Effects of CORT pretreatment on basal and stress-induced pituitary anterior lobe and intermediate lobe pomc hnRNA levels of non-CX or CX pretreated rats. (A) In the absence of CX pretreatment, restraint induced pomc hnRNA in the anterior pituitary. CORT pretreatment (1 h and 3 h) suppressed both basal and stress-induced pomc hnRNA levels. (B) Systemic CX pretreatment tended to increase basal, but not stress-induced pomc hnRNA in the anterior pituitary. CX blocked the suppressive effects of 3 h, but not 1 h CORT pretreatment on those measures. (C) In the absence of CX pretreatment, restraint induced pomc hnRNA in the intermediate lobe of the pituitary, and CORT pretreatment had no effect. (D) CX pretreatment had no significant effect on basal or stress-induced pomc hnRNA in the intermediate lobe of the pituitary. Panel E shows representative autoradiographic images of the pituitaries from key comparison conditions depicted in panels A–D. Values are presented as a percentage of the mean value of the non-CX pretreated stressed 3 h vehicle rats. *, represents a significant stress effect within same drug condition and pretreatment time point (p < 0.05, FLSD); +, represents a significant CORT effect compared to vehicle treated rats within the same pretreatment time and stress condition (p < 0.05, FLSD); R, represents a significant difference between CX pretreated rats (B) compared to the corresponding non-CX treated rats (A) (p < 0.05, FLSD).