The establishment of a sensitive method in determining different neurotransmitters simultaneously in rat brains by using liquid chromatography-electrospray tandem mass spectrometry

摘要

An effective way to determine the amount of different neurotransmitters is vital to the study of brain function. Here, a highly sensitive HPLC-MS/MS method was developed to simultaneously measure γ-aminobutyric acid, dopamine, epinephrine, norepinepherine, glutamate and serotonin in one sample. The quantification of the neurotransmitters was achieved by a tandem mass spectrometer using the selected reaction monitoring scan mode. The method validation included selectivity, linearity, accuracy, precision, stability, recovery and matrix effect. For the six neurotransmitters, the linear regression analysis was calibrated by deuterated internal standards with a R~2 of over 0.991, and the limit of detection (LOD) and the limit of quantification (LOQ) were from 2.5 to 500pg/mg and 7.5 to 1000pg/mg, respectively. This method was employed here to reveal different types and amounts of neurotransmitters simultaneously in adult and embryonic rat brains. Here, the change of dopamine concentration in embryonic and adult brain was from 0.071 to 0.760ng/mg of brain tissue, GABA was from 207.643 to 445.148ng/mg, glutamate was from 679.535 to 1408.920ng/mg, serotonin was from 0.058 to 0.485ng/mg and norepinepherine was from 0.054 to 0.290ng/mg. For epinephrine, it was only detected in embryonic stage but not in adult, with the concentration at 0.241ng/mg.