Hypometabolic homeostasis in overwintering aquatic amphibians.
Hypometabolic homeostasis in overwintering aquatic amphibians.
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越冬水生两栖动物的代谢低下稳态。
DOI：
--
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发表时间：
1997
影响因子：
2.8
通讯作者：
Timothy G. West
中科院分区：
文献类型：
--
作者：
R. Boutilier;Paul H. Donohoe;G. Tattersall;Timothy G. West
许多两栖动物每年冬天都会遇到这样的情况：它们的体温如此之低，以至于正常活动暂停，动物进入麻木状态。在被冰覆盖的池塘或湖泊中，氧气水平也可能变得有限，从而迫使动物忍受长时间的严重缺氧或缺氧。某些青蛙（如蛙）可以显着抑制其代谢缺氧，但不像其他兼性脊椎动物厌氧菌（如海龟，金鱼）的耐受性长时间的完全缺氧。然而，许多越冬的两栖动物确实能够忍受长时间的严重缺氧，完全依靠皮肤的气体交换。蛙越冬2个月在缺氧的水（PO 2约25毫米汞柱）在3摄氏度逐步减少他们的血液PCO 2的水平特征的水呼吸的鱼。其结果是，血液pH值上升，并推测通过增加血红蛋白O2-亲和力促进经皮O2转移。即使在几个月的严重缺氧后，也没有大量的乳酸盐积累，因为动物继续依赖皮肤气体交换来满足受抑制的有氧代谢的要求。我们最近的实验表明，青蛙的骨骼肌oxyconforms在体外的O2可用的量。骨骼肌氧合构象的细胞基础尚不清楚，但推动我们继续实验的假设认为，细胞水平的代谢抑制与细胞膜离子泄漏的抑制是同义词。
Many amphibians encounter conditions each winter when their body temperature is so low that normal activities are suspended and the animals enter into a state of torpor. In ice-covered ponds or lakes, oxygen levels may also become limiting, thereby forcing animals to endure prolonged periods of severe hypoxia or anoxia. Certain frogs (e.g. Rana temporaria) can dramatically suppress their metabolism in anoxia but are not as tolerant as other facultative vertebrate anaerobes (e.g. turtle, goldfish) of prolonged periods of complete O2 lack. Many overwintering amphibians do, however, tolerate prolonged bouts of severe hypoxia, relying exclusively on cutaneous gas exchange. Rana temporaria overwintering for 2 months in hypoxic water (PO2 approximately 25 mmHg) at 3 degrees C progressively reduce their blood PCO2 to levels characteristic of water-breathing fish. The result is that blood pH rises and presumably facilitates transcutaneous O2 transfer by increasing Hb O2-affinity. Even after months of severe hypoxia, there is no substantial build-up of lactate as the animals continue to rely on cutaneous gas exchange to satisfy the requirements of a suppressed aerobic metabolism. Our recent experiments have shown that the skeletal muscle of frogs oxyconforms in vitro to the amount of O2 available. The cellular basis for the oxyconformation of skeletal muscle is unknown, but the hypothesis driving our continuing experiments theories that metabolic suppression at a cellular level is synonymous with suppressed ion leak across cellular membranes.
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DOI：
--
发表时间：
1991-09
期刊：
The Journal of experimental biology
影响因子：
--
作者：
S. C. Wood;G. Malvin
通讯作者：
S. C. Wood;G. Malvin
DOI：
10.1016/s0021-9258(20)64292-2
发表时间：
1991-03
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
M. Harrison;P. Rathinavelu;P. Arese;R. Geahlen;P. Low
通讯作者：
M. Harrison;P. Rathinavelu;P. Arese;R. Geahlen;P. Low
影响因子：
56.9
作者：
J. Weiss;S. Lamp
通讯作者：
J. Weiss;S. Lamp
缺氧和酸中毒联合作用下龟心脏组织的力和酸碱状态。
DOI：
10.1152/ajpregu.1990.259.1.r15
发表时间：
1990
期刊：
The American journal of physiology
影响因子：
--
作者：
Wasser,JS;Freund,EV;Gonzalez,LA;Jackson,DC
通讯作者：
Jackson,DC
维持高细胞外 pH 值不会影响水下缺氧牛蛙的细胞 pH 值或新陈代谢。
DOI：
10.1002/jez.1402650603
发表时间：
1993
期刊：
The Journal of experimental zoology
影响因子：
--
作者：
Wasser,JS;Jackson,DC;Chang,SY;Warburton,SJ
通讯作者：
Warburton,SJ