The dynamics of morphological changes of structural components of the intervertebral disc at the end of the thirty-fifth and forty-second days while applying the experimental opioid impact

Background. According to the WHO, the diseases of the musculoskeletal system, which cause disability and mortality, rank fourth in the world following cardiovascular disease, cancer and diabetes. Due to the statistics, every fifth person suffers from back pain. Chronic diseases of musculoskeletal system are also one of the most urgent problems in Ukraine, and about 3.5 million people encountered the problem of musculoskeletal system. Objective. The aim of the study was to investigate the impact of opioids on changes of structural components of the intervertebral disc at the end of the fifth and sixth weeks of the experiment. Methods. The materials of the study were 32 sexually mature, outbred male rats, weighing from 125 to 135 g, aged 4.5 months. Animals were injected with nalbuphine intramuscularly daily in the same intervals (at 10-11 am) for 42 days. This aim was achieved by using microscopic techniques of visualization of cellular components of the rat’s intervertebral disc. Histological specimens were prepared according to the common methods using the dye hematoxylin, eosin, azan according to Heidenhain method, PAS reaction according to McManus and Alcian blue according to Steedman. Results. As a result of experimental opioid exposure for 35 and 42 days, we discovered that in 35 days the gelatinous nucleus was reduced and deformed. Notochondral cells were rare. Mostly cell-free zones with a somewhat compacted matrix were localized in the gelatinous nucleus. In 42 days, there were significant structural changes in the gelatinous nucleus, as well as in the structural elements of the fibrous ring and cartilaginous locking plates. The amount of notochondral cells was reduced. The cytoplasm of some notochondral cells was compacted. Conclusion. Pathomorphological changes in the structural components of the intervertebral disc while applying the experimental opioid effect at the end of the 35th and 42nd days will serve as a basis for further study and comparison of the manifestations of opioid chondropathy in the longer periods applying experimental opioid impact.