Values are mean ± SEM. n = 10 cells.R_input was determined by measuring the sustained current deflection during a voltage step from −80 to −90 mV. mEPSCs were measured over a 200 sec continuous interval before any additional manipulation (depolarization or quisqualate application). Bis-fura-2 microfluorimetric measurements of depolarization-evoked and quisqualate-evoked Ca were conducted in cells separate from those of the LTD experiments. Values are peak proximal dendritic Ca concentration for Purkinje neurons and peak somatic Ca for granule neurons. Depolarization-evoked Ca_i was measured in cells that were incubated in normal (2 mm Ca-containing) external saline and stimulated with a 3 sec depolarizing pulse from −80 to 0 mV. Quisqualate-evoked Ca_i, a measure of group I mGluR function, was measured in cells that were incubated in 0 Ca/0.2 EGTA external saline and stimulated with a pressure pulse of 100 μm quisqualate (dissolved in 0 Ca/0.2 EGTA saline, 4 psi, 2 sec). This pressure pulse delivered agonist to the entire cell. Resting values were measured immediately before stimulation. Depolarization-evoked values were measured as the peak during a 30 sec measuring period after the onset of depolarization, and quisqualate-evoked values were measured as the peak during a 120 sec measuring period after the onset of the pressure pulse.

↵* p < 0.01 compared with WT, Student'st test.