Function Of Gq/11 Protein In The Small Intestine Injury During Acute Respiratory Distress Syndrome And Propofol Pre-treatment

Objective:The alteration of expression Gq/11 protein in the small intestine were studied during acute respiratory distress syndrone (ARDS) and propofol pre-treatment to explore the mechanism of ARDS and provide reference for the disease therapy. Methods: To establish an ARDS model in rats by intravenous oleic acid(OA).48 male and healthy wistar rats were randomly divided into control group(C group,n=8) given normal saline,at 0.2ml.Kg~-1, pre-treatment group(P group,n=8) received propofol at 80mg.Kg~-1.h~-1 through left internal jugular vein for half hour before given OA (0.2ml.Kg~-1),and oleic acid(OA, n=32)groups.According to time limit, OA groups were divided into 4 groups OA30min, 60min, 90min, 120min after injected OA at 0.2ml.Kg~-1 through tail vein.Blood gas, plasma and the small intestine homogenate ACE, LDH activity and MDA content were assessed during the experimental period and the concentration of Gq/11 protein were measured by Western blot.Results: Compared with C group, PaO2 of OA groups and P group obviously decreased (P<0.01), but PaO2 of P group was higher than that of OA groups (P<0.01). pH of OA30min group was higher than that of C group (P<0.05), furthermore OA 90min and OA120min groups were markedly reduced(P<0.01). pH also reduced in P group, compared with C group (P<0.01), but was higher than that in OA 90min and OA120min groups (P<0.01). Compared with C group, ACE activity of OA groups except OA 30min in plasma were lower than those of C group and indecreasingtendency with time passing. LDA level and MDA content in plasma of OA 60minN 90min> 120min significantly increased (P<0.01).To contrast with C group,ACE activity and MDA content in tissue of OA 90min and 120min were notably higher than those of C group (P<0.01); The level of LDA increased frome 60min(P<0.01 or P<0.05).In comparsion with C group,the concentration of Gq/11 protein of OA 60, 90 ^ 120min respectively increased, and it was in ascending tendency with time passing.the concentration of P group was higher than OA30min and lower than OA120min. In plasma, the activity of ACE of P group was more higher than C group(P<0.05).But lower significantly than OA 120min.There were no difference of index of LDH in plasm between P group and C group.But P group was lower than OA groups on index (P<0.01).MDA content of P group was a little higher than C group but lower than OA 90 n 120min in plasma.In intestine,LDA and ACE of P group were higher than C group and lower than OA 120min,and MDA of P group has no difference with C group but was notably lower than OA90> 120min.MAP of P group was the lowest among all of groups. Conclusions: l)Up regulation of the expression of Gq/11 may play a role in ARDS small intestivne injury. 2)Pre-treatment with propofol can decrease the expression of Gq/11 in the small intestine tissue and relieve the injury of the small intestine during ARDS.