02-28-2008, 07:58 AM
Of the following, which is unlikely to be associated with drug distribution into and out of the central nervous system (CNS)?
A.
The blood-brain barrier, which involves drug movement through glial cell membranes as well as capillary membranes, is the main hindrance to drug distribution to the CNS
B.
Most drugs enter the CNS by simple diffusion at rates that are proportional to the lipid solubility of the nonionized form of the drug
C.
Receptor-mediated transport allows certain peptides to gain access to the brain
D.
Strongly ionized drugs freely enter the CNS through carrier-mediated transport systems
E.
Some drugs leave the CNS by passing from the cerebrospinal fluid into the dural blood sinuses through the arachnoid villi
A.
The blood-brain barrier, which involves drug movement through glial cell membranes as well as capillary membranes, is the main hindrance to drug distribution to the CNS
B.
Most drugs enter the CNS by simple diffusion at rates that are proportional to the lipid solubility of the nonionized form of the drug
C.
Receptor-mediated transport allows certain peptides to gain access to the brain
D.
Strongly ionized drugs freely enter the CNS through carrier-mediated transport systems
E.
Some drugs leave the CNS by passing from the cerebrospinal fluid into the dural blood sinuses through the arachnoid villi