ABSTRACT
Beyond the regulation of cardiovascular function, baroreceptor afferents play polymodal roles. We hypothesized that baroreceptor denervation affects lipopolysaccharide (LPS)-induced systemic inflammation (SI) and hemodynamic collapse in conscious rats, and that these parameters are interconnected. We combine: a) hemodynamic and thermoregulatory recordings after LPS administration at a septic-like dose b) analysis of the cardiovascular complexity, c) evaluation of vascular function in mesenteric resistance vessels, and d) measurements of inflammatory cytokines (plasma and spleen). LPS-induced drop in blood pressure was higher in sino-aortic denervated (SAD) rats. LPS-induced hemodynamic collapse was associated with SAD-dependent autonomic disbalance. LPS-induced vascular dysfunction was not affected by SAD. Surprisingly, SAD blunted LPS-induced surges of plasma and spleen cytokines. These data indicate that sino-aortic afferents are key to alleviate LPS-induced cardiovascular collapse, affecting the autonomic cardiovascular control, without affecting resistance blood vessels. Moreover, baroreflex modulation of the LPS-induced SI and hemodynamic collapse seem not to be interconnected.
