Chapter 4
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Which of the following routes of drug administration is not used for laboratory animals?
intravenous injection
subcutaneous injection
sublingual administration
intracerebroventricular administration
Which of the following is not true of depot binding?
It can delay the effects of a drug.
It can prolong the effects of a drug.
Albumin is a source of depot binding.
Kidneys are a source of depot binding.
The therapeutic index of a drug is
a measure of a drug's margin of safety.
the dose of a drug that produces toxic effects in 50 percent of animals.
very low for drugs such as Valium.
very high for barbiturates.
Which of the following is not true about repeated administration of a drug?
It can inhibit tolerance.
It can produce sensitization.
Withdrawal symptoms can appear after a person stops taking the drug.
Compensatory mechanisms may be engaged.
The placebo effect
shows that the mind can affect behavior without involving the brain.
is especially important in animal research.
has been analyzed through the use of drugs.
only occurs in people who can be hypnotized.
Select the incorrect statement.
When a drug acts as a precursor, it increases the production of a neurotransmitter, serving as an agonist.
If a drug inactivates enzymes responsible for the production of a neurotransmitter, it acts as an agonist.
Transporter molecules that fill synaptic vesicles may be blocked by a drug, which then serves as an antagonist.
Some antagonist drugs prevent the release of transmitter substance from terminal buttons.
A drug that mimics the effects of a transmitter substance acts as a
receptor blocker.
direct antagonist.
direct agonist.
indirect ligand.
Drugs that bind with postsynaptic receptors can serve as antagonists when they
cause ion channels to open.
depolarize cations.
prevent the synaptic vesicles from releasing transmitter substance.
bind with the receptors but do not open the ion channels.
Select the incorrect statement
Receptor blockers or direct antagonists refer to the same process.
Noncompetitive binding means that a molecule does not compete with molecules of the transmitter substance for the same binding site.
A drug that binds noncompetitively can act as an inverse antagonist.
Drugs that block presynaptic autoreceptors increase the release of the transmitter substance.
Which of the following is not true of presynaptic heteroreceptors?
They are contained in the first (presynaptic) terminal button of axoaxonic synapses.
Drugs can make them insensitive to the transmitter substance.
They can inhibit the opening of voltage-dependent calcium channels.
They can facilitate the opening of voltage-dependent calcium channels.
Drugs that bind with and block dendritic autoreceptors
produce an inhibitory hyperpolarization.
inhibit production of the transmitter substance.
disrupt the regulatory mechanism that controls the production of transmitter substance.
act as agonists.
Termination of the postsynaptic potential
can occur when molecules of the transmitter substance are taken back into the dendrite through reuptake.
can occur when molecules of the transmitter substance are destroyed by an enzyme.
may involve the enzyme choline acetyltransferase.
may be inhibited by drugs that act as antagonists.
Acetylcholine
has an excitatory effect on cardiac muscle fibers.
is found in the autonomic nervous system.
is deactivated by reuptake.
produces hyperpolarization in skeletal muscle fibers.
Select the incorrect statement.
Acetylcholine plays a role in attention and reinforcement.
Acetylcholine is made of acetate and choline.
Acetylcholine acts on both nicotinic and muscarinic receptors.
Acetylcholine has both inhibitory and excitatory effects on cells.
_____ blocks muscarinic receptors and _____ blocks nicotinic receptors.
Curare; atropine
Apomorphine; physostigmine
Atropine; curare
Tyrosine; atropine
Which of the following is not a monoamine neurotransmitter?
tyrosine
serotonin
norepinephrine
dopamine
Which of the following statements is true?
Dopamine is synthesized from the amino acid tryptophan.
Dopamine is involved in arousal and sleep.
Dopamine stimulates at least five different kinds of ionotropic receptors.
Dopaminergic synapses are lacking in Parkinson's disease and overactive in schizophrenia.
The function of monoamine oxidase (MAO) is to
facilitate synthesis of the monoamines.
destroy excess amounts of the monoamines.
block the reuptake of the monoamines.
transport the monoamines down the axon to the terminal buttons.
Which drug was the first to receive widespread use as an effective treatment for the symptoms of schizophrenia?
Valium
chlorpromazine
atropine
lithium carbonate
Serotonergic neurons
are involved in the symptoms of schizophrenia.
help regulate blood pressure.
are involved in the control of dreaming.
are involved with balance and walking.
Glutamic acid, GABA, and glycine
may be the three most common transmitter substances in the CNS.
appeared late in the evolutionary process.
circulate through the brain in the cerebrospinal fluid.
are the principal excitatory transmitter substances of the brain.
All of the following act on the GABA receptor complex except
NMDA.
benzodiazepines.
barbiturates.
alcohol.
Many peptides that are released at the same time as a transmitter substance may serve to regulate the
sensitivity of postsynaptic receptors to the transmitter substance.
reuptake of the transmitter substance.
axoplasmic flow to the terminal buttons.
metabolism of the brain.
Endogenous opioids are
by-products of the synthesis of transmitter substances.
steroids synthesized from cholesterol.
neuromodulators produced in the brain.
hormones secreted by many tissues of the body.