Морфологія міжхребцевого диска та кісткової тканини апофізів тіл хребців в умовах моделювання остеопорозу

Abstract

У статті представлено результати дослідження, що проведені на 10 щурах, на терміни 1 і 3 міс. після моделювання остеопорозу шляхом оваріоектомії. З використанням гістологічних методів і морфометрії вивчали стан кісткової тканини апофізів тіл хребців і структури міжхребцевого диска – фіброзне кільце і драглисте ядро. Виявлено, що на ранні терміни дослідження в міжхребцевих дисках і прилеглої кісткової тканини тіл хребців розвиваються деструктивні зміни. У міжхребцевих дисках деструктивні зміни в матриксі і клітинах були практично ідентичні за показниками оцінки в балах (3,07 + 0,25) і (2,8 + 0,2). У матриксі кісткових трабекул деструктивні зміни були більш виражені в порівнянні з клітинами (4,67 + 0,23) і (3,67 + 0,21) балів (Р <0,01). У разі порівняння двох систем – кісткової тканини і міжхребцевого диска – деструктивні зміни в 1,4 рази були більш виражені в кістковій тканині; В статье представлены результаты исследования, проведенные на 10 крысах, на сроки 1 и 3 мес. после моделирования остеопороза путем овариоэктомии. С использованием гистологических методов и морфометрии изучали состояние костной ткани апофизов тел позвонков и структуры межпозвонкового диска – фиброзное кольцо и студенистое ядро. Выявлено, что на ранние сроки исследования в межпозвонковых дисках и прилегающей костной ткани тел позвонков развиваются деструктивные изменения. В межпозвонковых дисках деструктивные изменения в матриксе и клетках были практически идентичныьпо показателям оценки в баллах (3,07 + 0,25) и (2,8 + 0,2). В матриксе костных трабекул деструктивные изменения были более выражены по сравнению с клетками (4,67 + 0,23) и (3,67 + 0,21) баллов (Р <0,01). При сравнении двух систем: деструктивные изменения костной ткани в 1,4 раза превышали нарушения в межпозвонковых дисках; Osteochondrosis of the spine is one of the common chronic diseases in humans. However, histological studies regarding changes in the intervertebral disc, depending on the state of adjacent bone tissue, in particular bone tissue of apothisis is not found, however these structures are associated with metabolism. The purpose of the study is to investigate the changes in the structure of the intervertebral disc in the correlation with the adjacent bone tissue of vertebrate bodies in the stages of the development of osteoporosis induced by ovariectomy in an animal experiment. Object and methods. Osteoporosis was simulated on white laboratory rats by ovariectomy. Animals were killed after 1 and 3 months after surgery. For histological examination, 10 rats had their intervertebral discs isolated with adjacent vertebral bodies. A morphometric analysis was performed on the indicators of the state of the matrix and bone marrow cells and between the vertebral disk. In animals, unlike humans, the growth zone is located in the body of the vertebrae and separated from the intervertebral disk by a layer of bone tissue through which the nutrition of the disk passes. Therefore, in this study, the object was the bone layer between the growth zone and the intervertebral disc. Results of research. In 1 month after ovariectomy the expressed destructive changes in the investigated structures were not revealed. The bone had signs of reactive reorganization with uneven layers on areas of newly formed bone tissue and unevenly stained matrix. The intertrabucular spaces were narrow and filled with red bone marrow. In the intervertebral disk the nucleus pulposus was slightly expanded with signs of destruction in the regional divisions. The cells formed syncytia, but isolated fibrous structures and single cells were present. The annulus fibrosis mainly retained the characteristic histological features: it was represented by plates from the beams of collagen fibers between which were located fibrochondrocytes. By electron microscopic analysis of cells and cellular matrix of the annulus fibrosis, we have found dead cells with destruction of the plasma membrane, large lysosomes and decay products in the cytoplasm. Around these cells, violations of the location and structure of collagen fibers are detected. In 3 months after ovariectomy, significant bone tissue impairment adjacent to the intervertebral disc was detected. A characteristic feature was the formation of extended intertrabucular spaces similar to cyst-shaped cavities. Some of them had uneven contours with fragments of the bone in the lumen. The territory occupied by the nucleus has been expanded, cell density has been reduced, detritus foci have been discovered, which are accumulated in the regional areas. The pronounced changes are also found in the annulus fibrosis. On the sections of the plate collagen fibers were stratified. Different shape of the crack, aswell as uneven coloration were found. Some cells were diminished in size, had dense rounded nuclei that was not characteristic of cells of annulus fibrosis. Along with the change in the shape and structure of the nuclei of fibrochondrocytes, in some cells, the presence of edematous mitochondria with destroyed crystas was revealed, indicating a violation of energy cell metabolism. The pronounced changes are also observed in the intercellular substance of the annulus fibroses. On the basis of the morphometric analysis of the state of the intervertebral disk and the bone tissue adjacent to it, it was found that destructive changes are more pronounced in the bone tissue. Conclusion. The study found that the structure of the intervertebral disc and adjacent bone tissue negatively changes in early stages of osteoporosis in animals after ovariectomy with a greater manifestation in bone tissue.