D by A2ARs (Fig. 1, compare A, D). Ouabain brought on a
D by A2ARs (Fig. 1, compare A, D). Ouabain brought on a bimodal but parallel effect around the activities of each NKA (Fig. 2A) and of glutamate transporters (Fig. 2B) in cortical gliosomes. Therefore, a low ouabain concentration (0.1 M) induced a 40.0 five.0 enhance (n 4, p 0.05) of NKA activityResultsActivation of A2ARs decreases NKA activity in gliosomes Considering that A2ARs control the uptake of glutamate by the astrocytic glutamate transporters GLT-I (Matos et al., 2012b) and the efficiency of glutamate transporters depend on the sodium gradientMatos et al. A2A Receptor Controls Na K -ATPaseJ. Neurosci., November 20, 2013 33(47):184928502 Figure 1. Activation of A2ARs leads to a selective reduce with the activities of both NKA and glutamate transporters in gliosomes but not in synaptosomes from either the cerebral cortex or striatum. Gliosomes and synaptosomes from brain cortex or striatum were incubated with out or with all the A2AR-selective agonist CGS 21680 (30 00 nM) andor antagonist SCH 58261 (50 nM). A, The activation of A2ARs by CGS 21680 in cortical gliosomes (open symbols) reduces NKA activity, whereas it increases NKA activity in synaptosomes (closed symbols). B, C, These opposite effects of CGS 21680 (100 nM) on NKA activity have been prevented by SCH 58261 in cortical gliosomes and synaptosomes (B) and in striatal gliosomes (C). D, E, The activation of A2ARs with CGS 21680 (30 00 nM) inhibited [ 3H]D-aspartate uptake both in cortical gliosomes and in synaptosomes (D) and SCH 58261 prevented this impact of CGS 21680 (100 nM; E). F, A2AR activation by CGS 21680 (100 nM) also inhibited [ 3H]D-aspartate uptake in striatal gliosomes, whereas no substantial effects were observed in striatal synaptosomes. NKA activity was determined by subtracting the total ATPase activity in the ATPase activity inside the presence of membrane ATPase inhibitor ouabain and was expressed as micromole Pi liberated from ATP by 1 g of protein ( mol Pi g protein), whereas the precise uptake of [ 3H]D-aspartate was calculated by subtracting the uptake activity in the uptake activity inside the presence of Na -free buffer NMG and was expressed as nanomoles of [ 3H]D-aspartate retained per milligrams of gliosome protein per minute. Animal-Free IFN-gamma, Mouse (His) Information are imply SEM of at the least three independent experiments completed in triplicate. Statistical differences have been gauged applying the Tukey’s post hoc test applied just after one-way ANOVA with p 0.05 and p 0.01, when compared with nontreated conditionspared with nontreated gliosomes, in agreement with earlier reports (Lichtstein et al., 1985; Gao et al., 2002; Antolovic, 2006) along with a lowmoderate concentration of ouabain (1 M) had no impact on NKA activity. Meanwhile, moderatehigher concentrations (10 00 M) inhibited NKA activity (n 4, p 0.05), and also a larger concentration (2 mM) of ouabain triggered a 73.0 11.two inhibition (n 4, p 0.01) of NKA activity (Fig. 2A). In CCN2/CTGF, Human (HEK293) accordance using the crucial NKA-mediated handle of GLT-I activ-ity, a low ouabain concentration (0.1 M) improved [ 3H]Daspartate uptake by 26.1 4.1 (n four, p 0.05), a low moderate concentration (1 M) had no effect on [ 3H]D-aspartate uptake, a moderatehigher concentration (10 M) inhibited (n four, p 0.05) [ 3H]D-aspartate uptake, plus a larger concentration (two mM) inhibited [ 3H]D-aspartate uptake by 75.0 9.0 (n four, p 0.001; Fig. 2B), as previously observed (Pellerin and Magistretti, 1997; Rose et al., 2009).18496 J. Neurosci., November 20, 2013 33(47):18492Matos et al. A2A Receptor Controls Na K -ATPaseWe next analyzed.