Ependymal cells are specialized glial cells that line the ventricles of the brain and the central canal of the spinal cord. They play a crucial role in the production and circulation of cerebrospinal fluid (CSF), which cushions the brain and spinal cord, providing protection and maintaining homeostasis. These cells have cilia on their surface that help move the CSF throughout the central nervous system. Ependymal cells also contribute to the blood-CSF barrier, regulating the exchange of substances between the blood and the CSF, which is essential for maintaining the proper environment for neurons and other cells in the nervous system.