Essential Pharmacology Flashcards
Give 2 examples of chemicals that are lipid soluble and can therefore reach intracellular receptors.
- steroid hormones
- NO
What does NO do?
- binds to soluble guanylyl cyclase
- generates cGMP as a second messenger which regulates cell activity
What are ionotropic receptors?
those where the receptor is also an ion channel
An example of a chemical activated by a G-proten coupled receptor is adenylyl cyclase. What does it produce?
cAMP
What does cAMP do?
regulates the activity of another enzyme, PKA which is a kinase enzyme
What does the G-protein coupled receptor that involves Phospholipase C do?
produces DAG that regulates PKC (a kinase) and IP3 that regulates Ca2+
Why are the Gprotein coupled receptors that involve the regulation of PKC and PKA important?
PKA and PKC are kinases that are used to phosphorylate, and therefore regulate, a whole host of cell proteins
What is one way of improving the efficacy of a drug?
increasing the amount of drug given (to a certain extent as eventually receptors become saturated)
What is the affinity of a drug determined by?
strength of chemical attraction between drug and receptor
What is EC50?
half maximal response when half available receptors are activated
What does a low EC50 indicate?
a high affinity
What is meant by efficacy?
how good the drug is at activating the receptor
What do agonist drugs do?
mimic normal effect of receptor
What do antagonist drugs do?
block normal action of receptor
What type of drug (in action) is salbutamol?
a selective agonist
