Preventive effects of dexmedetomidine on the liver in a rat model of acid-induced acute lung injury.

The aim of this study was to examine whether dexmedetomidine improves acute liver injury in a rat model. Twenty-eight male Wistar albino rats weighing 300-350 g were allocated randomly to four groups. In group 1, normal saline (NS) was injected into the lungs and rats were allowed to breathe spontaneously. In group 2, rats received standard ventilation (SV) in addition to NS. In group 3, hydrochloric acid was injected into the lungs and rats received SV. In group 4, rats received SV and 100 µg/kg intraperitoneal dexmedetomidine before intratracheal HCl instillation. Blood samples and liver tissue specimens were examined by biochemical, histopathological, and immunohistochemical methods. Acute lung injury (ALI) was found to be associated with increased malondialdehyde (MDA), total oxidant activity (TOA), oxidative stress index (OSI), and decreased total antioxidant capacity (TAC). Significantly decreased MDA, TOA, and OSI levels and significantly increased TAC levels were found with dexmedetomidine injection in group 4 (P < 0.05). The highest histologic injury scores were detected in group 3. Enhanced hepatic vascular endothelial growth factor (VEGF) expression and reduced CD68 expression were found in dexmedetomidine group compared with the group 3. In conclusion, the presented data provide the first evidence that dexmedetomidine has a protective effect on experimental liver injury induced by ALI.