tanycytesa

The term tanycytesa does not correspond to a widely recognized cell type in current neuroscience literature. It is likely a misspelling, variant, or pluralization of tanycyte or tanycytes. This article uses tanycyte as the standard term and summarizes what is known about tanycytes and their roles in the hypothalamus.

Tanycytes are specialized glial cells of the brain that form a single-cell lining along the ventricular wall of the third ventricle, particularly in the mediobasal hypothalamus. They have slender apical processes that contact cerebrospinal fluid and long basal processes that extend toward hypothalamic nuclei and nearby capillaries, effectively bridging CSF and hypothalamic tissue.

Researchers classically describe tanycytes as two broad subtypes based on location: alpha (α) tanycytes lining the rostral third ventricular wall and beta (β) tanycytes located ventromedially near the median eminence. These subtypes differ in morphology and reach, with β-tanycytes often extending toward the portal capillaries of the median eminence.

Functions attributed to tanycytes include regulation of the hypothalamic neuroendocrine axis, transport and metabolism of metabolic signals such as leptin and insulin, and modulation of neuronal activity in energy balance circuits. They may also participate in neurogenic processes and contribute to the blood-CSF barrier properties of the hypothalamus.

Developmentally, tanycytes arise from neural progenitor cells during brain development and are found across many mammals, with some species-specific differences in distribution and abundance. Their study spans neuroendocrinology, metabolism, and brain barrier biology.