Catecholamine secretion by chemical hypoxia in guinea-pig, but not rat, adrenal medullary cells: differences in mitochondria.
Catecholamine secretion by chemical hypoxia in guinea-pig, but not rat, adrenal medullary cells: differences in mitochondria.
复制标题
豚鼠而非大鼠肾上腺髓质细胞化学缺氧导致的儿茶酚胺分泌：线粒体的差异。
DOI：
10.1016/j.neuroscience.2015.05.080
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发表时间：
2015
期刊：
影响因子：
3.3
通讯作者：
Inoue M
中科院分区：
文献类型：
--
作者：
Harada K;Endo Y;Warashina A;Inoue M
线粒体抑制剂（CN-，复合物IV抑制剂和CCCP，质子载体）对儿茶酚胺（CA）分泌和线粒体功能的影响在大鼠和豚鼠肾上腺嗜铬细胞中进行了功能和生化研究。豚鼠嗜铬细胞对CN-或CCCP有显著的分泌CA的反应，但大鼠细胞对它们中的任何一种都表现出很小的分泌反应。大鼠肾上腺髓质的静息代谢率与豚鼠肾上腺髓质无差异。另一方面，豚鼠嗜铬细胞对CN−的反应的线粒体膜电位（Δ Δ m）的去极化时间过程比大鼠嗜铬细胞慢，这种差异被F1 F0-ATP酶抑制剂寡霉素消除。CCCP诱导的豚鼠嗜铬细胞中细胞ATP减少的程度（使用Mg 2+指示剂间接测量）小于大鼠嗜铬细胞。F1 F0-ATP酶抑制因子在豚鼠肾上腺髓质的相对表达量低于大鼠肾上腺髓质，而F1 F0-ATP酶α亚基的相对表达量则相反。结果表明，豚鼠嗜铬细胞对线粒体抑制剂的敏感性高于大鼠嗜铬细胞，这是由于在Δ ATP去极化的条件下，F1 F0-ATP酶的反向操作程度更大，从而导致ATP减少所致。
The effects of mitochondrial inhibitors (CN−, a complex IV inhibitor and CCCP, protonophore) on catecholamine (CA) secretion and mitochondrial function were explored functionally and biochemically in rat and guinea-pig adrenal chromaffin cells. Guinea-pig chromaffin cells conspicuously secreted CA in response to CN−or CCCP, but rat cells showed a little, if any, secretory response to either of them. The resting metabolic rates in rat adrenal medullae did not differ from those in guinea-pig adrenal medullae. On the other hand, the time course of depolarization of the mitochondrial membrane potential (ΔΨm) in guinea-pig chromaffin cells in response to CN−was slower than that in rat chromaffin cells, and this difference was abolished by oligomycin, an F1F0-ATPase inhibitor. The extent of CCCP-induced decrease in cellular ATP in guinea-pig chromaffin cells, which was indirectly measured using a Mg2+indicator, was smaller than that in rat chromaffin cells. Relative expression levels of F1F0-ATPase inhibitor factor in guinea-pig adrenal medullae were smaller than in rat adrenal medullae, and the opposite was true for F1F0-ATPase α subunit. The present results indicate that guinea-pig chromaffin cells secrete more CA in response to a mitochondrial inhibitor than rat chromaffin cells and this higher susceptibility in the former is accounted for by a larger extent of reversed operation of F1F0-ATPase with the consequent decrease in ATP under conditions where ΔΨmis depolarized.