Effects of inhalation of isoflurane on plasma and pulmonary levels of IL-1β and IL-10 in rats

Objective To investigate the effects of inhalation of isoflurane (Iso) on pulmonary and systemic inflammatory response through the changes in the plasma and pulmonary levels of IL-1β and IL-10 in rats. Methods Thirty-two adult male Wistar rats were randomly divided into 4 groups (n=8 each): group control (group C), group Iso-4 h, group Iso-8 h and group R. Group C inhaled air only. Group Iso-4 h and Iso-8 h inhaled in 40% O2 + 1.5% Iso for 4 and 8 h respectively. Group R inhaled 40% O2 + 1.5% Iso for 8 h and then withdrew and only inhaled 40 % O2 for 2 h. Blood samples were taken from femoral artery for measurement of plasma concentrations of IL-1β and IL-10 by ELISA. Then the rots were sacrificed to collect bronchoalveolar lavage fluid (BALF) for measurement of IL-1β and IL-10 concentrations. The right lung tissues were obtained for determination of the expression of IL-1β mRNA and IL-10 mRNA by RT-PCR. Results The BALF concentration of IL-1β and IL-1β mRNA expression in lung tissues were significantly higher in group Iso-4 h, and the concentrations of plasma and BALF IL-1β and IL-10, and the expression of IL-1β mRNA and IL-10 mRNA in lung tissues were significantly higher in group Iso-8 h than in group C (P 0.05). The plasma and BALF IL-10 concentrations and IL-10 mRNA expression in lung tissues were significantly higher in group Iso-8 h than in group Iso-4 h (P<0.05). The concentrations of plasma and BALF IL-1β and IL-10 and expression of IL-1β mRNA and IL-10 mRNA in lung tissues were significantly lower in group R than in group Iso-8 h (P<0.05). Conclusion Isollurane inhalation can induce transient pulmonary and systemic inflammatory response in rats. Key words: Isoflurane; Administration,inhalation; Interleukins; Sepsis syndrome