Figure 3.

TNF-α induces rapid insertion of new Ca-perm AMPAr receptors in membranes of adult MNs via a PI3K and PKA dependent mechanism.

A. Representative images: Acute lumbar spinal cord sections from 55–65 day old rats were subjected to kainate stimulated Co²⁺ uptake labeling, either alone, after incubation with 20 nM TNF-α, or in tissue that had been pretreated with the PI3K antagonist, wortmannin, or the PKA antagonist, H89, as described. Photomicrographs show ventral horn regions of Co²⁺ labeled sections from one experiment. Bar = 100 μm.

B. Quantitative assessment. After development of the Co²⁺ stain, staining intensity was quantified as described (see Materials and Methods). Data represent compilation of 6 experiments comprising TNF-α and control conditions, with H89 and wortmannin each included in 3 (with >600 MNs counted each condition). * indicates difference from the control, TNF-α+H89 and TNF-α+wortmannin (p<0.02) by Kruskal-Wallis one way ANOVA on ranks with Student-Newman-Keuls post hoc test.