Fig. 2.

LTD and its blockade by cPLA2α KO or inhibitors. (A) Averaged time course of LTD. Ordinate, rising slope of PF-EPSPs relative to the average of five measurements during the 5-min preconjunction period. Error bars attached either above or below the plotted points, SEM. 2PF, double-shock PF stimulation; md, membrane depolarization; 2PF + md, conjunction. In brackets, number of PCs included in the plot. Obliquely shaded band indicates period of conjunction. (Inset) Specimen records of PF-EPSPs obtained from a C57BL WT PC before and after conjunction (x, y). (B) Comparison of LTD induction between KO and littermate mice. (C) Ten-minute perfusion of pyrrolidine-1 at various times relative to conjunction. Horizontal bars indicate perfusion time. (D) LTD magnitude vs. perfusion time of pyrrolidine-1. Error bars in D as well as F represent SD. Horizontal broken line was determined under 0.01% DMSO perfusion for 20 min overlapping conjunction (24.3%). One-way ANOVA and Dunnett posthoc test show that open squares, not filled ones, deviate from the control line significantly at P < 0.01 (two sided). Double-headed arrow indicates time window in which cPLA₂α is involved in LTD. (E) Rescue of LTD by 5-min perfusion of 10 μM AA in cPLA₂α KO PCs. Two sets of data are plotted for 5-min AA perfusions overlapping or immediately following conjunction. (F) Rescuing effect of AA in cPLA₂α KO PCs. Horizontal broken line indicates LTD magnitude in cPLA2α KO PCs.