General principles of pharmacology Flashcards
What is pharmacology?
-the study of how drugs affect tissue function
-this is split up into pharmacodynamics (what the drug does to the body) and pharmacokinetics (what the body does to the drug)
What is a drug?
A drug is a chemical that affects physiological function
How do drugs exert their effects?
to affect tissue function drugs need to bind to particular components of cells tissues
What is drug selectivity?
-for a drug to function therapeutically it must act selectively on certain targets
-e.g some beta blockers are described as cardio-selective
What are the 4 different levels that drugs act at?
-molecular- immediate target for drug
-cellular- biochemical components of cell that participate in signal transduction process
-tissue- how the function of the specific tissue is altered
-system- how the function of the organ system is altered
How do drugs interact with their targets?
they interact to initiate a biological change or physiological response, often mimicking or blocking chemical signals found within the body e.g hormones or neurotransmitters
What are the 4 different types of protein targets?
-enzymes
-carrier/ transport
-ion channels
-receptors
How do drugs work with ion channel protein targets?
-drugs can act to facilitate opening or blocking of the channel
How do drugs work with enzymes as protein targets?
-drugs often act as inhibitors at enzymes e.g aspirin and drugs like captopril
How do drugs work with carrier/ transporter protein targets?
-drugs can inhibit or facilitate transport of molecules that use carriers e.g furosemide inhibits a carrier for Na/K/Cl in the kidney
How do drugs work with non target proteins e.g plasma proteins?
-some drugs bind to plasma proteins such as albumin
-plasma proteins act as transporters, when a drug is bound to a plasma protein it is not free in the plasma
What is a receptor? give examples
-a receptor is a protein found naturally in the body that acts as a recognition site for the body’s natural chemical signals
-e.g neurotransmitters, hormones, inflammatory mediators
What is an agonist drug reaction?
if a drug mimics the natural chemical signals, producing the same or an enhanced effect as the natural chemical signal e.g insulin
what is an antagonist drug reaction?
if a drug blocks the natural chemical signals preventing the effect of natural chemical signals
Explain what the two components interactions between drugs and receptors can be divided into?
-binding= binding of a drug to a receptor, governed by affinity (likelihood of drug binding to receptor)
-activation= induction of a response
-this is governed by efficacy (likelihood of the bound drug to elicit a response)
