Hplc Combined With Microdialysis In The Anti-cerebral Ischemic Drug Screening Applications

Cerebral ischemia is a leading cause of death and serious, long-term disability in adults. The relation of neurotransmitters, espically neuronal amino acid and monoamine, and cerebral ischemia is always highlightened these years. In this paper, HPLC and microdialysis technique were combined to establish methods which can detect these neurotransmitters. Moreover, the methods were employed to study the effects and mechanisms of anti-ischemia medicine.Using HPLC and RF, methods detecting monoamine transmitters, such as NE, DA, 5-HT, and AA transmitters, such as Asp, Glu, Tau, GABA, in dialysate and brain homogenate were founded. The methods were convenient and effective.Using these methods, the change of neurotranismitters in the brain of cerebral ischemia mice induced by ligation of double lateral carotids was detected. The effects of Kedaling were also studied. In the study,the release of EAA and IAA in the brain of cerebral ischemia mice increased significantly. And the increase of IAA was higher. So Glu/GABA can reflect the grade of cerebral ischemia. After the mice were administrated with different concentration of Kedaling, the change of Glu/GABA was detected. Kedaling can inhibit the decrease of the ratio of Glu/GABA induced by cerebral ischemia. It is proved Kedaling can alleviate cerebral ischemia damage by regulateing the ratio of excitatory amino acid Glu and inhibitory amino acid GABA.By using microdialysis and HPLC, the method of monitoring the change of monoamine neurotransmitters in the striate of middle cerebral artery occlusion (MCAO) rats was established. The effects of Puerarin on monoamine in the MCAO rats were also studied. Results showed that after ischemia, the concertration of 5-HT increased. After 40 minutes of ischemia, the concertration of 5-HT reach the maximum level (p<0. 05) , which was 2. 78times basal levels. After 20 minutes of reperfusion, the concertration of 5~HT increased significantly(p<0. 05). Then it decreased. But it remained in a high degree. After the rats were given Puerain, the increase of the concertration of 5-HT Which compared with model was reduced. After 40 minutes of ischemia, the increase reduced(p<0. 05). After 20 minutes of reperfusion, 5-HT decreased significantly(p<0. 01). Then it increased. At last it retained to a normal degree. This proved Puerarin could alleviate cerebral ischemia damage.HPLC and microdialysis technique were combined to detect the unbalance of neurotransmitters in the brain of ischemia rats and the effects of medicine on these transmitters.This would be useful for the future studies in the effects and mechanism of anti-ischemia medicine.