Figure 8

HPA axis function and placement controls. (A-C) To suppress HPA axis function rats were pretreated with dexamethasone (Dex, 0.05 mg/kg, subcutaneously) 2 hours prior to CRF administration into the CeLC [50, 51]. Injection of Dex had no significant (ns) effect on audible and ultrasonic vocalizations and spinal reflex thresholds measured 15 min before CRF administration (n = 6 rats). Administration of CRF (1 μM, concentration in the microdialysis probe; 15 min) into the CeLC following pretreatment with Dex had significant facilitatory effects (n = 5 rats). (D-F) Administration of CRF (1 μM, concentration in the microdialysis probe; 15 min) into the adjacent striatum as a placement control had no significant effect on vocalizations and reflex thresholds (n = 6). Bar histograms show means ± SEM. *,**,*** P < 0.05-0.001, compared to Dex alone; ns (not significant) P > 0.05, compared to predrug; Bonferroni posttests.