Objective To develop an ultra high performance liquid chromatography-mass spectrometry(UPLC-MS)method for quantifying serum levels of norepinephrine(NE)and 5-hydroxytryptamine(5-HT),and to monitor the dynamic changes in these neurotransmitters during the process of establishing a model of acute reserpine-induced depression-like mice.Methods By evaluating matrix effect,recovery,precision,and accuracy efficiency,an UPLC-MS method for determining the concentrations of NE and 5-HT in serum was established.Forty-eight C57 mice were randomly divided into normal control and model groups,which were intraperitoneally injected with physiological saline(10 mL/kg)and reserpine(2.5 mg/kg),respectively.At various time points after intraperitoneal injection,the degree of ptosis and decreases in body temperature of the mice were observed before orbital blood was sample for the determination of NE and 5-HT levels.Results The concentrations of NE and 5-HT showed good linearity within the range of 15.63 to 2000.00 ng/mL,with R2 values greater than 0.999.The results of methodological validation met the requirements for the analysis of biological samples,with a lower limit of quantification of 15.63 ng/mg.After intraperitoneal injection of reserpine,the model mice exhibited varying body temperature decreases and ptosis.At 1 and 2 h post-administration,the depression-like symptoms in the model group were significantly different from those of the normal control group(P＜0.01).The body temperature of mice in the model group was significantly lower than that of mice in the normal control group(P＜0.01),while the score of the eyelid ptosis was significantly higher(P＜0.001).The levels of NE and 5-HT in the serum of model mice were also significantly depleted,and were significantly different from those of the normal control group at 0.5,1 and 2 h(P＜0.05).Conclusion The study process of established a rapid and accurate method for dynamically observing the changes in NE and 5-HT levels during the process of establishing a model of acute reserpine-induced depression-like mice,which might contribute to the study of the pathogenesis of depression and the development of new antidepressant drugs.

Objective To evaluate the use of endoscopic papillary balloon dilation in treatment of choledocholithiasis associated with peripapillary duodenal diverticulum.Methods From January 2017 to July 2018,a retrospective study was conducted on 124 patients with choledocholithiasis associated with peripapillary duodenal diverticula at the Department of Hepatobiliary Surgery,Second Hospital of Hebei Medical University.These patients were divided into the small endoscopic sphincterotomy combined with balloon dilation group (sEST+EPBD,n =60) and the simple papillary balloon dilation group (EPBD n =64).The operation time,one-time success rate of stone removal,complication and hospitalization stay were compared between the two groups of patients.Results The hospitalization expenses of the EPBD group was significantly less than the sEST+EPBD group (P＜0.05).The operation time of the EPBD group was significantly shorten than the sEST+EPBD group (P＜0.05).There were no significant differences in the one-time success rate of stone removal,complication rates and hospitalization stay between the two groups (P＞0.05).Conclusions Compared with sEST+EPBD,treatment of choledocholithiasis in patients with peripapillary duodenal diverticula using simple balloon dilation shortened the operation time,did not increase the complication rates and hospitalization stay.The procedure was safe and effective,and resulted in almost the same one-time success rate of stone removal.