Marcuzzo Simone, Dutra Márcio Ferreira, Stigger Felipe, do Nascimento Patrícia Severo, Ilha Jocemar, Kalil-Gaspar Pedro Ivo, Achaval Matilde
Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, RS, Brazil.
Brain Dev. 2010 Apr;32(4):323-31. doi: 10.1016/j.braindev.2009.04.016. Epub 2009 May 24.
Cerebral palsy (CP) is a group of movement and posture disorders attributed to insults in the developing brain. In rats, CP-like motor deficits can be induced by early hind-limb sensorimotor restriction (SR; from postnatal days P2 to P28), associated or otherwise with perinatal anoxia (PA; on P0 and P1). In this study, we address the question of whether PA, early SR or a combination of both produces alterations to sensorimotor development. Developmental milestones (surface righting, cliff aversion, stability on an inclined surface, proprioceptive placing, auditory startle, eye opening) were assessed daily from P3 to P14. Motor skills (horizontal ladder and beam walking) were evaluated weekly (from P31 to P52). In addition, on P52, the thickness of the somatosensory (S1) and cerebellar cortices, and corpus callosum were measured, and the neuronal and glial cell numbers in S1 were counted. SR (with or without PA) significantly delayed the stability on an inclined surface and hastened the appearance of the placing reflex and impaired motor skills. No significant differences were found in the thickness measurements between the groups. Quantitative histology of S1 showed that PA, either alone or associated with SR, increased the number of glial cells, while SR alone reduced neuronal cell numbers. Finally, the combination of PA and SR increased the size of neuronal somata. We conclude that SR impairs the achievement of developmental milestones and motor skills. Moreover, both SR and PA induce histological alterations in the S1 cortex, which may contribute to sensorimotor deficits.
脑性瘫痪（CP）是一组因发育中的大脑受到损伤而导致的运动和姿势障碍。在大鼠中，早期后肢感觉运动限制（SR；从出生后第2天到第28天）可诱发类似CP的运动缺陷，这与围产期缺氧（PA；在出生第0天和第1天）有关或无关。在本研究中，我们探讨了PA、早期SR或两者结合是否会导致感觉运动发育的改变。从出生后第3天到第14天，每天评估发育里程碑（表面翻正、悬崖回避、在倾斜表面上的稳定性、本体感觉放置、听觉惊吓、睁眼）。每周（从出生后第31天到第52天）评估运动技能（水平梯子行走和横梁行走）。此外，在出生后第52天，测量体感皮层（S1）、小脑皮层和胼胝体的厚度，并计算S1中的神经元和神经胶质细胞数量。SR（无论有无PA）显著延迟了在倾斜表面上的稳定性，加速了放置反射的出现，并损害了运动技能。各组之间在厚度测量上未发现显著差异。S1的定量组织学显示，PA单独或与SR联合使用时，会增加神经胶质细胞数量，而单独的SR会减少神经元细胞数量。最后，PA和SR的组合增加了神经元胞体的大小。我们得出结论，SR会损害发育里程碑的达成和运动技能。此外，SR和PA都会在S1皮层引起组织学改变，这可能导致感觉运动缺陷。
