Transporters Flashcards
What dictates how well a compound crosses a membrane
Lipid solubility
Degree of ionisation
pH differences between compartments
2 types of transporter
Facilitative
Secondary active (co-substrate)
- neither use ATP
Location of OATPs
Sinusoidal membrane of liver
OATPs are encoded by ..
SLCO1-6
Substrates for OATPs
Anions with high MW
Statins, rifampicin, benzylpenicillin
OAT main role
Renal excretion
Location of OATs
1-3 on basolateral membrane of kidney
4 on apical membrane of kidney
Substrates for OATs
Sulphate or glucuronide conjugates
OCT locations
OCT1 - sinusoidal face of liver
OCT2 - basolateral membrane of kidney
OCT substrate
Metformin, cisplatin
PEPT locations
PEPT1 - intestine and kidney
PEPT2 - kidney
PEPT substrates
Penicillins, ACE inhibitors
(Proton dependent)
MATE locations
MATE1 - liver and kidney
MATE2 - kidney only
MATE function
Proton dependent transport of cations for biliary and renal excretion
Membrane involved in intestine transport
Enter enterocytes through brush boarder membrane then enter hepatic portal vein through basolateral membrane
Membrane involved in liver transport
Across sinusoidal membrane to enter
Out across canalicular membrane to bile or sinusoidal membrane to blood
Explain diclofenac transport
CYP2C9 and UGT metabolism makes acyl glucuronide
OAT2 and 4 renal excretion
2 common polymorphisms
OATP1 - toxic levels of statins in muscle
OCT2 - nephrotoxicity from cisplatin