Figure 4.

Graphs showing the effects of NGF or CytC on NMDA- and AMPA-evoked NOS activity in the rat hippocampus. Samples were collected bilaterally every 20 min, and l-[¹⁴C]citrulline was measured in the effluent. The values of the last samples after equilibration were designated as baseline (100%) at time zero (0) on both sides, and all other values were expressed as percentages of these values. Expressed in this manner, the baseline values did not differ significantly from the values of the previous three samples. Immediately after the samples were collected at time 0, the dialysis perfusates were switched to either NMDA or AMPA (1 mM) alone on one side, and to either NMDA+NGF or AMPA+NGF (0.01 μg/μl) on the other side. Both NMDA (n = 7) and AMPA (n = 7) induced sustained and statistically significant increases in l-[¹⁴C]citrulline recovery as compared with baseline values (P < 0.05). In contrast, simultaneous delivery of NGF with NMDA (n = 7) or AMPA (n = 6) did not significantly alter l-[¹⁴C]citrulline recovery as compared with baseline values. (ANOVA, with Sidak’s posthoc pairwise comparison)