Figure 4. Effects of unilateral injections of the GABA_A receptor antagonist bicuculline and the glycine receptor antagonist strychnine, in the PH nucleus of an alert cat during spontaneous eye movements.

Recordings of eye position in the horizontal (HP) and vertical (VP) planes after injections of the indicated drugs in the right PH nucleus, in either darkness (D) or light (L). Doses and times after injection were as follows: bicuculline, 1 nmol, 15 min (D) and 18 min (L); strychnine, 3.3 nmol, 8 min (D) and 9 min (L). Eye position is plotted in degrees (deg). Movement direction as indicated in Fig. 2. Slow phases for bicuculline and strychnine were best fitted to a linear equation, similar to slow phases after l-NAME injections.