Human Anatomy - Kotsan I. Ya. 2009

Brain
Cerebrospinal fluid

CEREBROSPINAL FLUID (liquor cerebrospinalis), which fills the subarachnoid spaces of the Brain AND SPINAL cord as well as the brain ventricles, differs sharply from other Body Fluids. It is similar in composition to the endolymph and perilymph of the Inner ear and the aqueous humor of the eye. Normal cerebrospinal fluid is transparent and contains a small amount of protein along with occasional lymphocytes. In cases of injury and disease, its composition changes. The examination of cerebrospinal fluid is of great practical importance in medicine. It performs trophic and protective Functions and participates in METABOLISM. The secretion of cerebrospinal fluid occurs through the choroid plexuses of the ventricles, whose epithelial lining has the character of Glandular Epithelium. The apparatus producing cerebrospinal fluid has The ability to pass certain substances into the fluid while retaining others (the Blood-brain barrier), which is crucial for protecting the brain from harmful influences. Thus, due to its specific characteristics, cerebrospinal fluid serves not only as a mechanical protective cushion for the brain and the Blood Vessels located at its base, but also as a specialized internal environment essential for the proper functioning of the Central Nervous system.