Chapt 4: Pharmacology Flashcards
Pharmacokinetics
the process by which drugs are absorbed, distributed within the body, metabolized and excreted
routes of administration
- Intravenous Injection
- Intraperitoneal Injection
- Intramuscular Injection
- Subcutaneous Injection
- Oral Administration
- Sublingual Administration
- Intrarectal Administration
- Inhalation
- Topical Administration
- Intracerebral Administration
- Intracerebroventricular Administration
Intravenous Injection (IV)
Injection of a substance direction into a vein
Intraperitoneal Injection (IP)
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 that it is sswallowed
Sublingual Administration
Administration of a substance by placing it beneath the tongue
Intrarectal Administration
administration of a susbstance into the rectum
inhalation
administration of a vaporous substance into the lungs
Topical Administration
administration of a substance directly onto the skin or mucous membrane
Intracerebral Administration
administration of a substance directly into the brain
Intracerebroventricular Administration (ICV)
administration of a susbtance into one of the cerebral ventricles
Protein Binding Means?
“Protein binding can enhance or detract from a drug’s performance. As a general rule, agents that are minimally protein bound penetrate tissue better than those that are highly bound, but they are excreted much faster… Agents that are highly protein bound may, however, differ markedly from those that are minimally bound in terms of tissue penetration and half-life. “
Source: Protein Binding: what does it mean?
DOI: 10.1177/106002808902300706
Lipid Solubility
ease with drug molecules are soluble in fa
depot binding
binding of a drug with various tissues of the body or with proteins in the blood
albumin
a protein found in the blood; serves to transport free fatty acids and can bind with some lipid-soluble drugs
inactivation and excretion
- enzymes deactivate drugs (e.g. liver)
2. drugs are eventually excreted (e.g. kidneys)
Dose Responsive Curve
- a graph of the magnitude of an effect of a drug as a function of the amount of drug administered
- at a plateau there’s no further effect despite increasing the drug
Question: do drugs have only one effect?
no, many drugs have more than one effect
Question: What should be taken into consideration when determining the effective dose for treatment?
the different effects of a drug
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
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 symptoms
the appearance of symptoms opposite to those produced by a drug when the drug is administered repeatedly and then suddenly no longer taken
placebo effects
an inert substance that is 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 neurotransmitter on the postsynaptic cell
agonist
a drug that facilitates the effects of a particular neurotransmitter on the postsynaptic cell
what is effected by agonists and antagonists?
production, storage, release, (binding), re-uptake and destruction of neurotransmitters
drug affects on synaptic transmission (agonists)
- drug serves as precursor
- drug stimulates release of neurotransmitter
- drug stimulates postsynaptic receptors
- drug blocks auto receptors; increases synthesis/ release of neurotransmitters
- drugs blocks re-uptake
- drug inactivates acetylcholinestrase (the enzyme whose purpose is to terminate synaptic transmission)
Drug affects on synaptic transmission (antagonist)
- drug inactivates synthetic enzyme; inhibits synthesis of neurotransmitter
- drug prevents storage of neurotransmitter in vesicles
- drug inhibits release of neurotransmitter
- drug blocks postsynaptic receptors
- drug stimulates auto receptors; inhibits synthesis/ release of neurotransmitter
direct agonist
a drug that binds with and activates a receptor
direct antagonist
a drug that binds with a receptor but does not activate it; prevents the natural ligand from binding with the receptor
ligand
a molecule that binds to another molecule
or
an ion or molecule attached to a metal atom by coordinate bonding
noncompetitive 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 site for the principal ligand
presynaptic heteroreceptor
a receptor located in the membrane of a terminal button that receives input from another terminal button by means of an axoxonic synapse; binds with the neurotransmitter released by the presynaptic terminal button
heteroreceptor
terminal receptors for other transmitters that may act either to stimulate or inhibit release at that terminal
acetylcholine (ACh)
primary neurotransmitter secreted by efferent axons of the PNS
efferent neurons
motor neurons that carry neural impulses away from the CNS and toward muscles to cause movement
afferent neurons
sensory neurons carry nerve impulses from sensory stimuli toward the CNS and brain
major concentrations of ACh in the CNS include:
- dorsolateral pons (role in REM sleep)
- basal forebrain (role in learning)
- medial septum (role in memory)
botulinum toxin
an ACh antagonist; prevents release by terminal buttons
black widow spider venom
a poison produced by the black widow spider that triggers the release of acetylcholine
hemicholinium
a drug that inhibits the uptake of chonline
neogstigmine
a drug that inhibits the activity of acetylcholinesterase
nicotinic ACh receptor
an ionotripic ACh receptor that is stimulated by nicotine and blocked by curare
muscarinic ACh receptor
a metabotropic ACh receptor that is stimulated by muscarine and blocked by atropine
the monoamines
a class of amines that includes indolamine, such as serotonin, and catecholamines, such as dopamine, norepinephrine, and epinephrine
dopamine
- a catecholamine synthesized from L-DOPA
- major CNS dopaminergic systems include
a) nigrostriatal system (role in movement)
b) mesolimbic system (role in reinforcement/ reward)
c) mesocortical system (role in short-term memory, planning and problem solving)
methylphenidate
a drug that inhibits the reuptake of dopamine
monoamine oxidase (MAO)
a class of enzymes that destroy the monoamines
deprenyl
a drug that blocks the activity of MAO-B; dopamine agonist
chlorpromazine
a drug that reduces the symptoms of schizophrenia by blocking dopamine (D sub 2) receptors
role of monoamine oxidase
MAO converts dopamine to an inactive substance when not stored in synaptic vesicles
norepinephrine
one of the catecholamines; a neurotransmitter found in the brain and in the sympathetic division of the ANS
epinephrine
one of the catecholamines; a hormone secreted by the adrenal medulla; serves also a neurotransmitter in the brain
moclobemide
a drug that blocks the activity of MAO-A; acts as a noradrenergic agonist
locus coeruleus
a dark-colored group of noradrenergic cell bodies located in the pons near rostral end of the floor of the fourth vehicle
serotonin
an indolamine neurotransmitter; also called 5-hydroxytyptamine (5-HT)
PCPA
a drug that inhibits the activity of typtophan hydroxylase and thus interferes with the synthesis of 5-HT
Fluoxetine (Prozac)
a drug that inhibits the re-uptake of 5-HT
Fenfluramine
a drug that stimulates the release of 5-HT
MDMA
a drug that serves as a noradrenergic and serotonergic agonist, aka ecstacy; has excitatory and hallucinogenic effects
Glutamate
an amino acid; the most important excitatory neurotransmitter in the brain
NMDA receptor
a specialized ionotropic glutamate receptor that controls a calcium channel that is normally blocked by Mg^2+ ions; has several other binding sites
AMPA receptor
an ionotropic glutamate receptor that controls a sodium channel; stimulated by AMPA
AP5
a drug that blocks the glutamate binding site on NMDA receptors
PCP
phencyclidine; a drug that binds with the PCP binding site of the NMDA receptor and serves as an indirect antagonist
GABA
an amino acid; the most important inhibitory neurotransmitter in the brain. Produced from glutamic acid by the action of an enzyme called GAD
benzodiazepine
a category of anxiolytic drugs and indirect agonist for the GABA receptor
anxiolytic
an anxiety reducing effect
adenosine
a nucleoside; a combination of ribose and adenine; serves as a neuromodulator in the brain
caffeine
a drug that blocks adenosine receptors
caffeine in common beverages
- coffee 85mg per 5 oz
- decaf coffee 3mg per 5 oz
- tea (3 min steep) 28 mg/ 5oz
- hot chocolate 30 mg/ 5oz
- cola 30-45/12 oz
- Baking chocolate 36 mg/oz
- milk chocolate 6 mg/oz
