Pharmacology: Glucocorticoids Flashcards
what class of drugs are glucocorticoids
steroids
what receptors do glucocorticoids bind to and where in the cell are they
Glucocorticoid receptors(GR) in the cytoplasm
describe glucocorticoids movement in the cell
can cross cell membrane as they are lipophilic
describe what happens when glucocorticoids bind to GR
migrate from cytoplasm to nucleus and bind to DNA, can either result in transactivation or transrepression
(regulates transcription)
what is the section of DNA that glucocorticoid(bound to GR) binds to
glucocorticoid recognition/response element(GRE)
what types of DNA sequence favour and suppress GR dimer formation
+GRE sequence favours dimer formation
nGRE sequence suppresses dimer formation
what affect does a steroid bound GR dimer have on transcription
gene expression induced(transactivation)
what affect does a steroid bound GR monomer have on transcription
gene expression suppressed(transrepression)
what types of GRE sequence do monomer and dimer steroid bound GRs bind to
monomer = nGRE(transrepression) dimer = +GRE(transactivation)
what type of mutation are GRE sequences in DNA, and why is this clinically relevant
polymorphism, means different people have different tolerances/susceptibility to steroids
what secondary receptor can glucocorticoids also bind to and activate
mineralocorticoid receptors
what clinical side effects of glucocorticoids can be caused by binding to mineralocorticoid receptors
delay in wound healing, skin atrophy
what can be given in co-administration with glucocorticoids to reduce side effects
anti-mineralocorticoids
why are not all cells/DNA affected by steroids(glucocorticoids)
some DNA exists as chromatin, which is not accessible to steroids, so only 1/10th actually available
