Figure 2.
(A) Injection regimen used to determine the duration of GABAA receptor activation necessary to induce a phase delay. All groups received a series of 4 hourly injections into the SCN region between CT13.5 and CT16.5. However, the number of consecutive injections containing muscimol (21.9mM) varied from 0 to 4 (VEH = vehicle; MUS = muscimol). (B) Mean±SE of phase delays produced by the 5 treatments outlined in A (* vs. 0 muscimol injections, p=0.002). (C) Injection regimen used to determine whether a single injection of muscimol at CT 16.5 might induce a phase delay or whether a single injection equal to the cumulative dose of 4 individual injections of muscimol might induce a phase delay. Animals in the 0.0 mM group received 4 hourly injections of vehicle into the SCN region between CT13.5 and CT16.5. Animals in the 21.9 and 87.6mM groups received 3 consecutive hourly injections of vehicle followed 1 hour later by a single injection of 21.9mM or 87.6mM muscimol into the SCN region (VEH = vehicle; MUS = muscimol). (D) Mean±SE of phase delays produced by the 3 treatments outlined in C.