Abstract
Objective: To develop and use a closed chamber to study the metabolism of isolated disc cells under controlled conditions such as reduced pH.
Design: Disc cells were incubated in the chamber for four hours, while embedded electrodes measured pH and pO2. A port allowed sampling.
Subjects: Nucleus pulposus cells were isolated from the coccygeal discs of 33 steers (18–24 months old), within three hours of slaughter.
Outcome measures: Metabolic rates were calculated from concentration changes. Cell viability was assesed on completion.
Results: At pH 7.4, metabolic rates were similar to those measured in tissue [1, 2] with lactic acid production and oxygen consumption rates of 157 and 12 nmol/million cells/hour respectively, and a 1: 2 ratio of glucose consumption: lactic acid production. Lactic acid production and oxygen consumption fell with extracellular pH, to 89 and 65 nmol/million cells/hour (lactate) and 8 and 5 nmol/million cells/hour (oxygen), at pH 6.7 and pH 6.2 respectively.
Conclusions: These results show a fall in lactic acid production and oxygen consumption with extracellular acid-ification. There is a complex interplay between different components of the nutritional environment. Investigating these in combination should give valuable information about disc cell metabolism, as changes can affect nutrient availability and hence cellular activity, viability, and matrix production rates.
Abstracts prepared by Mr. A. J. Stirling, FRCS, and Miss A. Weaver. Correspondence should be addressed to Miss A. Weaver at the Research and Teaching Centre, Royal Orthopaedic Hospital, Northfield, Birmingham, B31 2AP, UK
BritSpine 2002, the second combined meeting of the British Association of Spinal Surgeons, the British Cervical Spine Society, The British Scoliosis Society and the Society for Back Pain Research, took place at the International Convention Centre in Birmingham UK between 27th February and 1st March 2002. The following presentations and posters were given and displayed.
This work is funded by the EPSRC
References:
1 Holm, S et al. 1981. Nutrition of the intervertberal disc: Solute transport and metabolism. Conn Tiss Res, 8: 101–119. Google Scholar
2 Ishihara H, Urban JPG. Effects of low oxygen concentrations and metabolic inhibitors on proteoglycan and protein synthesis rates in the intervertebral disc. J Orthop Res, 17: 829–835 Google Scholar
