+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Lactate efflux is unrelated to intracellular oxygen tension in a working red muscle in situ

, : Lactate efflux is unrelated to intracellular oxygen tension in a working red muscle in situ. Journal of Applied Physiology 61(2): 402-408

Blood flow, lactate extraction, and tissue lactate concentration were measured in an autoperfused pure red muscle (dog gracilis). Muscles were frozen in situ during steady-twitch contraction at frequencies of 1-8 Hz [10-100% of maximum O2 consumption (.ovrhdot.VO2max)]. Myoglobin saturation was determined spectrophotometrically with subcellular spatial resolution. Intracellular PO2 (PtO2) was calculated from the oxymyoglobin-dissociation curve. Tissue lactate was well correlated with .ovrhdot.VO2 but not with PtO2. Lactate efflux increased markedly above a threshold work rate near 50% .ovrhdot.VO2max. Efflux was neither linearly correlated with tissue lactate nor related to PtO2. PtO2 exceeded the minimum PO2 for maximal .ovrhdot.VO2 in each of 2,000 cells examined in muscles frozen at 1-6 Hz. A small population of anoxic cells was found in three muscles at 8 Hz, but lactate efflux from these muscles was not greater than from six other muscles at 8 Hz. Our conclusions are that 1) the concept of an anaerobic threshold does not apply to red muscle and 2) in absence of anoxia neither tissue lactate nor blood lactate can be used to impute muscle O2 availability or glycolytic rate. A mechanism by which the blood-tissue lactate gradient could support aerobic metabolism is discussed.


Other references

Valdes, A.; Cazanave, C.; Dabis, F.; Neau, D.; Lacoste, D.; Gaborieau, V.; Farbos, S.; Dworkin, M.S., 2017: Knowledge, behaviors, and attitudes of HIV-infected men about syphilis. To explore knowledge on syphilis, sexual behaviors, and attitudes in men living with HIV in southwestern France. In the ANRS CO3 Aquitaine Cohort of people living with HIV (PLHIV), a self-administered questionnaire was proposed to all male PLHIV a...

Grunwald, M.H.; David, M.; Ginzburg, A.; Feuerman, E.J., 1984: Pemphigus vulgaris with a high titer of antinuclear antibodies. Archives of Dermatology 120(8): 996-996

Platt S.G.; Yang N S., 1987: Dot assay for neomycin phosphotransferase activity in crude cell extracts. A dot assay for determining neomycin phosphotransferase (NPT II) activity in crude cell extracts has been developed. The assay provides for the rapid screening of large numbers of cell cultures generated in gene transformation experiments using NP...

Held, T.; Kummer, R.; Marti, B., 1997: Heart rate, blood lactate level and perceived exertion during submaximal running: New nomograms for the estimation of endurance capacity. Considering the protective effect of physical activity against coronary heart disease, the estimation of endurance capacity is not only recommended for sportsmen but is also useful for exercise counselling of unfit persons. Endurance capacity can...

Konturek, J.W.; Dembiński, A.; Konturek, S.J.; Domschke, W., 1997: Helicobacter pylori and gastric adaptation to repeated aspirin administration in humans. The gastric irritant properties of nonsteroidal anti-inflammatory drugs (NSAID) are well established but the pathogenic mechanisms by which these agents damage the mucosa or delay its repair are poorly understood. The phenomenon of gastric adaptat...

Townsend, M.K.; Bao, Y.; Poole, E.M.; Bertrand, K.A.; Kraft, P.; Wolpin, B.M.; Clish, C.B.; Tworoger, S.S., 2016: Impact of Pre-analytic Blood Sample Collection Factors on Metabolomics. Many epidemiologic studies are using metabolomics to discover markers of carcinogenesis. However, limited data are available on the influence of pre-analytic blood collection factors on metabolite measurement. We quantified 166 metabolites in arch...

Rodriguez Batista, Daysi., 2000: Recaptures of two Neotropical migrant birds in Cuba Recaptura de dos aves migratorias neotropicales en Cuba. Pitirre. Spring; 131: 22

Sekowska, A.; Gospodarek, E., 2008: Hydrophobic and hemagglutinating properties of Klebsiella pneumoniae and Klebsiella oxytoca. The aim of this study was to estimated hydrophobic and hemnagglutinating properties of Klebsiella pneumoniae and Klebsiella oxytoca rods. The hydrophobcity was evaluated according to the method of Rosenberg et al. The hemagglutinating properties w...

Panlian, R., 1942: La larve de Rhyssemodes orientalis Muls. et God. (Col. Scarabaeidae). Bulletin de la Societe Entomologique de France Paris, 47: 129-131

Vachalkova A., 1973: Electrochemical properties of poly cyclic compounds studied by the polarographic method in anhydrous systems part 1 comparison of half wave potentials of carcinogenic and noncarcinogenic hydro carbons in di methyl formamide and di methyl sulfoxide. Neoplasma (bratislava): 631-641