Fold change in ACTH secretion (mean ± SEM) after CRH, AVP, or CRH + AVP administration in the NCR (white bars) and CR (gray bars) groups in the absence of C-TOX treatment. The horizontal dashed line denotes no increase in secretion over basal rates. +P < 0.05, CR vs. NCR groups; #P < 0.05, CRH + AVP vs. CRH or AVP alone.