Effects of oophorectomy on the lumbar spine of Wistar rats submitted to vibratory platform treatment

Abstract

Introduction: This study evaluated the effect of the vibratory platform on the lumbar spine morphology of Wistar rats submitted to hormonal deprivation by oophorectomy. Material and method: Twenty rats were divided into four groups: Pseudo-oophorectomy (GP), Pseudo-oophorectomy Treated (GPT), Oophorectomy (GO), Oophorectomy Treated (GOT). After 60 days of postoperative, the treated groups started exercises on a vibratory platform in the frequency parameters of 60 Hz, alternating vibration with amplitude of 2 mm, acceleration of 57.6 m/s² and time of 10 minutes, three times in the during the four week period. Following the euthanasia of the animals, the lumbar spine was dissected and processed for analysis of the anterior and posterior longitudinal ligaments, intervertebral disc height (IVD), nucleus pulposus (NP) height, radiographic density of the lumbar vertebrae and IVD morphology. Results: The results showed a decrease in the height of the NP associated to the GO and morphological alterations such as lamellar disorganization and presence of rifts in the fibrous ring, alterations of the structural limits and decrease of the NP cavity; while the other groups presented organized lamellae, peripheral and nuclear region well delimited and wide cavity of the nucleus. Conclusion: In this way, it can be concluded that the oophorectomy protocol promoted a decrease in the height of the NP of the IVD and that the exercise in the vibratory platform did not generate lesions in the analyzed tissues, as well as preserved the structural organization of the IVD and the height of the NP of oophorectomized rats.