The use-dependent characteristics of daurisoline on monophasic action potentials (MAP) of the left ventricle of the rabbit heart in situ were recorded with MAP recording technique. The results showed that daurisoline decreased monophasic action potential amplitude (MAPA) and prolonged monophasic action potential duration at the 50% and 90% (MAPD50, MAPD90), effective refractory period (ERP), ERP/MAPD90 at the steady-state cycle lengths of 240, 210, 180 ms. The percent of prolongation of MAPD50 was 12.8±2.9, 9.5±2.6, 9.0±1.6, that of MAPD90 was 10.9±2.6, 7.5±2.4, 6.5±2.7, that of ERP was 25.7±4.3, 18.5±4.1, 24.2±7.2, and that of ERP/MAPD90 was 13.7±4.5, 10.2±2.2, 16.1±5.1, respectively. Its effect showed no relation to frequency (n=6, P>0.05). The effects of sotalol on MAP were similar to that of daurisoline, but it prolonged MAPD90 and ERP in a reverse use-dependent manner (P<0.05). It is concluded that daurisoline has no use-dependent effects on MAP of rabbit hearts.

Objective To explore the expressions and changes of endogenous neural stem cells (ENSCs) and Notch-1 after acute spinal cord injury in adult rats,and to explore its role in the nerve regeneration process.Methods The 30 Sprague Dawley (SD) female rats (3-6 months) (300-350 g) were divided into control groups (n =5) and experimental group (n =25) by digital random method.The control group only accepted lamina decompression,and the experimental group was the spinal cord injury group.Five rats were drawn when at 1 d,3 d,1 w,2 w,and 4 w,then behavior,histology,immunohistochemistry and immunofluorescence method were used to detect the proliferation and expression of endogenous neural stem cells and Notch-1 protein.Results Behavioral observation showed the experimental group rats were disfunction.Histological observation showed nerve fiber structure turbulence,edema and denaturation in the experimental group.Immunohistochemistry staining showed the Notch-1 expression every experimental group.Notch-1 positive cell peaked at 3 days.Immunofluorescence test showed,in the experimental group damage to segment the area surrounding the BrdU positive staining cells was significantly higher than the control group.Using three-dimensional quantitative study method detected in 1 w after spinal cord injury was the number of newborn cells mitosis,most about was about 75 times in the control group.Linear regression method was used to analyze the different time points after BrdU and Notch-1 protein expression positive area,the area of the results found that both into linear correlation.Conclusions The new born neurons after spinal cord injury in rats Notch-1 expression has a certain relevance.In addition,the expression of signal protein Notch-1,might be associated with early proliferation of ENSCs in rats.

ABSTRACT OBJECTIVE：To establish a method for the determination of 5-hydroxyindole acetic acid（5-HIAA），glutamine， hippurate，pimelate，proline，tryptophan，tyramine，tyrosine and valine in human urine. METHODS：Morning urine samples were collected from depression patients. The sample was extracted with acetonitrile after addition of internal standard cortisone. LC-MS/ MS method was adopted. The determination was performed on XTerra RP18 column with mobile phase consisted of 0.1％ acetic acid-water as mobile phase A and 0.1％ acetic acid-acetonitrile as mobile phase B（gradient elution）. The column temperature was set at 40 ℃，and flow rate was 0.45 mL/min. Electrospray ion source（ESI）was used for quantitative analysis by multiple reaction monitoring （MRM）. The precursor/product ion transitions （m/z） were monitored at m/z 192.2→146.1，m/z 147.2→130.0，m/z 180.1→105.1，m/z 161.1→125.2，m/z 116.1→70.2，m/z 205.2→188.2，m/z 138.2→121.1，m/z 182.0→123.0，m/z 118.2→72.1 and m/z 361.2→163.0（+ion-mode）for 5-HIAA，glutamine，hippurate，pimelate，proline，tryptophan，tyramine，tyrosine，valine and cortisone，respectively. RESULTS：The linear range of 5-HIAA，glutamine，pimelate，proline，tyramine and valine were 10.00-3 200 ng/mL（r＝0.993 8-0.998 9，n＝6）. The lower limit of quantification was 10 ng/mL；the linear range of hippurate，tryptophan and tyrosine were 1 600-51 200 ng/mL（r＝0.999 2-0.999 7，n＝6）. The lower limit of quantitation was 1 600 ng/mL. The results of accuracy tests were 86.29％-98.65％（n＝6）. RSDs of intra-day and inter-day precision tests were no more than 14.65％（n＝6）CV of matrix effect were 6.18％-14.37％（n＝6）. Extraction recovery rates were 86.21％-98.14％（n＝6）. RE of stability tests were no more than 14.71％（n＝3-6）. CONCLUSIONS：The method is sensitive，accurate and suitable for the determination of 9 substances in human.