scholarly journals Evidence for a negative Pasteur effect in articular cartilage

1997 ◽  
Vol 321 (1) ◽  
pp. 95-102 ◽  
Author(s):  
Robert B. LEE ◽  
Jill P. G. URBAN
Keyword(s):  
Articular Cartilage ◽  
Glucose Uptake ◽  
Lactate Production ◽  
Pasteur Effect ◽  
Anoxic Conditions ◽  
Atp Production ◽  
Bovine Articular Cartilage ◽  
Atp Concentration ◽  
O2 Concentration ◽  
Lactate Formation

Uptake of external glucose and production of lactate were measured in freshly-excised bovine articular cartilage under O2 concentrations ranging from 21% (air) to zero (N2-bubbled). Anoxia (O2 concentration < 1% in the gas phase) severely inhibited both glucose uptake and lactate production. The decrease in lactate formation correlated closely with the decrease in glucose uptake, in a mole ratio of 2:1. This reduction in the rate of glycolysis in anoxic conditions is seen as evidence of a negative Pasteur effect in bovine articular cartilage. Anoxia also suppressed glycolysis in articular cartilage from horse, pig and sheep. Inhibitors acting on the glycolytic pathway (2-deoxy-d-glucose, iodoacetamide or fluoride) strongly decreased aerobic lactate production and ATP concentration, consistent with the belief that articular cartilage obtains its principal supply of ATP from substrate-level phosphorylation in glycolysis. Azide or cyanide lowered the ATP concentration in aerobic cartilage to approximately the same extent as did anoxia but, because glycolysis (lactate production) was also inhibited by these treatments, the importance of any mitochondrial ATP production could not be assessed. A negative Pasteur effect would make chondrocytes particularly liable to suffer a shortage of energy under anoxic conditions. Incorporation of [35S]sulphate into proteoglycan was severely curtailed by treatments, such as anoxia, which decreased the intracellular concentration of ATP.

scholarly journals Aerobic lactate production by mammary tissue

1975 ◽  
Vol 146 (1) ◽  
pp. 273-275 ◽  
Author(s):  
A R Elkin ◽  
N J Kuhn
Keyword(s):  
Glucose Uptake ◽  
Lactate Production ◽  
Mammary Glands ◽  
Mammary Tissue ◽  
Metabolic Derangement ◽  
Intact Tissue ◽  
Lactate Formation ◽  
Normal Feature

Glucose uptake and L-lactate production were measured in cell, slice and intact tissue preparations of mammary glands from late-pregnant and lactating rats. The tissues showed extensive conversion of glucose into lactate in vitro, but not in vivo. Therefore aerobic lactate formation is not a normal feature of mammary tissue, but occurs in vitro as the result of some metabolic derangement.

Oligosaccharides Derived from Bovine Articular Cartilage Keratan Sulfates after Keratanase II Digestion: Implications for Keratan Sulfate Structural Fingerprinting

Biochemistry ◽  
1994 ◽  
Vol 33 (16) ◽  
pp. 4836-4846 ◽  
Author(s):  
Gavin M. Brown ◽  
Thomas N. Huckerby ◽  
Haydn G. Morris ◽  
Beverley L. Abram ◽  
Ian A. Nieduszynski
Keyword(s):  
Articular Cartilage ◽  
Keratan Sulfate ◽  
Bovine Articular Cartilage ◽  
Keratanase Ii

Toward An MRI-Based Method to Measure Non-Uniform Cartilage Deformation: An MRI-Cyclic Loading Apparatus System and Steady-State Cyclic Displacement of Articular Cartilage Under Compressive Loading

2003 ◽  
Vol 125 (2) ◽  
pp. 180-188 ◽  
Author(s):  
C. P. Neu ◽  
M. L. Hull
Keyword(s):  
Steady State ◽  
Articular Cartilage ◽  
Pneumatic Cylinder ◽  
Cycle Duration ◽  
Steady State Response ◽  
Time Duration ◽  
Bovine Articular Cartilage ◽  
State Response ◽  
The Mean ◽  
Phantom Material

Recent magnetic resonance imaging (MRI) techniques have shown potential for measuring non-uniform deformations throughout the volume (i.e. three-dimensional (3D) deformations) in small orthopedic tissues such as articular cartilage. However, to analyze cartilage deformation using MRI techniques, a system is required which can construct images from multiple acquisitions of MRI signals from the cartilage in both the undeformed and deformed states. The objectives of the work reported in this article were to 1) design an apparatus that could apply highly repeatable cyclic compressive loads of 400 N and operate in the bore of an MRI scanner, 2) demonstrate that the apparatus and MRI scanner can be successfully integrated to observe 3D deformations in a phantom material, 3) use the apparatus to determine the load cycle necessary to achieve a steady-state deformation response in normal bovine articular cartilage samples using a flat-surfaced and nonporous indentor in unconfined compression. Composed of electronic and pneumatic components, the apparatus regulated pressure to a double-acting pneumatic cylinder so that (1) load-controlled compression cycles were applied to cartilage samples immersed in a saline bath, (2) loading and recovery periods within a cycle varied in time duration, and (3) load magnitude varied so that the stress applied to cartilage samples was within typical physiological ranges. In addition the apparatus allowed gating for MR image acquisition, and operation within the bore of an MRI scanner without creating image artifacts. The apparatus demonstrated high repeatability in load application with a standard deviation of 1.8% of the mean 400 N load applied. When the apparatus was integrated with an MRI scanner programmed with appropriate pulse sequences, images of a phantom material in both the undeformed and deformed states were constructed by assembling data acquired through multiple signal acquisitions. Additionally, the number of cycles to reach a steady-state response in normal bovine articular cartilage was 49 for a total cycle duration of 5 seconds, but decreased to 33 and 27 for increasing total cycle durations of 10 and 15 seconds, respectively. Once the steady-state response was achieved, 95% of all displacements were within ±7.42μm of the mean displacement, indicating that the displacement response to the cyclic loads was highly repeatable. With this performance, the MRI-loading apparatus system meets the requirements to create images of articular cartilage from which 3D deformation can be determined.

scholarly journals Effect of dynamic loading on the frictional response of bovine articular cartilage

2005 ◽  
Vol 38 (8) ◽  
pp. 1665-1673 ◽  
Author(s):  
Ramaswamy Krishnan ◽  
Elise N. Mariner ◽  
Gerard A. Ateshian
Keyword(s):  
Articular Cartilage ◽  
Dynamic Loading ◽  
Bovine Articular Cartilage
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