英国研究人员最新研究发现,星形胶质细胞在调节呼吸方面发挥着关键作用。该发现表明大脑组织功能与呼吸衰竭有密切关系,而星形胶质细胞或可成为防止呼吸衰竭的治疗标靶。该研究发表将发表《科学》(Science)杂志上。
神经胶质细胞是哺乳动物神经组织中除神经元以外的另一大类细胞,其数量为神经元的10倍。直到最近,科学家都认为神经胶质细胞只是为神经元提供结构和营养支持,而星形胶质细胞作为神经胶质细胞中最大的一种,则只是在神经元间起到联结纽带的作用。
英国布里斯托大学和伦敦大学学院的研究人员通过先进的基因转移技术,对小鼠大脑中星形胶质细胞的活动进行观察后发现,该种细胞的化学敏感度极高,能够感知血液中二氧化碳水平的变化,当二氧化碳含量过高时,它们会释放化学信号三磷酸腺苷(ATP),刺激大脑神经中枢调整呼吸强度,以移除血液中过多的二氧化碳。
研究人员表示,该发现表明,星形胶质细胞可根据不断变化的新陈代谢和活动需要来调节呼吸强度,它在呼吸调节方面居于中心地位。而神经胶质细胞功能障碍很可能与婴儿猝死综合征或先天中枢性换气不足症有关。如果这个假设正确,星形胶质细胞则可作为防止呼吸衰竭的潜在治疗标靶。(生物谷Bioon.com)
生物谷推荐原文出处:
Science DOI: 10.1126/science.1190721
Astrocytes Control Breathing Through pH-Dependent Release of ATP
Alexander V. Gourine,1,* Vitaliy Kasymov,1 Nephtali Marina,1 Feige Tang,2 Melina F. Figueiredo,2 Samantha Lane,2 Anja G. Teschemacher,2 K. Michael Spyer,1 Karl Deisseroth,3 Sergey Kasparov2,*
Astrocytes provide structural and metabolic support for neuronal networks, but direct evidence demonstrating their active role in complex behaviors is limited. Central respiratory chemosensitivity is an essential mechanism which, via regulation of breathing, maintains constant levels of blood and brain PCO2/pH. We found that astrocytes of the brainstem chemoreceptor areas are highly chemosensitive. They responded to physiological decreases in pH with vigorous elevations in intracellular Ca2+ and release of ATP. ATP propagated astrocytic Ca2+ excitation, activated chemoreceptor neurons, and induced adaptive increases in breathing. Mimicking pH-evoked Ca2+ responses by optogenetic stimulation of astrocytes expressing channelrhodopsin-2 activated chemoreceptor neurons via ATP-dependent mechanism and triggered robust respiratory responses in vivo. This demonstrates a potentially crucial role for brain glial cells in mediating a fundamental physiological reflex.
1 Neuroscience, Physiology, and Pharmacology, University College London, London WC1E 6BT.
2 Department of Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, United Kingdom.
3 Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.