Muscimol nearly abolishes spontaneous activity in cortical, VRC, and NTS neurons. A: mean normalized firing rate is shown for cortical neurons in slices from SA (n = 4; n = 52 neurons; open circles) and IBA squirrels (n = 4; n = 73 neurons, solid circles) in response to 20 μM muscimol (applied at vertical line). IBA time controls are shown (n = 4; n = 22 neurons, gray circles). B: mean normalized firing rate is shown for VRC neurons in slices from SA (n = 4; n = 12 neurons; open squares) and IBA squirrels (n = 4; n = 54 neurons; solid squares). IBA time controls are shown (n = 4; n = 40 neurons, gray squares). C: mean normalized firing rate is shown for NTS neurons in slices from SA (n = 4; n = 48 neurons, open triangles) and IBA squirrels (n = 4; n = 41 neurons; solid triangles). IBA time controls are shown (n = 4; n = 12 neurons, gray triangles). After a 60-min drug application, neuronal activity was nearly abolished in all neurons (†P < 0.05). Error bars indicate means ± SE.