Studies On The Effects Of Polydatin On The Imbalance Of Th1/Th2 With Endotoxic Shock-Induced Lung Injury In Rats

PART ONEACUTE LUNG INJURY INDUCED BY ENDOTOXIC SHOCK AND IMBALANCE OF TH1/TH2 TYPE OF CYTOKINESAcute lung injury(ALI) induced by the endotoxic shock appears early and frequently after severe infection and wound. The inflammatory response is out of control may contribute to it and may be reflected by the imbalance of Th1/Th2 type of cytokines. Whether Th1 or Th2 type cytokines play a predominant role in it has been a controversial issue. In this study, ALI rats model was made by injecting lipopolysaccharide(LPS) into jugular. Enzyme-linked immunosorbed assay(ELISA) is employed tomeasure interferon-γ(IFN-γ) level,interleukine-4(IL-4) level and the ratio of IFN-γ/IL-4, pathological examination is made under optical microscope at the same time to investigate the type of imbalance cytokines and its relation to the ALI induced by endotoxic shock.Our findings indicate that:1.Compared with normal control group, the IFN-γ level ,the ratio of IFN-γ/IL-4 were significantly increased whereas IL-4 level didn't change obviously.2.Pathological examination of lung tissue proved the ALI occurred in rats.Our studies suggest that:1.The imbalance of Th1/Th2 type cytokines exists in the endotoxic shock-induced ALI. The polarization of T helper cells is related to the genetic background of the host, the circumstances and the stage of the disease.2.Once the imbalance of Th1/Th2 type cytokines appears, the abnormal cytokines would cause tissue injury directly or indirectly.3.Increasing of Th1 type cytokines may result from LPS activating dendritic cells (DCs) to secrete interferon γ-promoting factors such as IL-12,IL-18 and IL-23,as well as imbalance of interactions with natural susceptible system of endotoxin and detoxification.KEY WORDS: endotoxic shock;acute lung injury;Th1/Th2;cytokine...