Desflurane differentially affects the release of proinflammatory cytokines in plasma and bronchoalveolar fluid of endotoxemic rats

Abstract

Previous studies have indicated that volatile anaesthetics can attenuate the inflammatory response to lipopolysaccharide (LPS) and other proinflammatory stimuli in vitro and in vivo. Thus far, no studies are available on the influences of desflurane on the cytokine-release. We therefore aimed to investigate the effects of desflurane on the systemic and pulmonary release of proinflammatory cytokines in endotoxemic rats. Eighteen anaesthetized and ventilated Sprague-Dawley rats were randomly assigned to the following groups: LPS-only: Six animals received LPS (5 mg/kg, i.v.) with no further intervention. LPS-Desflurane: Six animals received continuous inhalation of 1MAC Desflurane before and during endotoxemia with LPS (5 mg/kg, i.v.). Sham: Six animals served as control without inhalation of desflurane and endotoxemia. After 4 h, levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) in plasma and bronchoalveolar fluid were analyzed. Nitrite production as a readout for nitric oxide (NO) release from alveolar macrophages was measured by Griess assay. IkappaB-alpha degradation and iNOS-protein in macrophage homogenates were determined by Western Blotting. Inhalation of desflurane during endotoxemia showed a significant decrease in release of the proinflammatory cytokines TNF-alpha (-61%, P< or =0.05) and IL-1beta (-47%, P< or =0.05) in plasma as compared to LPS-only group, whereas the release of IL-6 was not significantly affected by desflurane. Within the lung, the NO-release was notably increased in supernatants of cultured alveolar macrophages from desflurane-group compared to both LPS-only and Sham group. IkappaB-alpha degradation in alveolar macrophages was impaired in the Desflurane-group as compared to the LPS-only group. Our data implicate that inhalation of 1MAC Desflurane during experimental endotoxemia differentially affects the inflammatory response in rats.