Figure 4.

AMPAR-mediated ROS generation is enhanced by low extracellular pH. A, B. Cortical cultures were loaded with HEt, and exposed for 5 min to 300 μM kainate and washed for 50 min with a buffer at pH 7.4 (A) or pH 6.2 (B). HEt fluorescence changes for each neuron are expressed as the ratio of fluorescence at each time point (F_x) to its own baseline fluorescence (F₀). Traces show mean (± SEM) of 29 (A) or 40 (B) neurons from 3 experiments. C. Bar graph depicts the cumulative ROS production as area under the curve during the recovery phase in the two conditions, * indicates differences between washout at pH 7.4 versus washout at pH 6.2 (P < 0.01) Note the marked increase in HEt fluorescence only in the case of kainate exposures followed by an acidotic wash out.