FIGURE 6.

Classical CaMKII inhibitors prevent AKAP79-anchored PKC regulation of GluA1. A, HEK cells were transfected with GluA1 ± AKAP79. A summary time course of GluA1 receptor currents is shown, demonstrating that AKAP79 facilitates PKC regulation of GluA1 (GluA1 AKAP79 versus GluA1 + AKAP79 + PKM, p < 0.05). PKM (4 nm) was included in the patch pipette as indicated. All data are expressed as mean ± S.E. The number of observations for each condition is indicated. Insets, representative glutamate-evoked (500-ms) current traces from the first (black) and final (red) sweep (10 min) for each condition. Vertical scale bars equal 500 pA. B, KN-62 and KN-93, but not KN-92 or CaMKIINtide, inhibit AKAP79-anchored PKC regulation of GluR1 (KN-62 and KN-93 both p < 0.05 compared with GluA1 + AKAP79 + PKM from A). Cells were transfected with GluA1 + AKAP79. Patch pipettes contained PKM. Cells were pretreated with KN-62, KN-93, KN-92, or CaMKIINtide and recorded in the continued presence of these reagents. Data are depicted as in A except that vertical scale bars equal 1 nA. C, buffering CaM by infusion of the CaMBD (10 μm) restores AKAP79-anchored PKC-mediated up-regulation of GluA1 receptor currents in the presence of KN-62 and KN-93. Cells were transfected with GluA1 + AKAP79. Cells were infused with the CaMBD alone or the CaMBD + PKM in the presence of KN-62 or KN-93. Data are depicted as in A except that vertical scale bars equal 1 nA. The CaMBD alone did not modify the stability of GluR1 receptor currents (compare with GluA1 + AKAP79 in A). However, infusion of the CaMBD prevented KN-62- and KN-93-mediated inhibition of AKAP79-anchored PKC regulation of GluA1 (both p < 0.05 compared with the corresponding treatments in B).