Mikheeva I B, Shtanchaev R Sh, Pen'kova N A, Pavlik L L
Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
Bull Exp Biol Med. 2018 Aug;165(4):457-460. doi: 10.1007/s10517-018-4193-8. Epub 2018 Aug 18.
Ultrastructure of the neuropil of the brain oculomotor nuclei was studied in mice after 30-day exposure to microgravity on Bion-M1 biosatellite and after 13-h exposure to Earth gravity. The number of axo-dendritic synapses in the neuropil of the oculomotor nucleus significantly decreased after the flight. Degenerated axon terminals containing conglomerates of presynaptic vesicles appeared. The number of synapses with high functional activity increased and the length of active zones of the axo-dendritic synapses significantly increased. The observed ultrastructural changes of the neuropil of the oculomotor nuclei of mice exposed to microgravity reflect the development of long-term deafferentation of the analyzed brain structures. These changes in the neuropil ultrastructure can determine the disturbances in the oculomotor system, e.g. development of atypical nystagmus under conditions of microgravity.
在“生物-M1”生物卫星上暴露于微重力环境30天以及在地球重力环境下暴露13小时后，对小鼠动眼神经核神经毡的超微结构进行了研究。飞行后，动眼神经核神经毡中轴突-树突突触的数量显著减少。出现了含有突触前囊泡聚集体的退化轴突终末。具有高功能活性的突触数量增加，轴突-树突突触活性区的长度显著增加。暴露于微重力环境下的小鼠动眼神经核神经毡观察到的超微结构变化反映了所分析脑结构长期传入缺失的发展。神经毡超微结构的这些变化可确定动眼系统的紊乱，例如在微重力条件下非典型眼球震颤的发展。
