Fig. 5.

Cultures exposed to sublethal oxygen–glucose deprivation (OGD) exhibit increased AMPA/kainate-activated ⁴⁵Ca²⁺accumulation and AMPA-activated Δ [Ca²⁺]_i in neurons. A,⁴⁵Ca²⁺ accumulation during a 5 min exposure to 500 μm kainate or 300 μm AMPA in either sham-washed controls or cultures exposed to sublethal OGD 24 hr earlier (mean ± SEM; n = 8–14 cultures). Both kainate- and AMPA-activated ⁴⁵Ca²⁺accumulation were potentiated by sublethal OGD, and the kainate-induced potentiation was eliminated by 1 μm Joro spider toxin.B, Sublethal OGD also potentiated the increase in [Ca²⁺]_i evoked by a 15 sec exposure to 20 μm AMPA (mean ± SEM; n = 122–137 cells from 4 separate experiments). Basal [Ca²⁺]_i levels in neurons exposed to sublethal OGD were not different from those exposed to sham wash (data not shown). Asterisks indicate difference from respective sham-washed control at p < 0.05, using two-tailed Student’s t test.