Figure 3.

Effect of 100ng of D-Phe-CRH in mPFC on ACTH and corticosterone responses to acute or repeated stress. Plasma ACTH and plasma corticosterone responses to the first restraint (acute restraint) or to the eighth restraint (repeated restraint) are shown in rats that received intra-mPFC injections of 100ng of D-Phe-CRH or VEH prior to day 1 or 8 of restraint. (The following are sample sizes at each time point of the ACTH response. For acute vehicle, n=11 at 0, 15 and 30 min, and n=10 at 60 min. For acute drug, n=10 at 0 min and 15 min, n=7 at 30 min, and n=9 at 60 min. For repeated vehicle, n=10 at 0 min and 15 min, n=7 at 30 min, n=9 at 60 min. Lastly, for repeated drug, n=10 at 0 min, n=9 at 15 min, n=8 at 30 min, and n=10 at 60 min. The following are sample sizes at each time point of the corticosterone response. For acute vehicle, n=9 at 0 min, n=11 at 15 min, n=8 at 30 min, and n=10 at 60 min. For acute drug, n=7 at all time points. For repeated vehicle, n=11 at 0 min and 15 min, and n=9 at 30 min and 60 min. Lastly, for repeated drug, n=7 at 0 min, and n=10 at 15 min and 30 min, and n=11 at 60 min.)

* D-Phe-CRH-injected groups are significantly lower than vehicle-injected groups regardless of whether animals were acutely or repeatedly stressed, reflecting a significant Main effect of Drug Treatment, p ≤ 0.05.

** Repeatedly stressed groups are significantly lower than acutely stressed groups regardless of drug treatment, reflecting a significant Main effect of Stress Group, p ≤ 0.05.