Oxytocin Affects Nitric Oxide and Cytokine Production by Sepsis-Sensitized Macrophages

Background/Aim: Oxytocin (OXT) secretion during cecal ligation puncture (CLP)-induced sepsis has not yet been examined. Although immune properties have been attributed to OXT, its effect on CLP-sensitized macrophages has never been investigated. We analyzed OXT secretion during CLP and its effect in CLP-sensitized macrophage cultures. Methods: Male Wistar rats were decapitated 4, 6 or 24 h after CLP surgery or sham operation and blood, brain and neurohypophyses were collected for OXT measurements. In another set of animals we studied the effect of OXT on nitrite, tumor necrosis factor (TNF-alpha), interleukin (IL)-1 beta and IL-10 production of peritoneal macrophages harvested at 6 and 24 h after CLP. Results: In the early phase of sepsis (4-6 h), OXT levels increased in plasma and decreased in hypothalamus and neurohypophysis. In the late phase (24 h), plasma and neurohypophyseal levels remained basal. In the paraventricular, the OXT content remained low, but in the supraoptic in-creased. Macrophages of the early phase of sepsis pretreated with OXT and stimulated with lipopolysaccharide showed decreased nitrite, TNF-alpha and IL-1 beta levels, but no alteration in IL-10 production. In the late phase, they showed reduction only on IL-1 beta. Conclusions: OXT secretion during sepsis may represent a neuroendocrine response contributing to the overall host response to infection by decreasing the proinflammatory response and oxidative stress. Copyright (C) 20125. Karger AG, Basel