tanycyte

A tanycyte is a specialized type of glial cell found in the ependymal lining of the third ventricle of the brain. These cells are elongated and have a characteristic radial morphology, with their cell bodies located in the ventricular ependyma and their processes extending into the hypothalamic parenchyma. Tanycytes are distinct from other ependymal cells due to their unique structural and functional properties.

Functionally, tanycytes are believed to play a crucial role in mediating the communication between the cerebrospinal fluid (CSF) and the brain's neuroendocrine system, particularly the hypothalamus. Their processes often surround blood vessels, forming a barrier that regulates the passage of substances between the CSF and the hypothalamic tissue. This proximity to both the CSF and vascular supply suggests a role in sensing and transporting molecules, such as hormones and nutrients, from the CSF to the hypothalamus, and potentially vice versa.

Research has implicated tanycytes in various physiological processes, including energy homeostasis, reproduction, and glucose metabolism. They are thought to be involved in sensing circulating hormones and nutrient levels, and relaying this information to hypothalamic neurons that control feeding behavior and metabolic regulation. Their precise mechanisms of action and the full extent of their involvement in these processes are areas of ongoing investigation.