THEORY OF THE USE OF ARTERIOVENOUS CONCENTRATION DIFFERENCES FOR MEASURING METABOLISM IN STEADY AND NON-STEADY STATES.
THEORY OF THE USE OF ARTERIOVENOUS CONCENTRATION DIFFERENCES FOR MEASURING METABOLISM IN STEADY AND NON-STEADY STATES.
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使用动静脉浓度差异测量稳态和非稳态代谢的理论。
DOI：
10.1172/jci104437
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发表时间：
1961
期刊：
影响因子：
--
通讯作者：
K. Zierler
中科院分区：
文献类型：
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作者：
K. Zierler
越来越多的研究人员正在测量动脉血和静脉血中某些物质的浓度，并将从同时采集的动脉和静脉样本中获得的动静脉 (AV) 浓度差异与静脉系统取样的组织吸收或释放代谢物的浓度差异等同起来。 AV 浓度差异作为组织代谢的有效估计值的条件受到极大限制，尽管文献中确实包含充分的警告（例如参考文献 1-3），但这些限制似乎经常被误解，以至于人们认为重新检查该问题可能会有所帮助。从根本上讲，所有此类研究都希望采用菲克原理（4），该原理指出，如果：a）物质x的动脉浓度恒定，b）如果x的静脉浓度恒定，C）如果血流量v恒定，d）如果x的摄取（或释放）恒定，则x的输入（=流量乘以动脉浓度）=x的输出（=流量乘以静脉浓度）+x的组织代谢（其中如果有组织吸收，组织代谢项为正，如果有组织释放，则组织代谢项为负）。菲克，当然，l）提出这个方程作为测量血液流量的方法。当所有其他特征被独立测量时，该方程可以并且被用来找到任何单个特征，并且我们的目的是仅考虑其在组织代谢估计中的应用。很明显，AV 浓度差异不能等同于组织摄取（或释放），除非 flowN 恒定且已知。关于变化的说法是正确的
Inl increasing numbers investigators are ineas-uring concentrations of certain substances ill arterial and in venous blood and equating arteriovenous (AV) concentration differences obtained from simultaneous arterial and venous samples to uptake or release of the metabolite by a tissue drained by the venous system sampled. Conditions under which AV concentration differences are valid estimates of tissue metabolism are sharply limited and, although the literature does contain ample warning (eg, References 1-3), these limitatiolls seem to have been misutnderstood so often that it was thought a re-examination of the problem might be helfpul. Fundamentally, all such investigations wish to employ the Fick principle (4) which states that if: a) arterial concentration of substance x is colnstant, b) if venous concentration of x is constant, C) if blood flowv is constant and d) if uptake (or release) of x is constant, thenr, input of x (= flow-multiplied by arterial concentration)= output of x (= flow multiplied by venous concentration)+ tissue metabolism of x (where the tissue metabolism term is positive if there is tissue uptake and negative if there is tissue release).Fick, of course, l) roposed this equationas a means of measuring blool flow. The equation can be and is used to find any single characteris-tic whenever all the others are measured inde-pendentlv-, and it is our purpose to consider only its application to estimation of tissue metabolism. It is obvious immediately that AV concentrai-tion differences cannot be equated-to tissue up-take (or release) unless flowN is constant and known. It is correct to speak of changes in