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Objective:(1) Models of depression (mice despair experimental model and mice learned helplessness experimental model) will be established to test the antidepressant effect of "N2011".(2) LC-MS is applied to determine the concentration of "N2011" in rat plasma for the purpose of pharmacokinetic.(3) In order to provide the basis for repeated administration, the concentration-time curve of "N2011" in rats will be studied.Methods:(1) Despair experimental model and learned helplessness experimental model will be established.Mice in the tests will be divided into negative control group (saline), experimental group ("N2011") and positive control group (ketamine). The anti-depressant effect of "N2011" will be evaluated according to the cumulative immobility time and the number of failed escape attempts.(2) LC-MS method will be developed for the determination of "N2011" concentration in rat plasma. Chromatographic conditions (type of chromatography column, proportion of the mobile phase, injection volume) and MS conditions (Fragmentor voltage, selection of optimal detection ion) will be optimized. It will be determined if there is interference of blank matrix to determination "N2011". The linearity, stability, precision, accuracy, extraction recovery and matrix effects of LC-MS method will be investigated.(3) Healthy SD rats (250-300g, half male and female) are used for test."N2011" concentration of all plasma samples are measured by LC-MS after administration at15time points (10,20,30,40,50,60,75,90,100,110,120, 150,180,240,360min),5rats in each time point.(4)"N2011" concentration time curve is drew, with sampling time as the axis (X), average drug concentration for the vertical axis (Y).The pharrnaeokinetic paramcters and compartment model are evaluated by special software DAS2.0. Results:(1) Mice forced swimming test (FST) results showed that the cumulative immobility time of the group of the positive control group (ketamine), low-dose group, middle dose group and high dose group showed significant difference respectively (P<0.05) comparing with the negative control group at each half an hour, two hours and four hours after administration, and there is no significant difference among the three doses (P>0.05). Comparing with the negative control group at six half after administration, the cumulative immobility time of positive control group were respectively shorten evidently (P<0.05), but the cumulative immobility time of low-dose group, middle dose group and high dose group had no significant difference (P>0.05) respectively.(2) Mice helplessness experimental model results showed that the number of mice failed escape of the positive control group (ketamine), low-dose group, and high dose group were respectively decreased evidently (P<0.05) comparing with the negative control group at each half an hour, two hours and four hours after administration, and there is no significant difference between the two doses (P>0.05).(3) HPLC conditions:C18column (Agilent,5m,4.6×15mm), pre-column (Agilent,4mm×2.0), the column temperature was30℃, methanol-ammonium acetate solution (pH7.20) mobile phase(flow rate: 0.6mL/min), injection volume:10μL, detection wavelength:274nm. MS conditions:the electrospray ionization source was performed on single rod quadrupole tandem mass spectrometry using the technique in positive ionization mode. Plasma endogenous impurities did not interfere with the determination of "N2011" in rats plasma samples. There was no obvious ion suppression or enhancement phenomen causing of matrix when "N2011" was assayed. The method established showed a good linear relationship from5.00to120.00ng/mL,(r2=0.9957, n=6).(4) The pharrnaeokinetic parameters and compartment model were dealed by DAS special software. The drugs-time curve of "N2011" in rats vivo metabolism was obtained. Pharmacokinetic models in rats vivo is the single-chamber model. The main Phannaeokineties parameters showed that peak concentration is113.79ng/mL and the half-life is2.42h.Conclusion:(1)The results showed the rapid antidepressant effect of "N2011" which is last at4hours, and the effect is not positive correlate with dosage.(2) The established method (LC-MS) is accurate and efficient for assaying the "N2011" in rat plasma.(3)The peak concentration of "N2011" in rats is113.79ng/mL, and the half-life of "N2011" is2.42h.
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