Drug receptor interactions Flashcards
Define drug
A chemical substance that interacts with a biological system to produce a physiological effect.
What are some drug target sites
Receptors
Ion channels
Transport systems
Enzymes
Give examples of drugs that target receptors
Acetylcholine (agonist)
atropine (antagonist)
Describe receptor target sites
Proteins within cell membranes
Activated by NT or hormone
Drugs are agonists or antagonists
Describe ion channel target sites and give the 2 types
Selective pores that allow ion transfer down a gradient
Voltage sensitive e.g. VSCC
Receptor-inked e.g. nAChR
Give examples of drugs that target ion channels
Local anaesthetics
Calcium channel blockers
Give examples of drugs that target transport systems
Tricyclic anti-depressants
Cardiac glycosides
Give examples of transport systems targets
Na+/K+-ATPase
NA ‘uptake 1’
Give examples of how drugs interact with enzymes
Enzyme inhibitors e.g. anticholinesterases
False substrates e.g. methyldopa
Prodrugs e.g. trichloroethanol
What does potency of a drug depend on
Affinity
Efficacy
What are the types of drug-receptor interactions
Agonist
Antagonist
Full agonist
Partial agonist
Describe the affinity and efficacy of receptor antagonists
Affinity but no efficacy
What are the 2 types of receptor antagonist, how do they affect the D-R curve and give examples
Competitive - D-R curve shifts to right
Atropine, propanolol
Irreversible - insurmountable
Hexamethonium
Give examples of non-specific drugs
Antacids
Osmotic purgatives
