The term "ependymas" refers to the lining of the ventricles of the brain and the central canal of the spinal cord. Its pronunciation is ɛpənˈdɪməs, with the stress on the second syllable. The first syllable -ep- is pronounced as "ep" in "episode", while the second syllable -en- is pronounced as "en" in "end". The third syllable -dy- is pronounced as "dy" in "dye", and the fourth syllable -mas- is pronounced as "mas" in "mass". Getting the spelling right can be challenging, but phonetic transcription can help break down the sounds and make it easier to remember.
Ependymas refers to a thin layer of specialized cells that lines the ventricles of the brain and the central canal of the spinal cord. It is an essential component of the central nervous system (CNS) and plays a crucial role in the regulation of cerebrospinal fluid (CSF) production and flow.
The ependymal cells are unique in their morphology and function. They have a cuboidal or columnar shape and are arranged in a single layer. These cells possess cilia or microvilli on their surface, which aid in the movement of CSF. They also contain tight junctions that form a barrier known as the blood-brain barrier, regulating the exchange of substances between the bloodstream and the CNS.
Furthermore, ependymal cells have numerous specialized functions. They help produce CSF, a clear fluid that acts as a cushion for the brain and spinal cord, provides nutrients, and removes waste products. Ependymal cells also serve as stem cells, capable of differentiating into other cell types within the CNS, including astrocytes and neurons.
Dysfunction or abnormalities in the ependymas can lead to various neurological disorders, such as hydrocephalus, where there is an accumulation of CSF within the brain. Understanding the structure and function of ependymas is essential for understanding brain development, fluid dynamics, and maintaining overall brain health.
The word "ependyma" is derived from the Greek ἐπένδυμα (ependyma), which means a covering or a garment. In medical terminology, ependyma refers to a thin membrane lining the ventricles of the brain and the central canal of the spinal cord. The term was first used in the 17th century to describe this specific anatomical structure.