Hypertonic saline and reduced peroxynitrite formation in experimental pancreatitis

OBJECTIVES: In this study, we tested the hypothesis that hypertonic saline exerts anti-inflammatory effects by modulating hepatic oxidative stress in pancreatitis. INTRODUCTION: The incidence of hepatic injury is related to severe pancreatitis, and hypertonic saline reduces pancreatic injury and mortality in pancreatitis. METHODS: Wistar rats were divided into four groups: control (not subjected to treatment), untreated pancreatitis (NT, pancreatitis induced by a retrograde transduodenal infusion of 2.5 percent sodium taurocholate into the pancreatic duct with no further treatment administered), pancreatitis with normal saline (NS, pancreatitis induced as described above and followed by resuscitation with 0.9 percent NaCl), and pancreatitis with hypertonic saline (HS, pancreatitis induced as described above and followed by resuscitation with 7.5 percent NaCl). At 4, 12, and 24 h after pancreatitis induction, liver levels of inducible nitric oxide synthase (iNOS), heat-shock protein 70, nitrotyrosine (formation of peroxynitrite), nitrite/nitrate production, lipid peroxidation, and alanine aminotransferase (ALT) release were determined. RESULTS: Twelve hours after pancreatitis induction, animals in the HS group presented significantly lower iNOS expression (P<0.01 vs. NS), nitrite/nitrate levels (P<0.01 vs. NS), lipid peroxidation (P<0.05 vs. NT), and ALT release (P<0.01 vs. NS). Twenty-four hours after pancreatitis induction, nitrotyrosine expression was significantly lower in the HS group than in the NS group (P<0.05). DISCUSSION: The protective effect of hypertonic saline was related to the establishment of a superoxide-NO balance that was unfavorable to nitrotyrosine formation. CONCLUSIONS: Hypertonic saline decreases hepatic oxidative stress and thereby minimizes liver damage in pancreatitis.

Efeito da solução hipertônica de NaCI 7, 5 por cento na resposta inflamatória em modelo de choque hipovolêmico / Effects of hypertonic solution (NaCI 7, 5 per cent) on the inflammatory response in an experimental model of hemorrhagic shock

A solução hipertônica de cloreto de sódio 7,5 por cento (SSH) é eficaz em restaurar os parâmetros hemodinâmicos e reduzir a inflamação em modelos experimentais de choque hemorrágico. Assim, foi nosso objetivo investigar a ação da SSH sobre os mecanismos envolvidos na lesão de isquemia e reperfusão (I/R) em um modelo de choque hemorrágico controlado. Ratos Wistar (280-350 g) foram submetidos à hemorragia controlada, mantendo-se a pressão arterial média em 40 mmHg por 1 h / Hypertonic saline solution (HSS - NaCI 7,5 per cent) was shown to restore hemodynamic parameters in hemorrhagic shock and to decrease the inflammation triggered by ischemia-reperfusion injury (I/R). Therefore, our objective was to investigate the effects of HSS on the mechanisms involved in I/R, in an experimental model of controled hemorrhagic shock. Wistar rats (2`80-350 g) were submitted to the controled bleeding, keeping the mean arterial pressure around 40 mmHg, for 1 hour...