St-Pierre 2000 Am J Physiol Regul Integr Comp Physiol: Difference between revisions
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|journal=Am J Physiol Regul Integr Comp Physiol | |journal=Am J Physiol Regul Integr Comp Physiol | ||
|abstract=This study examined whether the steady-state hypometabolism seen in overwintering frogs (Rana temporaria) is reflected at the mitochondrial level either by a reduction in their resting (state 4) and active (state 3) respiration rates and/or by increases in O<sub>2</sub> affinity. We isolated mitochondria from the skeletal muscle of cold-submerged frogs at different stages during their hibernation in normoxic and hypoxic water. A modest metabolic depression at the whole animal level (normoxic submergence) was not associated with a reduction in mitochondrial state 4 and state 3 respiration rates. However, mitochondria isolated from frogs that were submerged for 1 mo manifested an increase in their O<sub>2</sub> affinity compared with controls and with animals submerged for 4 mo. Hypometabolism was more pronounced at the whole animal level during hypoxic submergence and was accompanied by 1) a reduction in mitochondrial state 4 and state 3 rates and 2) an increase in the O<sub>2</sub> affinity of mitochondria. These findings demonstrate that metabolic depression can be reflected at all levels of biological organization in hypoxia-tolerant animals. | |abstract=This study examined whether the steady-state hypometabolism seen in overwintering frogs (''Rana temporaria'') is reflected at the mitochondrial level either by a reduction in their resting (state 4) and active (state 3) respiration rates and/or by increases in O<sub>2</sub> affinity. We isolated mitochondria from the skeletal muscle of cold-submerged frogs at different stages during their hibernation in normoxic and hypoxic water. A modest metabolic depression at the whole animal level (normoxic submergence) was not associated with a reduction in mitochondrial state 4 and state 3 respiration rates. However, mitochondria isolated from frogs that were submerged for 1 mo manifested an increase in their O<sub>2</sub> affinity compared with controls and with animals submerged for 4 mo. Hypometabolism was more pronounced at the whole animal level during hypoxic submergence and was accompanied by 1) a reduction in mitochondrial state 4 and state 3 rates and 2) an increase in the O<sub>2</sub> affinity of mitochondria. These findings demonstrate that metabolic depression can be reflected at all levels of biological organization in hypoxia-tolerant animals. | ||
|keywords=Frog, Hypoxia, State 3, State 4, P50 | |keywords=Frog, Hypoxia, State 3, State 4, P50 | ||
|articletype=Protocol; Manual | |articletype=Protocol; Manual | ||
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{{Labeling | {{Labeling | ||
|taxonomic group=Amphibians | |||
|preparations=Isolated Mitochondria | |||
|injuries=Hypoxia | |||
|instruments=Oxygraph-2k | |instruments=Oxygraph-2k | ||
|articletype=Protocol; Manual | |articletype=Protocol; Manual | ||
}} | }} | ||
Revision as of 18:37, 8 August 2013
| St-Pierre J, Tattersall GJ, Boutilier RG (2000) Metabolic depression and enhanced O2 affinity of mitochondria in hypoxic hypometabolism. Am J Physiol Regul Integr Comp Physiol 279: R1205-R1214. |
St-Pierre J, Tattersall GJ, Boutilier RG (2000) Am J Physiol Regul Integr Comp Physiol
Abstract: This study examined whether the steady-state hypometabolism seen in overwintering frogs (Rana temporaria) is reflected at the mitochondrial level either by a reduction in their resting (state 4) and active (state 3) respiration rates and/or by increases in O2 affinity. We isolated mitochondria from the skeletal muscle of cold-submerged frogs at different stages during their hibernation in normoxic and hypoxic water. A modest metabolic depression at the whole animal level (normoxic submergence) was not associated with a reduction in mitochondrial state 4 and state 3 respiration rates. However, mitochondria isolated from frogs that were submerged for 1 mo manifested an increase in their O2 affinity compared with controls and with animals submerged for 4 mo. Hypometabolism was more pronounced at the whole animal level during hypoxic submergence and was accompanied by 1) a reduction in mitochondrial state 4 and state 3 rates and 2) an increase in the O2 affinity of mitochondria. These findings demonstrate that metabolic depression can be reflected at all levels of biological organization in hypoxia-tolerant animals. • Keywords: Frog, Hypoxia, State 3, State 4, P50
Labels:
Stress:Hypoxia
Preparation: Isolated Mitochondria"Isolated Mitochondria" is not in the list (Intact organism, Intact organ, Permeabilized cells, Permeabilized tissue, Homogenate, Isolated mitochondria, SMP, Chloroplasts, Enzyme, Oxidase;biochemical oxidation, ...) of allowed values for the "Preparation" property.
HRR: Oxygraph-2k
