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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.

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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...

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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