Brain Slice Glucose Utilization
Brain Slice Glucose Utilization
复制标题
脑切片葡萄糖利用
作者：
G. Newman;F. Hospod;C. Patlak
摘要：研究了540 μm和1000 μm下丘脑脑组织2 -脱氧葡萄糖的代谢。切片2 -脱氧葡萄糖（2DG）和2 -脱氧葡萄糖- 6 -磷酸（2DG6P）水平在组织匀浆和高氯酸萃取后测定。通过用非线性最小二乘法分析摄取和冲洗动力学，我们确定了三参数、四参数或五参数动力学模型的速率常数，并获得了体外集中常数（LC）的值。动力学分析揭示了一个小的，缓慢衰减的2DG成分，这是任何模型都无法预测的。如果这个组件被视为一个独立的，平行的隔间，那么四参数和五参数模型本质上是等效的。为了将我们的数据与之前的体内数据进行比较，我们将2DG和2DG6P结合产生总切片放射性Ci*，并分析了摄取的前45分钟。这些数据最适合于三参数模型，缓慢衰减池没有被识别出来。通过全切片均匀化和au - torx射线图像分析，计算组织总放射性的葡萄糖利用率，显示出两种方法之间的良好相关性。图像分析显示，在这些切片中存在的视交叉上核放射性，揭示了体外葡萄糖利用的自发日变化，与先前的体内测量结果密切一致。1000 μm切片的动力学分析与540 μm切片的定性相似，但LC增加，k1大幅降低，己糖激酶速率常数k3如预期的那样大幅增加。总体而言，体外葡萄糖利用率提高了约60%。这些结果与我们之前对1000 μm切片的研究一致，并支持我们的解释，即1000 μm切片是一个很好的脑缺血无梗死的体外模型。
Abstract: The metabolism of 2‐deoxyglucose has been studied in 540 μm and 1,000 μm hypothalamic brain slices. Slice 2‐deoxyglucose (2DG) and 2‐deoxyglucose‐6‐phosphate (2DG6P) levels were measured after tissue homogenization and perchloric acid extraction. By analyzing the uptake and washout kinetics with nonlinear least‐squares methods, we have determined the rate constants for three‐, four‐, or five‐parameter kinetic models and obtained a value for the in vitro lumped constant (LC). The kinetic analysis reveals a small, slowly decaying, 2DG component that is not predicted by any of the models. If this component is treated as a separate, parallel compartment, then the four‐ and five‐parameter models are essentially equivalent. To compare our data to prior in vivo data, we combined 2DG and 2DG6P to produce Ci*, the total slice radioactivity, and analyzed the first 45 min of uptake. These data were fit best by a three‐parameter model and the slowly decaying pool was not identified. Calculation of glucose utilization from total tissue radioactivity, measured by whole slice homogenization and by image analysis of au‐toradiograms, showed excellent correlation between the two methods. Image analysis of radioactivity in the suprachias‐matic nucleus, which is present in these slices, revealed a spontaneous diurnal variation in in vitro glucose utilization in close quantitative agreement with prior in vivo measurements. The kinetic analysis of the 1,000 μm slice was qualitatively similar to that of the 540 μm slice but revealed an increase in the LC and a large decrease in k1 as well as the expected large increase in the hexokinase rate constant, k3. Overall, in vitro glucose utilization increased by about 60%. These results are consistent with our prior studies of the 1,000 μm slice and support our interpretation that the 1,000 μm slice is an excellent in vitro model for brain ischemia without infarction.
分级缺氧对海马切片的影响：缺血半暗带的体外模型。
影响因子：
8.3
作者：
Schiff,SJ;Somjen,GG
通讯作者：
Somjen,GG
影响因子：
56.9
作者：
PHELPS, ME;MAZZIOTTA, JC
通讯作者：
MAZZIOTTA, JC
缺血时的脑代谢：治疗的神经化学基础。
影响因子：
9.8
作者：
Siesjö,BK;Wieloch,T
通讯作者：
Wieloch,T