Kinetics of oxygen consumption and light-induced changes of nucleotides in solitary rod photoreceptors.
Kinetics of oxygen consumption and light-induced changes of nucleotides in solitary rod photoreceptors.
复制标题
孤杆光感受器中耗氧量和光诱导核苷酸变化的动力学。
DOI：
10.1085/jgp.108.2.75
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Cornwall,MC
中科院分区：
文献类型：
--
作者：
Poitry,S;Tsacopoulos,M;Fein,A;Cornwall,MC
我们同时测量光诱导的变化率的耗氧率（QO 2）和跨膜电流的单个蝾螈杆光感受器。由于PO 2的变化被2 mM Amytal（一种线粒体呼吸抑制剂）抑制，我们得出结论，它是线粒体起源的。为了确定QO 2变化的原因，我们在一批棒中测量了ATP和磷酸肌酸（PCr）的浓度。光照3分钟后，当QO 2下降约25%时，ATP水平没有显著变化;相反，PCr的量下降约40%。我们的结论是，无论是光诱导的QO 2的降低不是由增加[ATP]或[PCr]，或光诱导的变化[PCr]是高度异质性的杆细胞。
We made simultaneous measurements of light-induced changes in the rate of oxygen consumption (QO2) and transmembrane current of single salamander rod photoreceptors. Since the change of PO2 was suppressed by 2 mM Amytal, an inhibitor of mitochondrial respiration, we conclude that it is mitochondrial in origin. To identify the cause of the change of QO2, we measured, in batches of rods, the concentrations of ATP and phosphocreatine (PCr). After 3 min of illumination, when the QO2 had decreased approximately 25%, ATP levels did not change significantly; in contrast, the amount of PCr had decreased approximately 40%. We conclude that either the light-induced decrease of QO2 is not caused by an increase in [ATP] or [PCr], or that the light-induced change of [PCr] is highly heterogeneous in the rod cell.