Reflex control of inflammation by the splanchnic anti-inflammatory pathway is sustained and independent of anesthesia

Abstract

Following an immune challenge, there is two-way communication between the nervous and immune systems. It is proposed that a neural reflex—the inflammatory reflex—regulates the plasma levels of the key proinflammatory cytokine TNF-α, and that its efferent pathway is in the splanchnic sympathetic nerves. The evidence for this reflex is based on experiments on anesthetized animals, but anesthesia itself suppresses inflammation, confounding interpretation. Here, we show that previous section of the splanchnic nerves strongly enhances the levels of plasma TNF-α in conscious rats 90 min after they received intravenous LPS (60 μg/kg). The same reflex mechanism, therefore, applies in conscious as in..