TLR4 and Rigidity: Here it has been found that also adipose tissue expresses the neuropeptide CRH as part of the inflammatory response (Section Inflammation and Arterial Rigidity), together with in the immune system toll-like receptor-4 (TLR4), the production of inflammatory cytokines IL-6, TNFα and IL-1β, chemokine IL-8, monocyte attractant protein-1 (MCP-1), and of the adipokines adiponectin, resistin, and leptin (Dermitzaki et al., 2014).