The Study Of AQP-1and AQP-5Expression In The Animal Model Of ALL Induced By LPS And CGRP Intervention

ObjectiveIn juvenile rats as experimental object,to establish the animal model ofALI induced by the lipopolysaccharide (LPS),to observe the expressionof AQP-1, and AQP-5;to discuss the relationship of the pulmonaryedema and lung AQPs in the physiological and pathological conditions ofacute; Clarify CGRP were the regulation function in the expression ofAQP-1, and AQP-5.MethodChooseing the SD rats about144,they are1month and the weight is70-100g, according to random number table method they are divided into thecontrol group (by intraperitoneal injection amount of saline);, the LPSgroup (celiac injection of LPS5mg/Kg), CGRP intervention group (10minafter LPS injection by intraperitoneal injection of CGRP1.0mg/Kg),each group of48, in each time point there are8in each group. Afterthe injection of LPS0,2,6,12,24and48h they will be put to death.In each time point of the injection of LPS we will evaluat the secretionlevel of CGRP of lung tissue by ELISA method; in different groups ineach time point we will observe the severity level of the lung injury bytheLight microscopy By rt-pcr and Western blot method when CGRPinterved to observe the level of theexpressionof AOP1and AQP5.Results In the lung tissue homogenate of rats after processing by the LPS, Therelease of CGRP are increasing, at6h, increasing significantly (p <0.01), after12h, rapidly falling; after the intervention by the CGRP,CGRP releasing to the LPS group will decrease obviously, but comparedwith control group, it still increases slowly over time. About6h and12h it will be at their peak levels, after24h it will decrease. Afterinjection of the LPS the expression level about AQP-1, and AQP-5inmore than four time points will reduce quickly, and will be lower thanthe control group. Then there is significant difference (p <0.05) andpulmonary edema was observed under the light at the same time; after theintervention of the CGRP, the expression level of the AQP1and AQP-5at all time points were significantly increased, and the correspondingtime point will be higher than the LPS group, but it will be still lowerthan the control group. The differences were statistically significant(p <0.05) and pulmonary edema was observed under the light at the sametime.ConclusionThis experiment selects the rats as experimental object and to establishthe animal model of ALI induced by the lipopolysaccharide (LPS),byinspecting of related parameters of lung injury and pathologicalhistology observation it prove the animal model of ALI induced bythelipopolysaccharide (LPS) is successful, to watch the changes aboutthe AQP1,5and AQP-l,5mRNA level of protein expression and theeffect of intervention,to clarify CGRP were the regulation function inthe expression of AQP-1, and AQP-5. Results indicate as follows:1.CGRP can relieve the pathology change of the acute lung injury inrats, that CGRP have better protective effect on acute lung injury.2.AQP expression in acute lung injury group is a significant reduction, so we concluded that the significant reduction of AQP1and5lead theabsorption ability about pulmonary edema fluid acrossing the cellmembrane absorption to drop, this may be one of the important factors toacute lung injury.3.After CGRP intervention, the protein expression increasedsignificantly, it suggest CGRP can raise the protein expression in theanimal model of ALI induced by the LPS, and it is the one of themechanisms on ALI protection.