Figure 6.

ON-MC LTD does not require activation of AMPA or NMDA receptors and is antagonized by the mGluR antagonist MCPG. A, Time course of ON Ca²⁺ signals in control saline and in the presence of 40 μm NBQX and 50 μm d-APV (APV) with and without tetanization. B, Bath application of 1 mm MCPG (black bar; n = 14) had no effect on test fEPSPs but depressed the expression of ON-MC LTD compared with control (n = 14). C, Bath application of 1 mm MCPG (black bar; n = 14) had no effect on baseline Ca²⁺ signals but depressed the reduction of the ON Ca²⁺ signals during ON-MC LTD compared with control (n = 14). The arrows represent the time of tetanization. Error bars represent SEM.