What are the 7 circumventricular organs?
The seven circumventricular organs (shown as poppy-colored ovals) are the area postrema (AP), median eminence (ME), neurohypophysis (N), organum vasculosum of the lamina terminalis (OVLT), pineal (P), subcommissural organ (SCO), and subfornical organ (SFO).
Which are the circumventricular organs?
The circumventricular organs include the vascular organ (organum vasculosum), subfornical organ, neurohypophysis, median eminence, subcommissural organ, pineal gland and area postrema (Fig. 25.23). The vascular organ lies in the lamina terminalis between the optic chiasma and the anterior commissure.
What does Circumventricular mean?
The circumventricular organs (CVO) are structures that permit polypeptide hypothalamic hormones to leave the brain without disrupting the blood-brain barrier (BBB) and permit substances that do not cross the BBB to trigger changes in brain function.
What do circumventricular organs have in common?
Circumventricular organs (CVOs), small structures bordering the ventricular spaces in the midline of the brain, have common morphological and endocrine-like characteristics that distinguish them from the rest of the nervous system.
Is pineal gland a circumventricular organ?
The pineal gland, neurohypophysis and the median eminence lack the presence of neurons that are present in the rest of the circumventricular organs. Most of the circumventricular organs are lined by ependymal cells except the pineal and the neurohypophysis.
Which circumventricular organ is involved in osmoregulation?
The subfornical organ (SFO)
Like the OVLT, the SFO is a sensory CVO involved in osmoregulation (Bourque, 2008), but it has also been implicated in energy homeostasis (Medeiros et al. 2012; Hindmarch & Ferguson, 2016; Matsuda et al.
Is the pineal gland a circumventricular organ?
Examples of circumventricular organs include the area postrema, subfornical organ, posterior pituitary gland, and pineal gland.
Is the choroid plexus a circumventricular organ?
The choroid plexus, belongs to the circumventricular organs (CVOs) localized in the walls of the ventricles. Other CVOs, which similar to the choroid plexus lack an endothelial BBB, have not been considered as possible entry sites for immune cells into the CNS parenchyma or the CSF.
What is the Subfornical organ?
The subfornical organ (SFO) is a circumventricular organ recognized for its ability to sense and integrate hydromineral and hormonal circulating fluid balance signals, information which is transmitted to central autonomic nuclei to which SFO neurons project.
Is hypothalamus a circumventricular organ?
The pituitary neural lobe consists of axonal projections that directly extend from cell bodies in the hypothalamus through the infundibulum. Under neurohumoral control, it secretes oxytocin and vasopressin, thereby qualifying it as a circumventricular organ with both neural and secretory functions.
Where is Subfornical organ located?
third ventricle
The SFO is a forebrain midline structure located on the dorsal surface of the third ventricle below the ventral hippocampal commissure, and is primarily known for its well established roles in cardiovascular and neuroendocrine regulation (Ferguson & Bains, 1997; McKinley et al. 1998).
What does OVLT stand for?
Nonstandard Abbreviations and Acronyms
| ABP | arterial blood pressure |
|---|---|
| CNO | clozapine-N-oxide |
| OVLT | organum vasculosum of the lamina terminalis |
| SNA | sympathetic nerve activity |
What does the Subfornical organ do?
Where is OVLT located?
The organum vasculosum of the lamina terminalis (OVLT) resides along the rostral wall of the third ventricle, lacks a complete blood–brain barrier, and plays a pivotal role in body fluid homeostasis.
What is OVLT in medicine?
Organum vasculosum laminae terminalis (OVLT) is a brain site to produce interleukin-1 beta during fever. Brain Res.
What is the OVLT in the brain?
The OVLT is a midline structure on the anteroventral aspect of the third cerebral ventricle, ventral to the medial preoptic nucleus and dorsal to the optic chiasm. The densest efferent projections from the OVLT are monosynaptic and polysynaptic connections to the magnocellular neurons of the PVN and SON.
Is the OVLT in the hypothalamus?
7-5). Because it lies at the rostral and ventral tip of the third ventricle, the OVLT is surrounded by cell groups of the preoptic region of the hypothalamus.
Are OVLT and SFO in the hypothalamus?
The OVLT and SFO lie, respectively, at the ventral and dorsal boundaries of the third ventricle (seeFig. 7.5). Because it lies at the rostral and ventral tip of the third ventricle, the OVLT is surrounded by cell groups of the preoptic region of the hypothalamus.