Involvement of AA in the inhibition of astrocyte GJC induced by costimulation of neuronal NMDA and muscarinic receptors studied by scrape-loading in cocultures. (A) The astrocyte uncoupling induced by NMDA + Carb or NMDA + ACh (100 μM and 1 mM, respectively, 15 min) was reversed by treatment of the cocultures with mepacrine (Mep; 50 μM, 20-min pretreatment), BSA (5 mg/ml), or indomethacin (Indo; 10 μM, 30-min pretreatment), but not by nordihydroguaiaretic acid (NDGA; 5 μM, 30-min pretreatment). (B) Effects of either NDGA or indomethacin on the inhibition of astrocyte GJC induced by exogenous AA (5 μM, 15 min) in cocultures. Analysis were carried out from 3 to 25 independent experiments. Statistical significance of treatments, when compared to the effect of NMDA + Carb or ACh (A) or to control (B), were established by one-way ANOVA followed by post hoc Dunnett's multiple comparison.