Basic cell metabolism of articular cartilage. Manometric studies.

摘要: Basic metabolism generates energy by the anaerobic or aerobic metabolization of glucose. The articular cartilage obtains substrate and oxygen from synovial fluid. Their concentrations within diminish with increasing proximity to basal layer at bone-cartilage boundary. gradients depend upon cell density consumption cells. gradient partial pressure (PO2) could provide conditions for Pasteur effect, which, however, has not yet been clearly observed. Metabolic reactions chondrocytes positive negative glucose have hitherto examined, are object present study. (QO2) in pig femoral heads was measured manometrically (Warburg technique) absence its presence 1.25 10.0 mM. There a close correlation between QO2 concentration having nature glucose-induced respiratory suppression (Crabtree effect). glucose, which did rise proportion concentration, exceed 15.7 mumol/gdw/h. maximum lactate production 20 23 mumol/gdw/h attained 5 mM showed no further increase higher concentrations. This stoichiometric "lactate deficiency" means that absorbed but glycolyzed is channeled into synthesizing storage processes. In glucose-free incubation, despite conditions, utilized only unphysiologically high greater than 10 Potassium cyanide reduced 80-90% as sign activity non-mitochondrial oxidases. With monoiodoacetate (MIA), respiration fell dramatically during 4 h substrate-free incubation. It can be concluded results that, under physiological level synovia reduces well-glucose-supplied upper cartilage, thus allowing an oxidative compensation diminishing glycolysis zone. Crabtree demonstrated first time chondrocytes, seems role essential regulatory mechanism basic cartilage.