Pain behavior and spinal cell activation due to carrageenan-induced inflammation in two inbred rat strains with differential hypothalamic-pituitary-adrenal axis reactivity

► HPA axis reactivity and inflammatory vulnerability differ in Fischer and Lewis rats. ► One day after inflammation Fischer rats display an enhanced nociceptive sensitivity. ► Lewis rats are more sensitive in ongoing inflammatory conditions. ► FosB/ΔFosB-labeling remains greater in Fischer rats one week after inflammation. ► At this time Lewis rats exhibit greater microglial activation.