Effects of isoflurane on lung surfactant protein A in rats / 北京大学学报(医学版)

ABSTRACT

Objective:To examine the effects of different concentrations of Isoflurane on the level of surfactant protein A(SP-A) and the expression of SP-A mRNA in the lung of rats.Methods: Thirty-two male Wistar rats were randomly divided into 4 groups control group received 40%(volume fraction) O_2 inhalation(40% O_2,n=8);0.7% isoflurane group(n=8),1.5% isoflurane group(n=8).They and 2.0% isoflurane group(n=8).They were treated with 40%O_2 with 0.7%,1.5% and 2.0% isoflurane respectively.In each group,the rats inhaled experimental gas for 8 hours,and then were put to death immediately.Morphological changes of type Ⅱ pneumocytes were observed by transmission electron microscopy.Surfactant protein content in broncho-alveolar lavage fluid(BALF) was measured with Western Blotting.The level of intracellular SP-A was examined with immunohistochemistry(IHC).To assess the relative levels of SP-A mRNA in lung tissue,reverse transcriptase-polymerase chain reaction(RT-PCR) was used with the co-amplification of the "housekeeping" gene GAPDH as internal control.Results: Morphological changes of type Ⅱ pneumocytes were distinct in 1.5% isoflurane and 2.0% isoflurane groups.Isoflurane,after three doses,significantly reduced the SP-A content in BALF.Control group,(437 112)?25 654;0.7%Isoflurane group,355 789?28 116;1.5%Isoflurane group,238 554?31 531;(2.0%) Isoflurane group,223 632?25 710(P