Altering Neurotransmission Flashcards
Agonists
INCREASE neurotransmission effects
Antagonists
DECREASE neurotransmitter effects
Drugs Fit Like Keys
Each transmitter interacts with a variety of different receptor subtypes
Binding Affinity
The degree of chemical attraction between a ligand and a receptor
Efficacy (intrinsic activity)
The ability of a bound ligand to activate the receptor
Dose-Response Curve (DRC)
A graph of the relationship between drug doses & the effects
Biotransformation
Produces active metabolites that may produce side effects
Blood-Brain Barrier
Tight junctions between the cells of blood vessels in the CNS prevent the movement of large molecules; can limit drug availability.
Metabolic Tolerance
Organ systems become more effective at eliminating the drug
Conditioned Tolerance
Adaptation to the environment in which a drug is typically administered
Functional Tolerance
Target tissue may alter its sensitivity to the drug by changing the number of receptors.
-Down-regulation in response to an agonist - few receptors
-Up-regulation in response to an antagonist - more receptors
Cross-Tolerance
Tolerance to one drug is generalized to other drugs in its class
Production
- Agonists: precursors
- Antagonists: block synthesizing enzymes
Release
- Agonists: increase Ca++
- Antagonists: block. Ca++ ion channels
Clearance
- Agonists: block the transporter or degradation enzymes
