Download Careers360 App
Choroid plexus: Definition, Function, Structures, Diagram, Facts, FAQs

Choroid plexus: Definition, Function, Structures, Diagram, Facts, FAQs

Edited By Irshad Anwar | Updated on Jul 02, 2025 06:49 PM IST

What Is Choroid Plexus?

The choroid plexus is a collection of cells located within the ventricles of the brain, especially inside the lateral, third, and fourth ventricles. It comprises ependymal cells, blood vessels, and connective tissue and forms the CSF. The choroid plexus filters blood for the production of CSF, which later goes into the brain and spinal cord, cushioning, nourishing, and clearing waste products. It forms a part of the maintenance of the internal environment of the brain and helps in the sustenance of neural health for overall correct functionality of the central nervous system.

This Story also Contains
  1. What Is Choroid Plexus?
  2. Anatomy Of The Choroid Plexus
  3. Functions Of The Choroid Plexus
  4. Recommended video for "Choroid Plexus"
Choroid plexus: Definition, Function, Structures, Diagram, Facts, FAQs
Choroid plexus: Definition, Function, Structures, Diagram, Facts, FAQs

Anatomy Of The Choroid Plexus

The choroid plexus is a structure inside the ventricles of the brain that accounts for the largest proportion of cerebrospinal fluid production. It can be found in all parts of the ventricles inside the brain, namely the lateral, third, and fourth ventricles.

Location and Structure Of Choroid Plexus

  • The choroid plexus lies in all four ventricles of the brain, namely, two lateral ventricles, the third ventricle, and the fourth ventricle.

  • The location extends from the lateral ventricles through the interventricular foramina into the third ventricle, then goes on through the cerebral aqueduct into the fourth ventricle.

  • The choroid plexus is composed of an epithelium layer, connective tissue, and a rich network of blood vessels.

  • The epithelium is lined by cuboidal choroidal epithelial cells that secrete CSF.

  • The choroidal epithelial cells are underlaid by thin stroma connective tissue under the epithelium to which blood vessels that supply the plexus are anchored.

  • These blood vessels are fenestrated and allow the filtration of blood plasma into the ventricles to form CSF.

1725614584931

Histology

  • The choroid plexus is very defined and complicated when viewed microscopically.

  • These epithelial cells, otherwise named ependymal cells, appear cuboidal to columnar and cover the connective tissue core underlying them continuously.

  • The major cells of the choroid plexus include epithelial cells, also called choroidal epithelial cells or ependymal cells.

  • These cells have microvilli and cilia on the apical surface that will aid in the movement and secretion of CSF.

  • Also, under the stromal connective tissue, there are several kinds of support cells and blood vessels to help in the exchange of materials for CSF production.

Functions Of The Choroid Plexus

The choroid plexus is the part of the brain that is responsible for the significant production of CSF and the maintenance of the blood-CSF barrier.

Cerebrospinal Fluid (CSF) Production

  • It is produced by the choroid plexus through the process involving filtration of blood plasma.

  • This makes the blood vessels within the choroid plexus fenestrated, and as such, plasma passes through them into the stroma.

  • At this point, the choroidal epithelial cells secrete this filtrate into the ventricles as CSF, enriched with essential ions, nutrients, and other substances.

  • It regulates the volume and composition of the CSF.

  • It maintains the volume of the CSF with the proper balance of the electrolytes, glucose, and other essential molecules.

  • With this, it controls the intracranial pressure and gives the best environment for the proper functioning of the neurons.

NEET Highest Scoring Chapters & Topics
Know Most Scoring Concepts in NEET 2024 Based on Previous Year Analysis.
Know More

Blood-CSF Barrier

  • The blood-CSF barrier derives from tight junctions between the choroidal epithelial cells.

  • These junctions hamper free diffusion into the CSF from the blood for large molecules and pathogens but allow, in a selective manner, the majority of essential nutrients and ions.

Importance In Protecting The Brain

  • Blood-CSF prevents most of the noxious chemicals and pathogenic agents from the blood into the CSF and eventually into the CNS.

  • It becomes rather important to maintain such an optimal environment to protect the safe and stable operation of the brain.

Recommended video for "Choroid Plexus"


Frequently Asked Questions (FAQs)

1. What is the function of the choroid plexus?

Probably, the most vital role played by the choroid plexus is that it fabricates and controls cerebrospinal fluid. This liquid serves to cushion the brain and the spinal cord, nourish them, wash out wastes, and also maintain a constant environment around the central nervous system. This organ also regulates the blood-CSF barrier to protect the brain from any toxin or pathogen that may harm the organ.

2. Where is the choroid plexus located?

It is found in the ventricles of the brain. The choroid plexus is situated within the lateral ventricles, third ventricle, and fourth ventricle. Its extensions from the lateral ventricles move into the third ventricle through interventricular foramina and further continue in the cerebral aqueduct into the fourth ventricle.

3. What disorders are associated with the choroid plexus?

The disorders related to it are hydrocephalus, owing to the accumulation of CSF that results in increased pressure in the brain and the Choroid plexus Papillomas/ Carcinomas are the tumours obstructing the flow or formation of CSF. Other conditions include infections and inflammations of the choroid plexus, thus affecting CSF formation and composition.

4. How is choroid plexus function assessed?

Imaging techniques such as magnetic resonance imaging and computed tomography show the anatomical structure of the choroid plexus and define any abnormality. The analysis of the CSF samples may explain the composition and probably the dysfunctions of the choroid plexus. Techniques like positron emission tomography are used to study the long-term metabolic activity in the choroid plexus.

5. Can choroid plexus cells be used in regenerative medicine?

Yes, a few potential uses of choroid plexus cells are in the pipeline in regenerative medicine that is currently under research for neurological disorders and brain injuries. It is based on evidence that these cells produce CSF and house the homeostatic capacity to maintain the microenvironment of the brain. Long-term research is underway to make their regenerative properties available for use as a therapy.

6. Where is the choroid plexus located in the brain?
The choroid plexus is found in all four ventricles of the brain: the two lateral ventricles, the third ventricle, and the fourth ventricle. Each ventricle contains its own choroid plexus structure.
7. What are the main structural components of the choroid plexus?
The main structural components of the choroid plexus include:
8. How does the structure of choroid plexus capillaries differ from typical capillaries?
Choroid plexus capillaries are fenestrated, meaning they have small pores or "windows" in their walls. This structure allows for easier passage of water and small molecules from the blood into the choroid plexus tissue, facilitating CSF production.
9. What is the role of ependymal cells in the choroid plexus?
Ependymal cells in the choroid plexus are specialized epithelial cells that play a crucial role in CSF production. They actively transport ions and other molecules to create the unique composition of CSF and form the blood-CSF barrier through tight junctions.
10. What is the difference between the blood-brain barrier and the blood-CSF barrier?
While both barriers protect the central nervous system, they differ in location and structure:
11. What is the primary function of the choroid plexus?
The primary function of the choroid plexus is to produce cerebrospinal fluid (CSF), which surrounds and protects the brain and spinal cord. CSF also helps deliver nutrients to the brain and remove waste products.
12. How does the choroid plexus produce cerebrospinal fluid?
The choroid plexus produces CSF through a process of filtration and secretion. Blood plasma is filtered through the capillaries of the choroid plexus, and then specialized ependymal cells actively secrete additional components to form CSF.
13. How much cerebrospinal fluid does the choroid plexus produce daily?
The choroid plexus produces approximately 400-600 mL of cerebrospinal fluid per day in adults. This amount is enough to replace the entire volume of CSF in the central nervous system 3-4 times daily.
14. How does the choroid plexus contribute to brain homeostasis?
The choroid plexus helps maintain brain homeostasis by regulating the composition of cerebrospinal fluid, removing waste products, and controlling the entry of substances into the central nervous system. This helps create a stable environment for proper brain function.
15. What is the blood-CSF barrier, and how does it relate to the choroid plexus?
The blood-CSF barrier is a selective barrier formed by the tight junctions between the ependymal cells of the choroid plexus. It regulates the passage of substances between the blood and the cerebrospinal fluid, protecting the brain from potentially harmful substances.
16. What is the choroid plexus?
The choroid plexus is a specialized tissue located in the ventricles of the brain. It consists of a network of blood vessels covered by ependymal cells, which are responsible for producing cerebrospinal fluid (CSF).
17. What are choroid plexus papillomas, and how do they affect CSF production?
Choroid plexus papillomas are rare, usually benign tumors that arise from choroid plexus tissue. They can affect CSF production by:
18. What are the main differences between choroid plexus ependymal cells and other ependymal cells in the brain?
Choroid plexus ependymal cells differ from other ependymal cells in:
19. How does the choroid plexus change during fetal development?
During fetal development, the choroid plexus:
20. How does the choroid plexus differ among different species?
While the basic structure and function of the choroid plexus are similar across vertebrates, there are some differences:
21. What is the composition of cerebrospinal fluid?
Cerebrospinal fluid is primarily composed of water (99%), along with small amounts of glucose, proteins, electrolytes (such as sodium and potassium), and white blood cells. Its composition is carefully regulated by the choroid plexus.
22. What are some disorders associated with choroid plexus dysfunction?
Disorders associated with choroid plexus dysfunction include:
23. How does the choroid plexus respond to inflammation or infection?
During inflammation or infection, the choroid plexus can:
24. What is the evolutionary significance of the choroid plexus?
The evolutionary significance of the choroid plexus includes:
25. How does the choroid plexus contribute to the removal of waste products from the brain?
The choroid plexus helps remove waste products from the brain by:
26. What is the relationship between the choroid plexus and the glymphatic system?
The choroid plexus and the glymphatic system work together to maintain brain health. While the choroid plexus produces CSF, the glymphatic system uses the flow of CSF to help clear waste products from the brain, particularly during sleep.
27. How does aging affect the choroid plexus?
Aging can lead to several changes in the choroid plexus, including:
28. How does the choroid plexus contribute to brain development?
The choroid plexus plays a crucial role in brain development by:
29. What imaging techniques are used to visualize the choroid plexus?
The choroid plexus can be visualized using various imaging techniques, including:
30. How does the choroid plexus regulate ion concentrations in the CSF?
The choroid plexus regulates ion concentrations in the CSF through:
31. What is the role of aquaporins in the choroid plexus?
Aquaporins, particularly aquaporin-1 (AQP1), play a crucial role in the choroid plexus by:
32. How does the choroid plexus contribute to neuroprotection?
The choroid plexus contributes to neuroprotection by:
33. What is the relationship between the choroid plexus and cerebrospinal fluid pressure?
The choroid plexus influences cerebrospinal fluid pressure by:
34. How does the choroid plexus contribute to drug delivery to the brain?
The choroid plexus can influence drug delivery to the brain by:
35. What is the role of the choroid plexus in neurodegenerative diseases?
In neurodegenerative diseases, the choroid plexus may:
36. How does the circadian rhythm affect choroid plexus function?
The choroid plexus exhibits circadian rhythms in:
37. How does the choroid plexus interact with the rest of the brain?
The choroid plexus interacts with the rest of the brain by:
38. How does the choroid plexus contribute to the brain's immune system?
The choroid plexus contributes to the brain's immune system by:
39. What is the role of the choroid plexus in maintaining the brain's extracellular fluid balance?
The choroid plexus helps maintain brain extracellular fluid balance by:
40. How does the choroid plexus respond to traumatic brain injury?
Following traumatic brain injury, the choroid plexus may:
41. What is the relationship between the choroid plexus and cerebral blood flow?
The choroid plexus and cerebral blood flow are related in several ways:
42. How does the choroid plexus contribute to the regulation of brain temperature?
The choroid plexus helps regulate brain temperature by:
43. What are the main transport proteins expressed in the choroid plexus, and what are their functions?
Key transport proteins in the choroid plexus include:
44. What is the role of the choroid plexus in metal ion homeostasis in the brain?
The choroid plexus helps maintain metal ion homeostasis in the brain by:
45. How does the choroid plexus contribute to the regulation of sleep and wakefulness?
The choroid plexus influences sleep and wakefulness by:

Articles

Back to top