脑摄取动态平衡时不同麻醉深度丙泊酚对犬脑不同区域γ-氨基丁酸的影响  

Effect of propofol at uptake equilibrium on γ-aminobutyric acid in different cerebral regions in dogs

作　　者：汪燕[1] 林春水[1] 古妙宁[1] 郭高锋[1] 周枝凤[2] 陈莺[1] 

机构地区：[1]南方医科大学南方医院麻醉科,广东广州510515 [2]南方医科大学公共卫生与热带医学学院,广东广州510515

出　　处：《南方医科大学学报》2012年第3期427-429,431,共4页Journal of Southern Medical University

基　　金：广东省自然科学基金(9151051501000054)

摘　　要：目的观察脑摄取动态平衡时不同麻醉深度丙泊酚对犬脑不同区域γ-氨基丁酸(GABA)的影响。方法 12只12-18月健康杂种犬,随机分为浅麻醉组和深麻醉组,每组6只。浅麻醉组:静脉注入丙泊酚5.5 mg/kg(时间15 s),续以55 mg/kg/h恒速静脉输注。深麻醉组:静脉注入丙泊酚7.0 mg/kg(时间15 s),续以70 mg/kg/h恒速静脉输注。2组丙泊酚恒速输注50 min时取颈内动、静脉血各2 ml,同时断头处死,解剖犬脑取背侧丘脑、上丘脑、后丘脑、下丘脑、底丘脑、额叶、顶叶、颞叶、枕叶、海马、扣带回、小脑、中脑、脑桥、延髓、颈髓组织,采用高效液相色谱法(HPLC)检测颈内动、静脉血浆丙泊酚浓度和各区域脑组织GABA含量。结果浅麻醉组:颈内动、静脉血浆丙泊酚浓度分别为3.00±0.31和3.10±0.51μg/ml,差异无统计学意义(P>0.05);深麻醉组:颈内动、静脉血浆丙泊酚浓度分别为6.41±0.05和6.40±0.11μg/ml,差异无统计学意义(P>0.05)。深麻醉组各脑区GABA浓度均明显高于浅麻醉组(P<0.05);在两种麻醉深度下背侧丘脑和下丘脑GABA变化率分别为(83.83±2.23)%,(85.83±1.72)%,明显高于其它脑区(P<0.05)。结论丙泊酚恒速静脉输注50 min时,两组犬脑颈内动、静脉血药浓度均达到平衡;深麻醉组各脑区GABA浓度均明显高于浅麻醉组,背侧丘脑和下丘脑GABA变化率高于其他脑组织,提示丙泊酚麻醉深度与GABA含量相关,背侧丘脑和下丘脑GABA的变化在丙泊酚麻醉中发挥重要的作用。Objective To investigate the effect of propofol at doses for different anesthesia depths on γ-aminobutyric acid（GABA） in different cerebral regions at propofol uptake equilibrium in dogs.Methods Twelve 12-18-month-old healthy hybrid dogs weighing 10-12 kg were randomly divided into light anesthesia group（n=6） and deep anesthesia group（n=6） with a single bolus dose of propofol（5.5 and 7.0 mg/kg,respectively） completed in 15 s followed by intravenous propofol infusion at a constant rate（55 and 70 mg·kg-1·h-1,respectively）.Blood samples（2 ml） were taken from the internal carotid artery and jugular vein to measure plasma propofol concentrations 50 min after the start of the infusion.The dogs were then sacrificed and tissues were taken from different brain regions and the cervical cord to measure GABA concentrations using high-pressure liquid chromatography（HPLC）.Results The plasma propofol concentrations in internal carotid artery and jugular vein were similar in both light anesthesia group（3.00±0.31 and 3.10±0.51 μg/ml,respectively,P0.05） and deep anesthesia group（6.41±0.05 and 6.40±0.11 μg/ml,respectively,P0.05）.GABA concentrations in the brain regions were significantly higher in deep anesthesia group than in light anesthesia group（P0.05）.The dorsal thalamus and hypothalamus showed greater GABA variations [（83.83±2.230%） and（85.83±1.72）%] compared to other brain regions at different anesthesia depths（P0.05）.Conclusions In both groups,plasma propofol concentrations in the internal carotid artery and internal jugular vein reach equilibrium at 50 min of propofol infusion.The variation of GABA is associated with the anesthesia depth of propofol,and GABA variation in the dorsal thalamus and hypothalamus plays an important role in propofol anesthesia.

关 键 词：丙泊酚 Γ-氨基丁酸 犬 脑 血浆浓度 

分 类 号：R614[医药卫生—麻醉学]