Basic Pharmacology Flashcards
What are the four types of cell membrane receptors?
Ion channel receptors (ionotropic); G-protein coupled receptors; tyrosine kinase (receptor is enzyme);
JAK coupled receptors (receptor plus enzyme)
What are the two enzymes and one protein acted on by G-protein coupled receptors?
Adenylyl Cyclase and Phospholipase C, ion channels
What are the two enzymes acted on by G-protein coupled receptors?
Adenylyl Cyclase and Phospholipase C
What effect does Adenylyl Cyclase activation by G-protein coupled receptors have?
Adenylyl Cyclase turns ATP –> cAMP; cAMP activated cAMP-dependent protein kinase A (PKA)
What effect does Phospholipase C activation by G-protein coupled receptors have?
Phospholipase C causes release of IP3 and DAG. IP3 causes Ca2+ release from endoplasmic reticulum, which adds to DAG effect to activate Protein Kinase C (PKC)
What is the role of kinases?
Kinases phosphorylate proteins and other molecules
What happens to the concentration-response graph and EC50 if a drug has a high affinity for its receptor?
Higher affinity causes quicker response for given concentration, so graph moves to the left and EC50 goes down
What happens to the concentration-response graph and EC50 if a drug has a low affinity for its receptor?
Lower affinity causes slower response for given concentration, so graph moves to the right and EC50 goes up
What does EC50 measure?
EC50 measures half the maximal response for a drug on the concentration-response curve
What is meant by drug efficacy?
The ability of a drug to fully activate a receptor
What is meant by drug affinity?
The chemical attraction between a drug and its target receptor
What two main factors impact on drug response?
Drug affinity to receptor and drug efficacy
What is a selective agonist/antagonist?
A drug which only targets certain subtypes of receptor (eg only beta 1 adrenergic receptors, but not all adrenergic receptors)
How does adding an antagonist alter the concentration-response curve?
It will shift the curve to the right, since the antagonist presence will result in more agonist needed to reach the same effect as agonist presence on its own
