Superoxide radicals induce LTP in STTn and LTD in GABAn, but hydroxyl radicals are important only for GABAn-LTD. (A and B) Induction of STTn-LTP (n=5, N=5) and GABAn-LTD (n=5, N=5) by a superoxide radical donor (KO2, 1 mM). (C and D) Induction of GABAn-LTD (D, n=5, N=5) but not STTn-LTP (C, n=5, N=5) by a hydroxyl radical donor (tBOOH, 1 mM). ROS donors were superfused into the recording chamber for 10 min (thick black bar) after 3 min of baseline EPSC measurements. All data were obtained from adult 4 weeks old mice.