摘要
The glia are the cells in the central nervous system(CNS)that originally were considered to only provide support,protection,and nutrition for neurons.The glia outnumber the neurons in the brain and spinal cord,the ratio of these two types of cells varies across species and tissues.The word"glia"comes from"glue",describing the cells that surround neurons and gathering them together like glue.However,in the past decades,studies gradually revealed the key roles of the glia and their heterogeneity in term of categorie and function.
