Lecture 3 Principles of Psychopharmacology Flashcards
Psychopharmacology
- The study of the effects of drugs on the nervous system and on behavior
Drug effects
- The changes a drug produces in an animal’s physiological process and behavior
Sites of Action
- The locations at which molecules of drugs interact with molecules located on or in cells of the body, thus affecting some biochemical processes of these cells
Pharmacokinetics
- The process by which drugs are absorbed, distributed within the body, metabolized, and excreted
Intravenous Injection (IV)
- Injection of a substance directly into a vein
Intraperitoneal Injection (IP)
- The injection of a substance into the peritoneal cavity-the space that surrounds the stomach, intestines, liver, and other abdominal organs.
Intramuscular Injection (IM)
- Injection of a substance into a muscle
Subcutaneous Injection (SC)
- Injection of a substance into the space beneath the skin
Oral Administration
- Administration of a substance into the mouth, so it is swallowed
Sublingual Administration
- Administration of a substance by placing it beneath the tongue
Intrarectal Administration
- Administration of a substance into the rectum
Inhalation
- Administration of a vaporous substance into the lungs
Pharmocodynamics
- How the drug acts on the receptors
Topical Administration
- Administration of a substance absorbed through the skin
Intracerebral Administration
- Administration of a substance directly into the brain
Drug Effectiveness Dose-response curve
- Plots the magnitude of the effect of a drug as a function of the amount of the drug administered
Drug Effectiveness Therapeutic Index
- The ratio between the dose that produces the desired effect in 50% of the animals and the dose that produces toxic effects in 50% of the animals
Drug Effectiveness Affinity
- The readiness with which two molecules join together
Tolerance
- A decrease in the effectiveness of a drug that is administered repeatedly
Sensitization
- An increase in the effectiveness of a drug that is administered repeatedly
Withdrawal Symptom
- The appearance of symptoms opposite to those produced by a drug when the drug is administered repeatedly and then suddenly no longer taken
Placebo
- An inert substance given to an organism in lieu of a physiologically active drug;
- Used experimentally to control for the effects of mere administration of a drug
Antagonist
- A drug that opposes or inhibits the effects of a particular neurotrasmitter on the postsynaptic cell
Agonist
- A drug that facilitates the effects of a particular neurotransmitter on the postsynaptic cell
Direct Agonist
- A drug that binds with and activates a receptor. This drug mimics the effects of a neurotransmitter
Receptor Blocker
- A drug that binds with a receptor but does not activate it
- Prevents the natural ligand from binding with the receptor
Direct antagonist
- Synonym for a receptor blocker
Noncompetitve Binding
- Binding of a drug to a site on a receptor
- Does not interfere with the binding site for the principal ligand
Indirect Antagonist
- A drug that attaches to a binding site on a receptor and interferes with the action of the receptor
- Does not interfere with the binding of the priciple ligand
Indirect Agonist
- A drug that attaches to a binding site on a receptor and facilitates the action of the receptor
- Does not interfere with the binding site of the principal ligand
Diagram
Acetylcholine
- The primary neurotransmitter secreted by the efferent axons of the CNS
- All muscular movement is accomplished by the release of acetylcholine
- Appears to be involved in regulating REM sleep, perceptual learning, and memory
Acetyl-CoA
- Precursor A cofactor that supplies acetate for the synthesis of acetylecholine
Choline Acetyltransferase (ChAT)
- The enzyme that transfers the acetate ion from acetyl coenzyme A to choline, producing the neurotransmitter acetylcholine
Botulinum toxin
- An acetylcholine antagonist; prevents release by terminal buttons
Black Widow Spider Venom
- A poison produced by the black widow spider that triggers the release of acetylcholine
Neostigmine
- A drug that inhibits the activity of acetylcholinesterase
Nicotinic Receptor
- An ionotropic acetylcholine receptor that is stimulated by nicotine and blocked by curare
Muscarinic Receptor
- A metabotropic acetylcholine receptor that is stimulated by muscarine and blocked by atropine
Atropine
- A drug that blocks muscarinic acetylcholine receptors
Curare
- A drug that blocks nicotinic acetylcholine receptors and causes paralysis
Monoamines - Catecholamines
- Dopamine (DA)
- Norepinephrine (NE)
- Epinephrine
Monoamines - Indolamines
- Serotonin (5-HT)
Norepinephrine
Monoamine
- A class of amines that includes indolamines such as serotonin and catecholamines such as dopamine, norepinephrine, and epinephrine
Dopamine
- A neurotransmitter; one of the catecholamines
- Produces both excitatory and inhibitory postsynaptic potentials
- Implicated roles in movement, attention, learning, reinforcing effects of abused drugs
- Synthesized from tyrosine that we obtain from our diet
Monoamines-dopamine– L-DOPA
- The biologically active form of DOPA
- The precursor of the catecholamines
- Often used to treat Parkinson’s disease because of its role as a dopamine agonist
Monoamines-dopamine – Nigrostriatal System
- A system of neurons originating in the substantia nigra and terminating in the neostriatum (caudate nucleus and putamen of the basal ganglia)
- Appears to play a role in the control of movement
Monoamines-dopamine – Mesolimbic system
- A system of dopaminergic neurons originating in the ventral tegmental area and terminating in the nucleus accumbens, amygdala, and hippocampus
- Appears to play a role in the reinforcing effects of drugs that are commonly abused
Monoamines-dopamine – Mesocortical System
- A system of dopaminergic neurons originating in the ventral tegmental area and terminating in the prefrontal cortex
- Appears to influence formation of short-term memories, planning, and preparing strategies for problem solving
Brain Diagram
Monoamines-dopamine – Parkinson’s disease
- A neurological disease characterized by tremors, rigidity of the limbs, poor balance, and difficulty initiating movements
- Caused by degeneration of the nigrostriatal system
- Has been treated with L-DOPA
Monoamines-dopamine – AMPT (Alpha-methyl-p-tyrosine)
- A drug that blocks the activity of tyrosine hydroxylase and thus interferes with the synthesis of the catecholamines.
- Pheochromocytoma
Monoamines-dopamine – Reserpine
- A drug that interferes with the storage of monoamines in synaptic vesicles
- Serves as a monoamine antagonist
Monoamines-dopamine – Methylphenidate
- A drug that inhibits the reuptake of dopamine
- Also known as Ritalin
- Used to treat children with attention deficit disorder
Monoamines-dopamine – Monoamine Oxidase (MAO)
- A class of enzymes that destroy the monoamines; dopamine, norepinephrine, and serotonin
Monoamines-dopamine – Deprenyl (Selegiline)
- A drug that blocks the activity of MAO-B
- Acts as a dopamine agonist
Monoamines-dopamine – Chlorpromazine
- A drug that reduces the symptoms of schizophrenia by blocking dopamine D2receptors
Monoamines-norepinephrine (NE) – norepinephrine
- One of the catecholamines
- A neurotransmitter found in the brain and in the sympathetic division of the autonomic nervous system
Monoamines-norepinephrine – Epinephrine
- One of the catecholamines
- A hormone secreted by the adrenal medulla
- Serves as a neurotransmitter in the brain
Monoamines-norepinephrine
- Norepinephrine is synonymous with noradrenaline
- Found in neurons of the brain and the autonomic nervous system
- Almost every region of the brain receives input from noradrenergic neurons
- Implicatted to play central role in vigilance or attentiveness to events in the environment
Monoamines-norepinephrine – Fusaric Acid
- A drug that inhibits the activity of the enzyme dopamine-B-hydroxylase and thus blocks the production of norepinephrine
Monoamines-norepinephrine – Locus Coeruleus
- A dark-colored group of noradreneric cell bodies located in the pons near the rostral end of the floor of the fourth ventricle
Monoamines – Serotonin
- Serotonin is an indolamine neurotransmitter
- Also called 5-HT or 5-hydroxytryptamine
- Thought to play a role in the regulation of mood, the control of eating, sleep, dreaming, and arousal
- Also thought to be involved in the regulation of pain
- The amino acid tryptophan is the precursor of serotonin
Monoamines-serotonin (5-HT) – Fluoxetine (Prozac)
- A drug that inhibits the reuptake of 5-HT
- Used to treat depression, obsessive-compulsive disorder and some anxiety disorders
Monoamines-serotonin (5-HT) – Fenfluramine (Fen-Phen)
- A drug that stimulates the release of 5-HT
Monoamines-serotonin (5-HT) – LSD
- A drug that stimulates 5-HT2a receptors
Monoamines-glutamate – MDMA
- A drug that serves as a noradrenergic and serotonergic agonist, also known as “ecstasy”
- Has excitatory and hallucinogenic effects
Monoamines-glutamate – Glutamate
- An amino acid
- The most important excitatory neurotransmitter in the brain
Monoamines-glutamate – NMDA receptor
- A specialized ionotropic glutamate receptor that controls a calcium channel that is normally blocked by Mg2+ ions
- Has several other binding sites
Monoamines-glutamate – AMPA receptor
- An ionotropic glutame receptor that controls a sodium channel; stimulated by AMPA
Glutamate Ion channel
Amino Acids - The most common amino acid transmitters are:
- Glutamate
- Gamma-aminobutyric acid (GABA)
- Glycine
Amino acids-glutamate – Kainate receptor
- An ionotropic glutamate receptor that controls a sodium channel
- Stimulated by kainic acid
Amino acids-glutamate – Metabotropic glutamate receptor
- A category of metabotropic receptors sensitive to glutamate
Amino acids-glutamate – PCP (Phencyclidine)
- A drug that binds with the PCP binding site of the NMDA receptor and serves as an indirect antagonist of glutamate
Amino acids – GABA
- Gamma-aminobutyric acid is an amino acid
- GABA is the most important inhibitory neurotransmitter in the brain and spinal cord