Effects Of The Penehychdine Hydrochloride On The CD14 And TLR4 Gene Expression In Endotoxin Induced Acute Lung Injury In Neonatal Rats

Acute lung injury(ALI) is an acute progressive respiratory failure induced by various reaseons except cardiogenic factors with high mortality. Lipopolysaccharide(LPS), a mojor component of Gram-negative bacterial endotoxin, is the leading cause of ALI. So far, there are still no effective antiendotoxin drugs.ObjectivePenehyclidine Hydrochoride injection is the new development anti-choline medicine, can improve the cells'toleration on ischemia and hypoxia, stabilize subcellular structure of cytolysosome and chondriosome,reduse the releasing of lysosomal enzyme,inhibite the information of metabolite of arachidonic acid and shock factors,release the systemic inflammatorome responded. However, the precise mechanism are not as yet fully understood. Our goal is to investigate the protective mechanism of penehychdine hydrochloride against acute lung injury induced by endotoxin in neonatal rats.MethodsForty 7 days old Wistar rats were randomly divided into 4 groups(n=10 each): group NS, which was treated identically to the group LPS except for the substitution of 0.9% saline for LPS; group LPS,which was given LPS injection intraperitoneally (5mg/kg) to reproduce the ALI rats models; group PL, which received intraperitoneal injection of penehychdine hydrochloride (0.1mg/kg) while they were induced by intraperitoneal infection of LPS; group PH,which received intraperitoneal injection of penehychdine hydrochloride (0.5 mg/kg) just after the infection of LPS. After 4 hours, they were killed. Then the lungs were removed.Levels of CD14 and TLR4 mRNA in lung were determined with RT-PCR.The expression of TNF-α, IL-1β, IL-10 in the lung tissues were detected by enzyme linked immune adsorbing analysis (ELISA). Furthermore, the lung pathologic structure were observed under the optical microscope and transmission electron microscope. By microscopy,each group had classic change presenting acute lung injury which included, the infiltration of inflammatory cells, alveolar septum widen,the leakage of erythrocyte except group A,which had normal lung construction. Group LPS had most severe pathologic changes.In the group PH, the according pathological changes were slighter than group PL.Under the transmission electron microscope, in the group LPS, the microvilli on the surface of ATⅡcells disappeared;lamellar bodyincreased enlarged in size and reduced in density; The number of mitochondria increased, and some of them became swollen and enlarged. The pathological changes were attenuated in group PL and PH with the latter being even more improved.There was significant difference on expression of CD14 and TRL4 in lung of neonatal rats among four groups.Compared with NS group,the expression of CD14 and TRL4 of lung tissues in the group LPS increased obviously(P<0.05). Compared with LPS group, the level of CD14 and TRL4 of lung tissues in the group PL and PH decreased (P<0.05). Furthermore, group PH was lower than that of group PL.Content of TNF-α, IL-1βand IL-10 protein were significantly higher in group L, PL and PH than in group C (P<0.05) and were significantly lower in group PH1 and PH2 than in group L (P<0.05).ConclusionsPenehychdine hydrochloride has the protective effect on ALI.The mechanisms of the effect are due to its ability of inhibiting the expression of CD14 and TRL4, thereby inhibit the development of uncontrolled inflammation at the development of ALI.