Table of Contents
How do drugs pass blood brain barrier?
Most drugs cross the BBB by transmembrane diffusion [9]. This is a non-saturable mechanism that depends on the drug melding into the cell membrane. A low molecular weight and high degree of lipid solubility favor crossing by this mechanism.
What medications can pass through the blood brain barrier?
Small, lipid-soluble agents, such as antidepressants, cross the BBB via diffusion through endothelial cells. 3. Specialised transport proteins transport glucose, amino acids, and drugs like vinca alkaloids and cyclosporin, across the BBB.
How do drugs enter the brain through the BBB?
Drug Transport into Brain via Blood–Brain Barrier Carrier-Mediated Transporters. An alternative approach is to conjugate a drug, which normally does not cross the BBB, with a CMT substrate, for example, glucose, that does cross the BBB. This was attempted with oligopeptides, which were conjugated with glucose.
What is the function of the blood-brain barrier?
Introduction The blood-brain barrier (BBB) is a dynamic interface between the blood and the brain. It eliminates (toxic) substances from the endothelial compartment and supplies the brain with nutrients and other (endogenous) compounds.
Can small molecules cross the blood–cerebrospinal fluid barrier?
The BBB is anatomically and functionally distinct from the blood–cerebrospinal fluid barrier at the choroid plexus. Certain small molecule drugs may cross the BBB via lipid-mediated free diffusion, providing the drug has a molecular weight <400 Da and forms <8 hydrogen bonds.
How is morphine metabolized in the brain?
In addition to the liver, human brain homogenates have been shown to metabolize morphine at nanomolar concentrations to M3G and M6G; therefore, M6G can be formed directly in the CNS and seems to penetrate the BBB at a greater rate than the M6G produced in the liver (Yamada et al. 2003).