Davis D W, Mans A M, Biebuyck J F, Hawkins R A
Anesthesiology. 1986 Jun;64(6):751-7. doi: 10.1097/00000542-198606000-00013.
The influence of etomidate on regional cerebral function as reflected by regional cerebral glucose utilization (rCMRGlc) was studied. Three experiments were performed. In the first, rats had both left femoral vessels cannulated and were placed in restraining cages. Etomidate was infused intravenously (12 mg/kg) at a rate of 6 mg X kg-1 X min-1. This large dose had a modest effect on blood pressure and heart rate, which could be explained by the elimination of stress in restrained rats, and no effect on body temperature, Pao2, PaCo2, or pH. A second group of rats were used to determine the effect of etomidate on the ratio of brain glucose to plasma glucose, which is necessary for calculating rCMRGlc. In the third experiment rCMRGlc was measured in unstressed rats. The rats were anesthetized with an intravenous dose of 1, 2, 6, or 12 mg/kg etomidate infused at a rate of 6 mg X kg-1 X min-1. Etomidate had a marked effect on glucose consumption in many, but not all, cerebral structures. The forebrain (telencephalon and diencephalon) was most affected (-25% to -35%) while the hindbrain was minimally affected. There was no demonstrable dose dependency; 1 mg/kg depressed rCMRGlc as much as 12 mg/kg. The pattern of rCMRGlc depression is in accord with the minimal effects observed on physiologic variables and similar to that caused by the steroid anesthetic Althesin, although the depression seen was not as severe. The pattern of metabolic depression produced by etomidate differs markedly from that produced by barbiturates, which affect all brain regions to a similar degree.(ABSTRACT TRUNCATED AT 250 WORDS)
研究了依托咪酯对局部脑葡萄糖利用（rCMRGlc）所反映的局部脑功能的影响。进行了三项实验。第一项实验中，给大鼠双侧股动静脉插管并置于束缚笼中。依托咪酯以6mg·kg⁻¹·min⁻¹的速率静脉输注（12mg/kg）。如此大的剂量对血压和心率有适度影响，这可归因于消除了束缚大鼠的应激反应，且对体温、动脉血氧分压（Pao2）、动脉血二氧化碳分压（PaCo2）或pH值无影响。第二组大鼠用于确定依托咪酯对脑葡萄糖与血浆葡萄糖比值的影响，这是计算rCMRGlc所必需的。在第三项实验中，测量了未受应激大鼠的rCMRGlc。大鼠静脉注射1、2、6或12mg/kg依托咪酯，输注速率为6mg·kg⁻¹·min⁻¹进行麻醉。依托咪酯对许多但并非所有脑结构的葡萄糖消耗有显著影响。前脑（端脑和间脑）受影响最大（降低25%至35%），而后脑受影响最小。未显示出明显的剂量依赖性；1mg/kg与12mg/kg降低rCMRGlc的程度相同。rCMRGlc降低的模式与对生理变量观察到的最小影响一致，且与类固醇麻醉药阿法沙龙引起的模式相似，尽管观察到的降低程度没那么严重。依托咪酯产生的代谢抑制模式与巴比妥类药物产生的模式明显不同，巴比妥类药物对所有脑区的影响程度相似。（摘要截于250字）
