Objective:To establish a measurement method for determining the levels of monoamines neurotransmitter and their metabolites in rat plasma by HPLC with Coularray Detector-2.Methods:The levels of NE

E

DA

HVA and 5-HT in rat plasma were determined by Agilent 1200 HPLC with ESA Coularray Detector-2.Mobile phase consisted of 80 mmol·L

-1

Citric acid monohydrate

73.4 mmol·L

-1

Citric acid trisodium salt

0.12 mmol·L

-1

1-Octanesulfonic acid sodium salt

0.1 mmol·L

-1

EDTA-Na

2

and 18% methanol mixture solution（pH4.3）.Flow rate was 1.0 mL·min

-1

.The Column was Zorbax Eclipse XDB-C

18

（4.6 mm×150 mm

5 μm）and Easyguard guard column at（25 ℃.） The voltage of electrode was-150 mv and 400 mv.Results:The minimum measurement limit of NE

E

DA

HVA and 5-HT were 2.0

3.0

5.4

5.2 and 11.1 ng·mL

-1

respectively.The average recoveries were 99.72%

85.33%

83.15%

120.43% and 103.56%

respectively.The RSD of intra-day（n=6） and inter-day（n=3） were less than 9.12%.Conclusion:The method was easy to operate

rapid

accuracy and high in sensitivity

and could be applied in quantitative determination and study of monoamines neurotransmitters and their metabolites in rat plasma.