Figure 5.
Endogenous glutamate acting on mGluRs significantly contributes to spontaneous calcium dynamics in the developing neocortex. (A) A subset of neurons exhibiting spontaneous, oscillatory calcium dynamics (approximately 40%) continues to display these calcium dynamics in the presence of TTX (1 μM), DNQX (10 μM), and d-AP5 (100 μM). Subsequent coapplication of the group I-specific mGluR antagonist S-4-CPG blocks this remaining spontaneous oscillatory activity. (B) The near abolition of spontaneous [Ca2+]i transients in the presence of S-4-CPG is quantified (n = 7 slices, >200 active cells before S-4-CPG; ∗, P ≪ 0.001, Student’s t test).