Circumventricular organs (CVOs) are structures in the brain characterized by their extensive and highly permeable capillaries, unlike those in the rest of the brain where there exists a blood–brain barrier (BBB) at the capillary level. Although the term "circumventricular organs" was originally proposed in 1958 by Austrian anatomist Helmut O. Hofer concerning structures around the brain ventricular system, the penetration of blood-borne dyes into small specific CVO regions was discovered in the early 20th century. The permeable CVOs enabling rapid neurohumoral exchange include the subfornical organ (SFO), the area postrema (AP), the vascular organ of lamina terminalis (VOLT), the median eminence, the pituitary neural lobe, and the pineal gland.
Thrombospondin 1, abbreviated as THBS1, is a protein that in humans is encoded by the THBS1 gene.
The subcommissural organ (SCO) is one of the circumventricular organs of the brain. It is a small glandular structure that is located in the posterior region of the third ventricle, near the entrance of the cerebral aqueduct.
A disintegrin and metalloproteinase with thrombospondin motifs 4 is an enzyme that in humans is encoded by the ADAMTS4 gene.
Cadherin EGF LAG seven-pass G-type receptor 3 is a protein that in humans is encoded by the CELSR3 gene.
A disintegrin and metalloproteinase with thrombospondin motifs 1 is an enzyme that in humans is encoded by the ADAMTS1 gene.
Neuroligin-3 is a protein that in humans is encoded by the NLGN3 gene.
Spondin-1 is a protein that in humans is encoded by the SPON1 gene. It is secreted by cells of the floor plate and may be involved in axon guidance The protein contains 807 amino acids and is structurally composed of six thrombospondin domains, one reelin domain, and one spondin domain.
Myelin transcription factor 1 is a protein that in humans is encoded by the MYT1 gene.
A disintegrin and metalloproteinase with thrombospondin motifs 8 is an enzyme that in humans is encoded by the ADAMTS8 gene.
Leucine-rich repeat neuronal protein 1 is a protein that in humans is encoded by the LRRN1 gene.
ADAMTS-like protein 1 is a protein that in humans is encoded by the ADAMTSL1 gene.
Plexin-D1 is a protein that in humans is encoded by the PLXND1 gene.
R-spondin-1 is a secreted protein that in humans is encoded by the Rspo1 gene, found on chromosome 1. In humans, it interacts with WNT4 in the process of female sex development. Loss of function can cause female to male sex reversal. Furthermore, it promotes canonical WNT/β catenin signaling.
SLIT and NTRK-like protein 5 is a protein that in humans is encoded by the SLITRK5 gene.
A disintegrin and metalloproteinase with thrombospondin motifs 12 is an enzyme that in humans is encoded by the ADAMTS12 gene.
R-spondin-3 is a protein that in humans is encoded by the RSPO3 gene.
FCH and double SH3 domains protein 1 is a protein that in humans is encoded by the FCHSD1 gene.
Von Willebrand factor, type C is a protein domain is found in various blood plasma proteins: complement factors B, C2, CR3 and CR4; the integrins (I-domains); collagen types VI, VII, XII and XIV; and other extracellular proteins.
Reissner's fiber(named after Ernst Reissner) is a fibrous aggregation of secreted molecules extending from the subcommissural organ (SCO) through the ventricular system and central canal to the terminal ventricle, a small ventricle-like structure near the end of the spinal cord. In vertebrates, Reissner's fiber is formed by secretions of SCO-spondin from the subcommissural organ into the ventricular cerebrospinal fluid. Reissner's fiber is highly conserved, and present in the central canal of all chordates. In cephalochordates, Reissner's fiber is produced by the ventral infundibular organ, as opposed to the dorsal SCO.
