Isaacs K R, Anderson B J, Alcantara A A, Black J E, Greenough W T
Beckman Institute, University of Illinois, Urbana.
J Cereb Blood Flow Metab. 1992 Jan;12(1):110-9. doi: 10.1038/jcbfm.1992.14.
This study compared the morphology of cerebellar cortex in adult female rats exposed for 1 month to repetitive exercise, motor learning, or an inactive condition. In the exercise conditions, rats that were run on a treadmill or housed with access to a running wheel had a shorter diffusion distance from blood vessels in the molecular layer of the paramedian lobule when compared to rats housed individually or rats that participated in a motor skill learning task. Rats taught complex motor skills substantially increased the volume of the molecular layer per Purkinje neuron and increased blood vessel number sufficiently to maintain the diffusion distance. These results dissociate angiogenesis associated with increased neuropil volume (as seen in the motor learning group) from angiogenesis associated with increased metabolic demands (as seen in the exercise groups). While the volume fraction of mitochondria did not differ among groups, the mitochondrial volume fraction per Purkinje cell was significantly increased in the motor skill rats. This appears to parallel the previously reported increase in synapses and associated neuropil volume change.
本研究比较了成年雌性大鼠在重复运动、运动学习或非活动状态下暴露1个月后的小脑皮质形态。在运动条件下，与单独饲养的大鼠或参与运动技能学习任务的大鼠相比，在跑步机上跑步或有跑轮可供使用的大鼠，其旁正中小叶分子层血管的扩散距离更短。学习复杂运动技能的大鼠显著增加了每个浦肯野神经元的分子层体积，并充分增加了血管数量以维持扩散距离。这些结果将与神经毡体积增加相关的血管生成（如运动学习组所示）与与代谢需求增加相关的血管生成（如运动组所示）区分开来。虽然各组之间线粒体的体积分数没有差异，但运动技能大鼠每个浦肯野细胞的线粒体体积分数显著增加。这似乎与先前报道的突触增加和相关神经毡体积变化相平行。
