Fig. 8.

Plasma corticosterone concentration as a function of plasma ACTH during Ringer’s (A) or VP antagonist (B) infusions at different times of the light/dark cycle. For the “novelty” experiment, values fromt = 15, 30, and 60 min samples were used. From the VP antagonist infusions, only the t = 30 values are displayed. Data from the Ringer’s infusions are derived also from thet = 30 samples, except the infusion at CT10, from which data from the t = 60 samples are also displayed. CT2 = ○; CT6 = ▵ (A) or ▴ (B); CT10 = ▪; CT14 = □; CT22 = ▿;novelty = ⋄.