Efflux transporters Flashcards
What is the mechanism of efflux transporters?
Primary active transport - use ATP as an energy source
ABC transporters are efflux transporters. True or false?
True
Efflux transporters form a ____ in the membrane
pore
Efflux transporters recognise all drugs so any that come in contact are pumped out of the cell. True or false?
False - don’t recognise all drugs
Efflux transporters protect the body from exposure to dietary and environmental xenobiotics, True or false?
True
Efflux transporters don’t affect ADME. True or false?
False
Can efflux transporters distinguish between good and bad drugs?
No
Xenobiotics are excreted and metabolites are metabolised. True or false?
False - xenobiotics are metabolised and metabolites are excreted
Drugs are excreted from the body via which two organs?
Liver
Kidneys
P-gp is expressed in the ______ membrane of the intestinal epithelial cells
apical
P-gp doesn’t reduce the absorption of drugs. True or false?
False
How does p-gp work in the liver?
Drug diffuses into hepatocyte, it is recognised by p-gp which pumps it into bile and then drug moves to intestine
How does p-gp work in the kidneys?
Drug circulates in blood then diffuses into cell, it is then pumped into the tabular fluid by p-gp and out into the urine
To treat CNS disorders, drugs must cross the ____
BBB
In the brain, the drug needs to leave the capillary to hit the target cell. What is the problem that the drug faces?
P-gp and BCRP are in the membrane - they pump the drug in circulation, reducing the amount going in CNS
