Effects Of Ketamine Combined Anaesthetic On Amino Acid Neurotransmitter In Miniature Pigs

The study was based on ketamine combined anesthetic. In order to research the effects of ketaminecombined anesthetic and its main components on amino acid neurotransmitters in different encephalicregions of miniature pigs,65miniature pigs, were divided into5groups randomly, and injectedisochoric normal saline(10ml), diluent of ketamine (10.5mg/kg), midazolam (0.3mg/kg),xylidinothiazoline (2.5mg/kg) and combined anesthetic(0.08ml/kg). The different encephalic regionswere took at T1period(15min), T2period(45min) and T3period(75min), then the content of amino acidneurotransmitters were detected by high performance liquid chromatography (HPLC). According to thetendency of changes in different encephalic regions of amino acid neurotransmitters during theanesthesia process, investigating the possible active of the ketamine combined anesthetic and the maincomponents, and the possible channel of which involved in the anesthesia mechanism.Results:1. The contents of Asp and Glu in hippocampus, thalamus, cerebellum and brainstem at T1periodwere stepped down significantly by Ketamine. The contents of Gly in cerebrum, thalamus andbrainstem at T2period, the contents of GABA in cerebrum and thalamus at T2period were stepped upsignificantly by Ketamine.2. The contents of Asp in thalamus and cerebrum at T1period, brainstem at T2period, and thecontents of Glu in the five encephalic regions were stepped down significantly by Midazolam. Thecontents of Gly in cerebrum, hippocampus and cerebellum at T1period, thalamus at T2period, and thecontents of GABA in cerebrum, thalamus and brainstem at T1period were stepped up significantly byMidazolam.3. The contents of Asp in hippocampus, thalamus and brainstem at T1period, cerebellum at T2period, and the contents of Glu in the five encephalic regions were stepped down significantly byxylidinothiazoline. The contents of Gly in cerebrum and thalamus at T1period, the contents of GABAin cerebrum, thalamus and brainstem at T1period were stepped up significantly by xylidinothiazoline.4. The contents of Asp in hippocampus, cerebellum and brainstem at T1period, thalamus at T2period, and the contents of Glu in brainstem at T1period, cerebrum, hippocampus, thalamus andcerebellum at T2period were stepped down significantly by combined anesthetic. The contents of Glyin cerebrum, hippocampus and brainstem at T2period, and the contents of GABA in cerebrum,cerebellum and brainstem at T1period were stepped up significantly by combined anesthetic. Conclusion:Hippocampus, thalamus, cerebellum and brainstem are site of action caused the changes ofexcitatory neurotransmitters contents by ketamine; brainstem is site of action caused the changes ofexcitatory neurotransmitters by midazolam; cerebellum is site of action caused the changes of excitatoryneurotransmitters content by xylidinothiazoline; hippocampus, thalamus, cerebellum and brainstem arethe potential site of action caused the changes of excitatory neurotransmitters contents by combinedanesthetic. Ketamine played main place in hippocampus and thalamus of combined anesthetic group;there is synergistic effect of ketamine and xylidinothiazoline in cerebellum; and the same effect ofketamine and midazolam in brainstem.Cerebrum and thalamus are site of action caused the changes of inhibitory neurotransmittercontents by ketamine; cerebrum and cerebellum are site of action caused the changes of inhibitoryneurotransmitter contents by midazolam; cerebrum and thalamus are site of action caused the changesof inhibitory neurotransmitter contents by xylidinothiazoline; cerebrum is the potential site of actioncaused the changes of inhibitory neurotransmitter contents by combined anesthetic. There is synergisticeffect of ketamine, midazolam and xylidinothiazoline in cerebrum.