+ Translate

Regulation of lactate production and utilization in rat tumors in vivo

, : Regulation of lactate production and utilization in rat tumors in vivo. Journal of Biological Chemistry 260(12): 7496-7501

These experiments were performed to determine the factor(s) that regulate lactic acid production and utilization by rat tumors in vivo. Arteriovenous differences for glucose and lactic, pyruvic, 3-OH-butyric, and acetoacetic acids were measured across "tissue-isolated" Walker 256 sarcocarcinomas and Morris 5123C hepatomas in fasted rats anesthetized with sodium pentobarbital. Twenty-six per cent of the sarcocarcinomas (n = 53) and 48% of the hepatomas (n = 29) utilized blood lactic acid. The remainder released lactic acid into the venous blood. The steady-state rate of glucose consumption was similar in both lactate-producing and lactate-utilizing tumors. The range of lactate concentrations in the blood leaving the tumors was narrower than the range of lactate concentrations in the blood entering the tumors. This difference was caused by tumor lactic acid production at low arterial lactate concentrations and tumor lactic acid utilization at high arterial lactate concentrations. Individual tumors changed from lactic acid production to lactic acid utilization in a matter of minutes in response to an increase in the arterial lactic acid concentration. Mean lactic plus pyruvic acid concentrations and lactic/pyruvic acid ratios in the tumor venous blood were 2.15 +/- 0.22 and 23.4 +/- 3.7 mM, respectively, for Walker sarcocarcinoma 256 (n = 18) and 1.28 +/- 0.13 and 48.1 +/- 5.1 mM, respectively, for hepatoma 5123C (n = 11). The results suggest: that a steady-state lactic plus pyruvic acid concentration and lactic/pyruvic acid ratio are maintained in the tumor cell cytoplasm by the active glycolytic pathway and by lactic acid dehydrogenase; that the tumor intracellular concentrations equilibrate with the arterial blood and that the tumor steady state is expressed in the tumor venous blood; and that tumor lactic acid production or utilization results from the equilibration between the variable arterial lactic acid concentration and the more constant tumor intracellular steady-state lactic acid concentration. Since the arterial lactate concentration may be less than, greater than, or equal to the intracellular steady-state concentration, an individual tumor may produce, utilize or neither produce nor utilize lactic acid.

(PDF 0-2 workdays service)

Order PDF Full Text


Click here to order any other PDF Full Text

Accession: 006288944

PMID: 3997885

PDF Full Text: Submit

Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:

Other references

Popescu, A., 1960: Mushroom growing at Popesti-Leordeni State Farm, Bucharest. Mushrooms were grown in a compost of FYM, to which 5-6 % of gypsum, 2-3 % of superphosphate and 8 % of sulfate of ammonia were added. The compost was placed in wooden trays in an underground chamber and covered after spawning with a 3: 1 sand/clay...

Cufar, Katarina, 2007: Dendrochronology and past human activity - A review of advances since 2000. Since 2000, important advances have been made worldwide in the dendrochronology of wood associated with past human activity and cultural heritage. This review summarizes this recent progress in regions with a longstanding tradition of using tree-...

Mochizuki K.; Torisaki M.; Kitano K., 1987: Effects of an intravitreal injection of cefazolin sodium on rabbit erg and vep. We studied the acute effects of an intravitreal injection of cefazolin sodium (CEZ) on the ERG and visual evoked potential (VEP) in albino and pigmented rabbits. ERG and VEP were recorded about 2 .apprx. 3 hours after injection. Responses from inj...

Davidson, Philip W.; Weiss, Bernard; Myers, Gary J.; Cory Slechta, Deborah A.; Brockel, Becky J.; Young, Edna Carter; Orlando, Mark; Loiselle, David; Palumbo, Donna; Pittelli, Randal; Sloan Reeves, Jean, 2000: Evaluation of techniques for assessing neurobehavioral development in children. A battery of tests has been designed to explore functional disabilities in children 10-12 years of age arising from adverse conditions during early development. At these ages, it becomes possible to use more complex and challenging tests than thos...

Van Cleeff, Jk; Blackberry, Ma; Blache, D.; Martin, Gb, 2003: Clarification of emu serum for peptide hormone assay using polyethylene glycol precipitation. Interference in radioimmunoassays (RIAs) was frequently encountered during endocrinological studies of the emu (Dromaius novaehollandiae). Interference was greatest when serum was cloudy or opaque. Such samples appeared seasonally, in spring and s...

Cope, E.D., 1886: Los mamiferos del voile de Mexico ya extinguidos. Contains descriptions of several new fossil Mammals which have already been diagnosed in the P. Am. Phil. Soc. xxii p. 1. There is one new species (Eschatius longirostris) described. .COPE (83). On the fossil Mammals of the valley of Mexico.

Perrella M.A.; Edell E.S.; Krowka M.J.; Cortese D.A.; Burnette J.C.Jr, 1991: Endothelium derived relaxing factor in vivo is a potent and selective endogenous vasodilator of the pulmonary circulation under basal and hypoxic conditions. American Review of Respiratory Disease 143(4 PART 2): A773

Jordan, P.; Barnish, G.; Bartholomew, R.K.; Grist, E.; Christie, J.D., 1978: Evaluation of an experimental mollusciciding programme to control Schistosoma mansoni transmission in St Lucia. In St. Lucia, the size and number of colonies of Biomphalaria glabrata were reduced after 4 years of a surveillance/treatment snail control programme using an emulsifiable concentrate of niclosamide (25% active ingredient). Surveys among the human...

Lu, Chunlin; Erickson, Harold P., 1997: Expression in Escherichia coli of the thermostable DNA polymerase from Pyrococcus furiosus. Pfu, the DNA polymerase from Pyrococcus furiosus, has the lowest error rate of any known polymerase in polymerase chain reaction (PCR) amplification. Previously the protein has been purified from P. furiosus bacterial cultures, and a recombinant f...

Miller, Tl; Wolin, Mj, 1986: Methanogens in human and animal intestinal tracts. Systematic and applied microbiology 7(2-3): 223-229