Activation of the hypothalamic-pituitary-adrenal (HPA) axis and augmented plasma and tissue levels of interleukin-6 (IL-6) are hallmarks of heart failure (HF). Within the forebrain, cardiovascular homeostasis is mediated in part by the paraventricular nucleus (PVN) of the hypothalamus. IL-6, via binding to the interleukin-6 receptor (IL-6R) / glycoprotein 130 (gp130) complex influences cellular and physiological responses. Thus, in the current study we hypothesized that PVN IL-6R protein and gene expression are up-regulated in HF versus sham-operation rats while gp130 levels in the same tissues remain stable. Six weeks following coronary ligation surgery hemodynamic measurements were obtained and HF rats were divided into moderate noncongestive and severe chronic congestive groups based on cardiac indices. Plasma IL-6 levels were determined and changes in gene and protein expression of IL-6R and gp130 between sham-operation and HF rats were determined via real-time PCR and western blot analyses respectively. Plasma levels of IL-6 were elevated in rats with severe but not moderate HF when compared to sham-operation controls. In both moderate and severe HF rats, protein but not gene expression of IL-6R was significantly increased in PVN tissue, but not in non-PVN tissue, when compared to sham-operation controls. Gene and protein levels of the gp130 subunit were not altered by HF in either tissue analyzed. Collectively, these data suggest that within the brain of HF rats, IL-6R expression is not a global change. Rather the increased IL-6 levels characteristic of HF may alter PVN-mediated physiological responses via enhanced expression of the IL-6R.