OBJECTIVE:To establish a method for simultaneous determination of sodium valproate(VPA)and its metabo-lite 2-propyl-2-pentenoic acid (2-ene-VPA) in human plasma. METHODS:Plasma sample was extracted with cyclohexane and experienced derivatization with 2,4′-dibromoacetophenone using n-octanoic acid as an internal standard. RP-HPLC method was adopted. The determination was performed on Zorbax SB-C18 column with mobile phase consisted of acetonitrile-water(65∶35,V/V)at the flow rate of 1 mL/min. The column temperature was set at 35 ℃,and UV dectection wavelenth was set at 258 nm. The sample size was 20 μL. RESULTS:The linear range of VPA and 2-ene-VPA were 5.0-200.0,0.5-20.0 μg/mL(r=0.999 9, n=5). The limits of quantification were 5.0,0.5 μg/mL. RSDs of inter-day and intra-day were all lower than 5%. Method recov-eries were 95.99%-98.80%and 97.40%-98.17%,and extraction recoveries were 80.46%-86.23%and 80.45%-85.61%. The plas-ma concentrations of VPA in 10 epileptic children were 27.4-93.2 μg/mL,and those of 2-ene-VPA were 0.85-3.94 μg/mL,respec-tively. CONCLUSIONS:The method is simple,specific and suitable for plasma concentration determination and pharmacokinet-ic study of VPA.

Objective:To investigate the attentional bias for negative emotional facial expressions in major depressive disorder(MDD).Methods:Twenty MDD participants were selected from a larger pool of patients (n=35),diagnosed as depression with the Chinese Classification and Diagnostic Criteria of Mental Disorders Version 3 (CCMD-3),according to the Hamilton Depression Scale (HAMD) and Beck Depression Inventory (BDI).And 20 non-depression control participants(NC)matched with MDD group on age,gender and education level.All participants completed an exogenous cueing task which consisted of two kinds of cue types(valid and invalid trial)and two kinds of face types(neutral faces and negative faces).Results:Patients with MDD showed more larger cue validity effect for negative faces compared with neutral faces(21.73 ms vs.3.91 ms,P<0.01).They showed a stronger attentional engagement for negative faces in comparison with non-depressed participants(17.25 ms vs.1.64 ms,P<0.001).The NC group directed attention away from negative faces,more rapidly disengaging their attention compared with MDD,but the differences showed no significant(-1.50 ms vs.0.57 ms,P>0.05).Conclusion:These results support the assumption that MDD is associated with attentional bias for negative information,and deficits protective bias for it.