Primary Component of Blood-Brain Barrier
The blood-brain barrier (BBB) is primarily formed by:
- Endothelial CNS cells — Correct Answer
- Cerebral cortex neurons
- Meningeal cells
- Astrocyte cell bodies
Explanation:
Correct Answer: Endothelial cells of CNS blood vessels
The Blood-Brain Barrier (BBB) is a physical/functional barrier that does not permit ionized and non-lipid-soluble drugs to pass into the CNS. It is mainly formed by the endothelial cells of the CNS blood vessels.
Key Features of BBB
- Brain capillaries do not contain fenestrations (holes).
- More tight junctions decrease diffusion through interstitial spaces.
- Glial cells ensheath brain capillaries providing a second set of cell membranes.
- Chemical/enzymatic barrier: MAO, cholinesterase prevent 5-HT, catecholamines, ACh from entering CNS.
Drugs and BBB Penetration
- Do NOT cross BBB: Penicillin, streptomycin, gentamicin.
- Can cross BBB: Chloramphenicol, lipid-soluble drugs.
📚 About this Topic — Veterinary Pharmacology and Toxicology
This multiple choice question is from Veterinary Pharmacology and Toxicology, Veterinary Science. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Veterinary Pharmacology and Toxicology to strengthen your preparation.
