Changes in the ultrastructure of intervertebrate disc cells under the influence of dynamic loads in age-related aspects

The article considers the problem of the damaging effect of prolonged dynamic loads on the intervertebral disc at different age periods. The study was performed on male Wistar rats of three age groups. Dynamic loads were created by running on a horizontal treadmill. Using histochemical methods, an analysis of changes in the activity of lactate dehydrogenase isoenzymes in the cells of the intervertebral discs of Wistar rats after 20-day and 90-day experimental running was carried out. Histochemical methods revealed changes in the activity of lactate dehydrogenase isoenzymes in the cells of the intervertebral discs at prolonged dynamic loads at different age periods. Damage to intervertebral disc tissues is a prerequisite for damage to the motor spinal segment as a whole. Therefore, the obtained indicators of lactate dehydrogenase activity, namely its isoenzymes, can serve as a histochemical test for objective assessment of the degree of damaging effect of prolonged dynamic load on fibrous cartilage in different age periods. The analysis showed that dynamic loading contributes to biochemical changes in the activity of lactate dehydrogenase isoenzymes in intervertebral disc cells. It was experimentally established that changes in the activity of lactate dehydrogenase isoenzymes depend on the age of the animals and the duration of dynamic loads. A decrease in the activity of LDH-1 and LDH-2 isoenzymes in the cells of the intervertebral disc was noted, but an increase in the activity of LDH-3 and LDH-4 isoenzymes.