Objective: To observe the effects of Tianma Gouteng Fang (TGF) on the transmitter amino acids in the hippocampus extracellular liquids in freely moving rats subjected to incomplete brain ischemia.
Method: Hippocampus extracellular liquids was collected continuously by the microdialysis sampling technology in freely moving rats during pre-ischemia, incomplete ischemia and reperfusion periods induced by the occlusion and loose of both common carotid arteries. Each dialysate sample was assayed for GABA, Tau, Glu, Cys and Arg with HPLC-electrochemical detector.
Result: TGF increased the concentrations of GABA and Tau in the extracellular liquids of rat hippocampus. Compared with the model group, the concentration of Glu in the middle and large dosage groups of TGF, during the 120 min of ischemia, reduced by 38.64% and 31.35%, Tau increased by 13.99% and 12.86%, GABA advanced 25.89% and 33.99%, Cys decreased by 40.93% and 42.08%, Arg raised to 116.95% and 108.96%, respectively. After 120 min of reperfusion, the concentration of Glu decreased by 14.55% and 11.48%, Tau increased by 16.13% and 14.03%, GABA increased by 24.41% and 26.22%, respectively.
Conclusion: TGF can increase the concentration of inhibitory amino acids in hippocampus extracellular liquids of rats and inhibit the excessive release of excitatory amino acids and raise the concentration of the inhibitory amino acids and Arg during the ischemia-reperfusion periods. Therefore, TGF can play the neuroprotective role.