THE INTRAMITOCHONDRIAL VOLUME MEASURED USING SUCROSE AS AN EXTRA-MITOCHONDRIAL MARKER OVERESTIMATES THE TRUE MATRIX VOLUME DETERMINED WITH MANNITOL
THE INTRAMITOCHONDRIAL VOLUME MEASURED USING SUCROSE AS AN EXTRA-MITOCHONDRIAL MARKER OVERESTIMATES THE TRUE MATRIX VOLUME DETERMINED WITH MANNITOL
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DOI：
10.1042/bj2140387
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发表时间：
1983-01-01
影响因子：
4.1
通讯作者：
QUINLAN, PT
中科院分区：
文献类型：
--
作者：
HALESTRAP, AP;QUINLAN, PT
基质体积的分离[大鼠]肝脏和心脏线粒体估计在各种渗透压和各种渗透支持使用36 Cl-和[14 C]蔗糖，D-甘露醇，D-3-甲氧基葡萄糖和胆碱作为extramoditrial标记。3-甲氧基葡萄糖的使用仅在0 ℃下是可能的。C，因为它在生理温度下进入线粒体。使用的所有extramitoditrile标记物给出了表观基质体积对渗透压的倒数的线性图，但当使用蔗糖时，该图的斜率大于其他extramitoditrile标记物。当外推至无限渗透压时，当使用甘露醇时平均基质体积为零，但对于蔗糖和Cl-，平均基质体积为约0.6 μ l/mg蛋白质，而当使用胆碱时，平均基质体积为-0.4 μ l/mg蛋白质。在生理渗透压（约330 m-dl）下，使用甘露醇估计的KCl培养基中去能肝线粒体的平均基质体积为0.46 μ l/mg蛋白质，而使用蔗糖获得的平均基质体积为1.68 μ l/mg蛋白质。甘露醇，胆碱和蔗糖培养基中的值相似时，甘露醇，但不是蔗糖作为线粒体外标记。有人认为，3H2O/[14 C]甘露醇空间比3H2O/[14 C]蔗糖空间更准确地反映了真实的线粒体基质体积。的质子动力和代谢产物的intramitochondrial浓度的测量这一后果进行了讨论。
The matrix volume of isolated [rat] liver and heart mitochondria was estimated at various osmolarities and in various osmotic supports using 36Cl- and [14C]sucrose, D-mannitol, D-3-methoxyglucose and choline as extramitochondrial markers. The use of 3-methoxyglucose was only possible at 0.degree. C since it entered mitochondria at physiological temperatures. All extramitochondrial markers used gave linear plots of apparent matrix volume against the reciprocal of the osmolarity, but the slope of this plot was greater when sucrose was used than with the other extramitochondrial markers. When extrapolated to infinite osmolarity the mean matrix volume was zero when mannitol was used, but about 0.6 .mu.l/mg of protein for sucrose and Cl- and -0.4 .mu.l/mg of protein when choline was used. At physiological osmolarity (about 330 m-osmol) the mean matrix volume of de-energized liver mitochondria in KCl medium estimated using mannitol was 0.46 .mu.l/mg of protein, whereas that obtained using sucrose was 1.68 .mu.l/mg of protein. Values in mannitol, choline and sucrose media were similar when mannitol, but not sucrose was used as extramitochondrial marker. It is argued that the 3H2O/[14C]mannitol space more accurately reflects the true mitochondrial matrix volume than does the 3H2O/[14C]sucrose space. The consequences of this for measurements of the protonmotive force and the intramitochondrial concentration of metabolites are discussed.