhibition of Na+-K+-Clâ co-transporters in HR-astrocytes led to a reduction of cell swelling, but it had no effect on LR-astrocyte volume. Moreover, employing real-time single-cell quantitative polymerase chain reaction (PCR), we characterized the expression profiles of EGFP-positive astrocytes with a focus on those ion channels and transporters participating in astrocyte swelling and volume regulation. The PCR data revealed the existence of two astrocytic subpopulations markedly differing in their gene expression levels for inwardly rectifying K+ channels (Kir4.1), K2P channels (TREK-1 and TWIK-1) and Clâ channels (ClC2). Thus, we propose that the diverse volume changes displayed by cortical astrocytes during OGD mainly result from their distinct expression patterns of ClC2 and K2P channels
Reduced lung endothelial angiotensin-converting enzyme activity in Watanabe hyperlipidemic rabbits in vivo
Intravenous Lacosamide in Refractory Seizure Clusters and Status Epilepticus: Comparison of 200 and 400Â mg Loading Doses.
The treatment of refractory status epilepticus (RSE) remains largely empirical. Lacosamide (LCM) is a new anticonvulsant available in intravenous (IV) form, but its optimal dosing regimen for the treatment of RSE is unknown. We compared safety and efficacy of two loading doses: 200 and 400Â mg.JOURNAL ARTICLESCOPUS: ar.jinfo:eu-repo/semantics/publishe