Buttgereit F, Brand M D, Müller M
Department of Internal Medicine, Humboldt University (Charité), Berlin, Germany.
Biosci Rep. 1992 Oct;12(5):381-6. doi: 10.1007/BF01121501.
The influence of ConA on the energy metabolism of quiescent rat thymocytes was investigated by measuring the effects of inhibitors of protein synthesis, proteolysis, RNA/DNA synthesis, Na+K(+)-ATPase, Ca(2+)-ATPase and mitochondrial ATP synthesis on respiration. Only about 50% of the coupled oxygen consumption of quiescent thymocytes could be assigned to specific processes using two different media. Under these conditions the oxygen is mainly used to drive mitochondrial proton leak and to provide ATP for protein synthesis and cation transport, whereas oxygen consumption to provide ATP for RNA/DNA synthesis and ATP-dependent proteolysis was not measurable. The mitogen ConA produced a persistent increase in oxygen consumption by about 30% within seconds. After stimulation more than 80% of respiration could be assigned to specific processes. The major oxygen consuming processes of ConA-stimulated thymocytes are mitochondrial proton leak, protein synthesis and Na+K(+)-ATPase with about 20% each of total oxygen consumption, while Ca(2+)-ATPase and RNA/DNA synthesis contribute about 10% each. Quiescent thymocytes resemble resting hepatocytes in that most of the oxygen consumption remains unexplained. In contrast, the pattern of energy metabolism in stimulated thymocytes is similar to that described for Ehrlich Ascites tumour cells and splenocytes, which may also be in an activated state. Most of the oxygen consumption is accounted for, so the unexplained process(es) in unstimulated cells shut(s) off on stimulation.
通过测量蛋白质合成、蛋白水解、RNA/DNA合成、钠钾ATP酶、钙ATP酶和线粒体ATP合成的抑制剂对呼吸的影响，研究了刀豆球蛋白A（ConA）对静止大鼠胸腺细胞能量代谢的影响。使用两种不同的培养基，静止胸腺细胞耦合氧消耗中只有约50%可归因于特定过程。在这些条件下，氧气主要用于驱动线粒体质子泄漏，并为蛋白质合成和阳离子转运提供ATP，而用于为RNA/DNA合成和ATP依赖性蛋白水解提供ATP的氧消耗无法测量。促有丝分裂原ConA在数秒内使氧消耗持续增加约30%。刺激后，超过80%的呼吸可归因于特定过程。ConA刺激的胸腺细胞的主要耗氧过程是线粒体质子泄漏、蛋白质合成和钠钾ATP酶，各占总氧消耗的约20%，而钙ATP酶和RNA/DNA合成各贡献约10%。静止胸腺细胞与静止肝细胞相似，即大部分氧消耗仍无法解释。相比之下，刺激后胸腺细胞的能量代谢模式与艾氏腹水肿瘤细胞和脾细胞相似，后者也可能处于激活状态。大部分氧消耗得到了解释，因此未刺激细胞中无法解释的过程在刺激时停止。
