The Changes Of Endogenous Opioid Peptides In Patients With General Anesthesia And The Influence Factor Explored

Objective:1.The aim of this study was to investigate the changes of endogenous opioid peptides in leukocytes and plasma during scheduled surgery performed under intravenous general anesthesia.2.To explore the effect of noradrenaline on leukocyte-derived b-endorphin.Methods:1.Forty-eight cases of patients(age ranging from 24 to 70 years old and ASA gradeⅠ-Ⅱ)were anesthesia and blood was collected before and after anesthesia.The peripheral white blood cell(WBC)counts and classification were assessed.Flow cytometry was used to test the expression of b-endorphin(b-EP)in leukocytes.The plasma concentration of b-EP and leuthine enkephalin(LEK)were measured using radioimmunoassay(RIA).2.The effect of noradrenaline(10-5 mol/L)on leukocyte-derived b-endorphin was observed pre-adminstration,immediately and 30 min,1 hr,2 hrs after administration noradrenaline.Results:1.The WBC after operation were significantly higher than that before operation(P<0.01).According to the differential WBC counts,granulocytes(G)and monocytes(Mon)were higher after operation,whereas the lymphocytes(Lym)were lower(P<0.01).The percentage of G was significantly higher but the percentage of Lym was lower,while there was no significant difference in the Mon.The Neutrophil-lymphocyte ratio(NLR)was significantly higher than that before operation(P<0.01).The mean fluorescence intensity(MFI)of b-EP in leukocytes after operation was significantly lower than that before operation(P<0.05).The percentage of granulocytes containing b-EP fluorescence positive cells was significantly reduced(P<0.05),and lymphocytes and monocytes showed a trend of decline.The plasma concentration of b-EP and LEK were also significantly reduced at the end of anesthesia(P<0.01).2.In vitro,the MFI of b-endorphin in granulocytes(G),monocytes(Mon)and lymphocytes(Lym)had a tendency to increase at 30 min after adminstration noradrenaline(10-5 mol/L),then at 1 hr and 2 hrs,the MFI of b-endorphin gradually decreased.There was no significant difference between the time points(P>0.05).Conclusion:1.The WBC after operation were significantly higher than that before operation,mainly G.The content of endogenous opioid peptides in leukocytes and plasma are reduced.2.The noradrenaline can make the expression of leukocyte-derived b-endorphin increased in a short time.