MOC : [[3 GARDEN/Notes/NEUROSCIENCES]] Source : [[Neurones et cellules gliales]] *** De [[3 GARDEN/Notes/Yoga Anatomy]] : **Glial cells** (figure 4.2) are divided into six groups: - **Astrocytes** are star-shaped cells that connect to each other and to neurons, blood vessels, and membranes in the brain and spinal cord. They play many roles in creating and modulating signaling networks in the CNS, including stimulating synapse creation, influencing (stimulating and inhibiting) synaptic activity, providing nourishment to neurons, and regulating blood flow in the brain. - **Oligodendrocytes** wrap around neurons in the brain and spinal cord (the CNS). This wrapping (called myelin) supports the neurons and facilitates the propagation of neuronal signals over long distances. - **Microglia** closely monitor the activity of the brain and spinal cord and provide immune functions such as removing dead and damaged cells and triggering inflammatory responses in the CNS when needed. They are closely related to white blood cells in the PNS. - **Ependymal** cells are cells in the CNS that line the inner surfaces of cavities in the brain and the central canal of the spinal cord to produce and regulate cerebrospinal fluid (and other functions). - **Neurolemmocytes** (Schwann cells) in the peripheral nervous system (PNS) wrap around the long parts (axons) of neurons (like the oligodendrocytes in the CNS). In some cases, these wrappings form myelin sheaths that help neuronal signals travel more quickly, efficiently, and predictably. In the PNS, neurolemmocytes also play a role in healing nerve damage. ([Location 1168](https://readwise.io/to_kindle?action=open&asin=B0998616FH&location=1168)) ## Caractéristiques des [[astrocyte]]s ? #flashcard Elles comblent l'espace entre les [[neurones]]. Elles représentent l'essentiel de l'espace dans lequel baignent les cellules. Elles pourraient être liées à la rétraction des [[Neurite]]. Elles régulent les transmissions de neurotransmetteurs, soit en facilitant un transfert, soit en empêchant qu'il se répande partout. Elles régulent aussi la présence d'éléments nuisibles comme l'ion potassium. <!--ID: 1612718878404--> ## [[Oligodendrocyte]] et [[cellule de Schwann]] composent quoi et ça sert à quoi ? #flashcard Ces deux cellules gliales conposent la gaîne qui protège les axones (composée de [[myéline]]) La gaîne permet de transporter l'info plus rapidement et elle est ouverte par endroits pour former des [[noeud de Ranvier]] <!--ID: 1612718878409--> ## Qu'est-ce qui compose la [[myéline]] ? [[Oligodendrocyte]] et [[cellule de Schwann]]