O2 consumption, aerobic glycolysis and tissue phosphagen content during activation of the Na+/K+ pump in rat portal vein
(1984) In Pflügers Archiv 401(2). p.119-124- Abstract
- Oxygen consumption, lactate production and tissue contents of ATP, phosphocreatine (PCr) and lactate were measured following readdition of K+ to K+-depleted rat portal veins, in order to study the energy turnover associated with Na+/K+ pumping. During incubation in K+-free medium at 37 degrees C spontaneous contractions disappeared in 10-20 min. Readdition of K+ (5.9 mM) after 40 min K+-free incubation caused hyperpolarization of the cell membrane for the first 5-10 min and then gradual depolarization with return of spontaneous action potentials and contractions by 10-20 min. During the first 4-6 min after K+ readdition aerobic lactate production was about doubled and then gradually returned to the original level (0.17 mumol/min g) at... (More)
- Oxygen consumption, lactate production and tissue contents of ATP, phosphocreatine (PCr) and lactate were measured following readdition of K+ to K+-depleted rat portal veins, in order to study the energy turnover associated with Na+/K+ pumping. During incubation in K+-free medium at 37 degrees C spontaneous contractions disappeared in 10-20 min. Readdition of K+ (5.9 mM) after 40 min K+-free incubation caused hyperpolarization of the cell membrane for the first 5-10 min and then gradual depolarization with return of spontaneous action potentials and contractions by 10-20 min. During the first 4-6 min after K+ readdition aerobic lactate production was about doubled and then gradually returned to the original level (0.17 mumol/min g) at about 20 min. The increase in glycolytic rate was prevented by 1 mM ouabain. In contrast, O2 consumption (in K+-free medium, 0.38 mumol/min g) rose by about 10% when K+ was added and this increase lasted about 5 min. By 8 min after K+ addition the increased glycolysis and oxidative phosphorylation had accounted for each about the same amount of extra ATP generation over that extrapolated from the steady rate before K+ addition. The average total increase in ATP turnover in the first 8 min was 15%. During this period there was no change in the cellular content of ATP, PCr, or extractable ADP. The results indicate that Na+/K+ pumping utilizes a relatively small share of the total energy turnover in the vascular smooth muscle but is to a large extent dependent on aerobic glycolysis and therefore a major site of carbohydrate usage. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1103286
- author
- Hellstrand, Per LU ; Jorup, Carin and Lydrup, Marie-Louise
- organization
- publishing date
- 1984
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Vascular smooth muscle, Na+/K+ pump- O2 consumption, Glycolysis, Membrane potential
- in
- Pflügers Archiv
- volume
- 401
- issue
- 2
- pages
- 119 - 124
- publisher
- Springer
- external identifiers
-
- pmid:6089095
- scopus:0021445273
- ISSN
- 0031-6768
- DOI
- 10.1007/BF00583871
- language
- English
- LU publication?
- yes
- id
- 39f7096f-3f57-43ec-8f70-6ff3f49d19a7 (old id 1103286)
- date added to LUP
- 2016-04-01 16:26:01
- date last changed
- 2021-01-03 03:04:47
@article{39f7096f-3f57-43ec-8f70-6ff3f49d19a7, abstract = {{Oxygen consumption, lactate production and tissue contents of ATP, phosphocreatine (PCr) and lactate were measured following readdition of K+ to K+-depleted rat portal veins, in order to study the energy turnover associated with Na+/K+ pumping. During incubation in K+-free medium at 37 degrees C spontaneous contractions disappeared in 10-20 min. Readdition of K+ (5.9 mM) after 40 min K+-free incubation caused hyperpolarization of the cell membrane for the first 5-10 min and then gradual depolarization with return of spontaneous action potentials and contractions by 10-20 min. During the first 4-6 min after K+ readdition aerobic lactate production was about doubled and then gradually returned to the original level (0.17 mumol/min g) at about 20 min. The increase in glycolytic rate was prevented by 1 mM ouabain. In contrast, O2 consumption (in K+-free medium, 0.38 mumol/min g) rose by about 10% when K+ was added and this increase lasted about 5 min. By 8 min after K+ addition the increased glycolysis and oxidative phosphorylation had accounted for each about the same amount of extra ATP generation over that extrapolated from the steady rate before K+ addition. The average total increase in ATP turnover in the first 8 min was 15%. During this period there was no change in the cellular content of ATP, PCr, or extractable ADP. The results indicate that Na+/K+ pumping utilizes a relatively small share of the total energy turnover in the vascular smooth muscle but is to a large extent dependent on aerobic glycolysis and therefore a major site of carbohydrate usage.}}, author = {{Hellstrand, Per and Jorup, Carin and Lydrup, Marie-Louise}}, issn = {{0031-6768}}, keywords = {{Vascular smooth muscle; Na+/K+ pump- O2 consumption; Glycolysis; Membrane potential}}, language = {{eng}}, number = {{2}}, pages = {{119--124}}, publisher = {{Springer}}, series = {{Pflügers Archiv}}, title = {{O2 consumption, aerobic glycolysis and tissue phosphagen content during activation of the Na+/K+ pump in rat portal vein}}, url = {{http://dx.doi.org/10.1007/BF00583871}}, doi = {{10.1007/BF00583871}}, volume = {{401}}, year = {{1984}}, }