Fig. 3.

Rate-meter histograms showing impulse activity of striatal neurons and their responses to GLU (short open box) and DA (long open box) after administration of SCH-23390 (SCH). DA and GLU were tested both on spontaneously active and GLU-stimulated units (line below histogram). Numbers below iontophoretic applications indicate ejection current in nanoamperes, no numbers in subsequent applications indicate the same current as the last indicated application. In all cases, neuronal activity is presented as impulses/2 sec, and each division on the ordinate of all histograms represents 20 impulses/2 sec. Solid lines below each histogram indicate periods of overt movement; at all other times, the animals were at quiet rest. The histological location of individual recordings in dorsal (NC) and ventral striatum (NAcc) and their numbers (rat, session, and unit, respectively) are identified in the top right corner of each histogram. Arrows above DA tests indicate significant DA-induced decreases (↓) and increases (↑) in activity;no arrows indicate no response. Trianglesshow cases of GLU-induced depolarization inactivation with rate values (impulses per second) immediately preceding the cessation of firing. In the top three examples, SCH was administered in the middle of the recording, but in all other cases, the antagonist was injected before the recording began (numbers above these histograms to the left indicate time in minutes after SCH).