Objective: To observe the change of amino acid transmitter and gamma-aminobutyric acid (GABA) receptor in the hypothalamus of burned rats during early stage, and to investigate its effect on the cardiovascular parameter of burned rats. Methods: 30%TBSA Ⅲ degree burn model of rat was made. Concentration of amino acid transmitter in the hypothalamus of burned rats was determined by auto-analysis of free amino acid. Radioligand binding assay was adopted to determine GABA receptor. The drug was injected into lateral ventricle (LV). Cardiovascular parameter was measured with four leads physiological recording instrument. Results: Concentration of GABA was significantly elevated, concentration of glutamate was reduced and there was no change of other amino acid transmitter in the hypothalamus of burned rats during early stage. Although maximum binding of GABA receptor increased significantly, there was no change of dissociation costant. Picrotoxin injection into LV may be significantly elevate MAP,LVSP,±dp/dtmax of burned rats. There were also limited effects of kinic acid (KA) on these parameters. Conclusion: The change of central GABA and glutamate transmitter may be a effecting factor on cardiovascular function failure of burned rats during early stage