The relationships between A) CRH hnRNA levels (an index of Crh transcription rates) and phosopho-ERK1/2 levels in the medial parvicellular part (mp) of the paraventricular nucleus of the hypothalamus (PVH); and B) plasma ACTH concentrations and phosopho-ERK1/2 levels in the PVHmp, 30 minutes after rats were exposed to either intravenous (iv) saline (open symbols) or insulin-induced hypoglycemia or iv 2-deoxy-D-glucose (solid symbols). Note the positive correlation (closed symbols, red lines) between CRH hnRNA and phospho-ERK1/2 (A), and ACTH and phospho-ERK1/2 in the stressed animals (B), but not in saline-injected control animals (open symbols, red lines). The dashed lines represents the positive correlations between both sets of variables across the full datasets. See Khan et al., 2011 for more detail. Data adapted from Khan et al., 2011, with permissions.