L3 - How Drugs Work - Part 1 Flashcards
1
Q
What is characteristic of ions across a membrane
A
- large difference in concentration
- under strict regulation
2
Q
cytosolic
A
intracellular surfacce of the membrane
3
Q
intregral proteins
peripherial proteins
A
- integral
- intrinsic
- transmembrane
- peripheral
- extrinsic
4
Q
action of drugs in opening ion channels?
A
- bind to complementary receptor on protein
- causes channel to open
- mainly integral proteins
5
Q
specififity of drugs
A
- need to fit particular receptor
- side effects often caused by drugs not being selective
- then causing changes in different cells
- complemtary to structure of receptor
6
Q
what are the 4 stages a drug goes through
A
- absorbtion
- distribution
- metabolism
- needed for inactivation and excretion
- excretion
7
Q
where are receptirs located
A
- outer membrane of the cell
- enzymes located within the cell
8
Q
receptor numbers
A
- disease or drug use can affect receptor numbers
- therefore drug has a decreased effect
- can be increased (up-regulation) and decreased (down-regulation
9
Q
ligand
A
- chemicals which bind to the receptors
10
Q
agonist
A
- ligand with two important properties
- affinity
- strength of binding to receptor
- efficacy
- intrinsic activity
- induces a conformational change in the receptor
- 3d changes
- (triggers response in a cell)
11
Q
antagonist
A
- ligand which blocks the receptor
- has affinity but not efficacy
- unable to activate receptors
- can be used to prevent agonists from binding
12
Q
cellular signalling and altering cellular signalling and drugs
A
- stimulus → receptor (on target cell) → physiological response
- aberrant cellular signalling underlies disease processes
- many drugs targeted to cellular signalling processes
- improved knowledge of cellular signalling processes continues to identify novel targets for drug design and improved therapy
13
Q
signal transduction
how does it work
what does it enable
how do drugs affect it
A
- intercellular signal chemical does not enter the cell
- binding of the signal chemical to its receptor initiates a series of chemical changes in the cell
- chemical changes alter physiology of the cell
- signal transduction enables amplification
- drugs can alter these effects to induce an alteration in the cellular response
14
Q
what are the different ways signal transduction may occur
A
- direct opening of ion channels
- direct activation of an enzyme
- indirect activation/inactivation of enzyme
- indirect opening/closing of ion channel
- involves a G-protein (molecular switch)
- intracellular second messangers involved
