PoH: Essential Pharmacology Flashcards
Why do we need cells to communicate?
To coordinate complex activities
5 ways cells may respond to signal transduction
Secretory activity, contractile activity, metabolism, membrane permeability, rate of proliferation or differentiation
Which type of cell-surface receptor uses ligand binding to open or close the channel?
Receptor-Channel
Which type of cell-surface receptor uses ligand-binding to it, to open an ion channel or alter enzyme activity?
G Protein-Coupled Receptor
Name the two types of catalytic receptors
Receptor-enzyme and integrin receptor
What type of cell surface receptor uses ligand binding to activate an intracellular enzyme?
Receptor-enzyme (a type of catalytic receptor)
What type of cell-surface receptor uses ligand binding to alter enzymes or the cytoskeleton?
Integrin receptor (a type of catalytic receptor)
How do cells achieve intracellular communication?
By chemical signalling molecules acting on specific receptors
Where does intracellular calcium (Ca2+) come from?
Hint: There’s 3 ways (one relating to where it’s stored in the cell, one from how we get it into the cell, and one on how we stop it from leaving)
Internal stores from the ER
From outside the cell via voltage-gated or ligand-gated Ca2+ channels
Via inhibition of Ca2+ transport out of the cell
Define receptor, and explain how it relates to drugs
Receptors are proteins in a cell or on its surface which receive a signal. Drugs act by interacting with a binding site on a receptor
Define agonist and antagonist (relating to drugs)
Agonist - mimic normal effect on receptor
Antagonist - block normal action of receptor
Define affinity (relating to drug action)
Affinity - determined by strength of chemical interactions between drug and receptor
How does a change in drug affinity affect Ec50 and the location of the curve in a log graph?
Low Ec50 - curve moves right - high affinity
High Ec50 - curve moves left - low affinity
What does a dose-response curve show?
The dose-response curve shows the relationship between agonist concentration and effect. The higher the concentration, the higher the response, until it reaches saturation
Explain saturation in a dose-response curve
Saturation refers to the maximum speed at which a reaction can occur
