Differences between blood-brain barrier and blood- testis barrier.

BLOOD-BRAIN BARRIER:

1. The blood-brain barrier is a highly selectively semipermeable membrane barrier that separates the circulating blood from the brain and extracellular fluid in CNS.
2. It is formed by brain endothelial cells and allows passage of water, some gases and lipid soluble molecules.
3. This barrier protects the brain from most pathogens protecting it from blood borne infections. It also prevents toxins like neurotoxins and botulinum toxin from reaching CNS.
4. Examples of pathogens that transverse the BBB- Toxoplasma gondii, Borrelia (Lyme disease), Treponema pallidum (syphilis).

BLOOD-TESTIS BARRIER:

1. The blood-testis barrier is a physical barrier between the blood vessels and the seminiferous tubules of the animal testis.
2. It is found between adjacent Sertoli cells within the Seminiferous tubules. It is not actually a blood organ barrier and is also called as "Sertoli cell barrier"(SCB).
3. The SCB controls the environment in which germ cells develop. The barrier also prevents passage of cytotoxic agents into the seminiferous tubules.
4. The Blood-Testis barrier can be damaged by trauma to testis, by surgery or due to vasectomy.