Bio psych chapter 4

A type of endogenous peptide that mimics the effects of morphine in binding to opioid receptors and producing marked analgesia and reward.

opioid peptide

A receptor that responds to endogenous opioids and/or exogenous opiates.

opioid receptor

An extract of the seedpod juice of the opium poppy, Papaver somniferum. Drugs based on opium are potent painkillers.

opium

A substance that mimics or potentiates the actions of a transmitter or other signaling molecule.

agonist

A neurotransmitter based on modifications of a single amino acid nucleus. Examples include acetylcholine, serotonin, and dopamine.

amine neurotransmitter

A neurotransmitter that is itself an amino acid. Examples include GABA, glycine, and glutamate.

amino acid neurotransmitter

A molecule that resembles the structure of the catecholamine transmitters and enhances their activity.

amphetamine

Having painkilling properties.

analgesic

An endogenous substance that binds the cannabinoid receptor molecule.

anandamide

1. A substance that blocks or attenuates the actions of a transmitter or other signaling molecule. 2. A muscle that counteracts the effect of another muscle.

antagonist

A drug that relieves the symptoms of depression. Major categories include monoamine oxidase inhibitors, tricyclics, and selective serotonin reuptake inhibitors.

antidepressant

Also called neuroleptic. Any of a class of antipsychotic drugs that alleviate symptoms of schizophrenia, typically by blocking dopamine receptors.

antipsychotic

A substance that is used to combat anxiety. Examples include alcohol, opiates, barbiturates, and the benzodiazepines.

anxiolytic

Also called atypical neuroleptic. An antipsychotic drug that has actions other than or in addition to the dopamine D2 receptor antagonism that characterizes the typical antipsychotics.

atypical antipsychotic

A receptor for a synaptic transmitter that is located in the presynaptic membrane and tells the axon terminal how much transmitter has been released.

autoreceptor

Also called neuropeptide. A neurotransmitter consisting of a short chain of amino acids.

peptide neurotransmitter

A midbrain region involved in pain perception.

periaqueductal gray

Collective name for all the factors that affect the movement of a drug into, through, and out of the body.

pharmacokinetics

Referring to the region of a synapse that receives and responds to neurotransmitter.

postsynaptic

Located on the "transmitting" side of a synapse.

presynaptic

A string of nuclei in the midline of the midbrain and brainstem that contain most of the serotonergic neurons of the brain.

raphe nuclei

A neurotransmitter that is released by the postsynaptic region, diffuses back across the synapse, and alters the functioning of the presynaptic neuron.

retrograde transmitter

The process by which released synaptic transmitter molecules are taken up and reused by the presynaptic neuron, thus stopping synaptic activity.

reuptake

An antidepressant drug that blocks the reuptake of transmitter at serotonergic synapses.

selective serotonin reuptake inhibitor (SSRI)

Referring to cells that use serotonin as their synaptic transmitter.

serotonergic

A synaptic transmitter that is produced in the raphe nuclei and is active in structures throughout the central nervous system.

serotonin (5-HT)

A drug that enhances the excitability of neurons.

stimulant

Also called ligand-gated ion channel. A receptor protein containing an ion channel that opens when the receptor is bound by an agonist.

ionotropic receptor

A brainstem region that provides some of the norepinephrine-containing projections of the brain.

lateral tegmental area

A substance that binds to receptor molecules, such as a neurotransmitter or drug that binds postsynaptic receptors.

ligand

A small nucleus in the brainstem whose neurons produce norepinephrine and modulate large areas of the forebrain. Compare substantia nigra.

locus coeruleus

The form of drug tolerance that arises when repeated exposure to the drug causes the metabolic machinery of the body to become more efficient at clearing the drug.

metabolic tolerance

A receptor protein that does not contain ion channels but may, when activated, use a second- messenger system to open nearby ion channels or to produce other cellular effects.

metabotropic receptor

An enzyme that breaks down monoamine neurotransmitters, thereby inactivating them.

monoamine oxidase (MAO)

An opiate compound derived from the poppy flower.

morphine

Also called simply transmitter, synaptic transmitter, or chemical transmitter. A signaling chemical, released by a presynaptic neuron, that diffuses across the synaptic cleft to alter the functioning of the postsynaptic neuron.

neurotransmitter

Also called simply receptor. A specialized protein, often embedded in the cell membrane, that selectively senses and reacts to molecules of a corresponding neurotransmitter or hormone.

neurotransmitter receptor

A compound found in plants, including tobacco, that acts as an agonist on a large class of cholinergic receptors.

nicotine

Referring to cells using norepinephrine (noradrenaline) as a transmitter.

noradrenergic

Also called noradrenaline. A neurotransmitter that is produced and released by sympathetic postganglionic neurons to accelerate organ activity. It is also produced in the brainstem and found in projections throughout the brain.

norepinephrine (NE)

A region of the forebrain that receives dopaminergic innervation from the ventral tegmental area, often associated with reward and pleasurable sensations.

nucleus accumbens

A brainstem structure that innervates the basal ganglia and is a major source of dopaminergic projections.

substantia nigra

The cellular location at which information is transmitted from a neuron to another cell.

synapse

A specialized membrane component that returns transmitter molecules to the presynaptic neuron for reuse.

transporter

An antidepressant that acts by increasing the synaptic accumulation of serotonin and norepinephrine.

tricyclic antidepressant

A compensatory increase in receptor availability at the synapses of a neuron.

up-regulation

A portion of the midbrain that projects dopaminergic fibers to the nucleus accumbens.

ventral tegmental area (VTA)

An uncomfortable symptom that arises when a person stops taking a drug that he or she has used frequently, especially at high doses.

withdrawal symptom

Also called acid. Lysergic acid diethylamide, a hallucinogenic drug.

LSD

Also called Ecstasy. 3,4-Methylenedioxymethamphetamine, a drug of abuse.

MDMA

A neurotransmitter that is produced and released by the autonomic nervous system, by motoneurons, and by neurons throughout the brain.

acetylcholine (ACh)

An early anxiolytic drug and sleep aid that has depressant activity in the nervous system.

barbiturate

A region, ventral to the basal ganglia, that is the major source of acetylcholine in the brain and has been implicated in sleep.

basal forebrain

Any of a class of antianxiety drugs that are agonists of GABAA receptors in the central nervous system. One example is diazepam (Valium).

benzodiazepine

Also called simply affinity. The propensity of molecules of a drug (or other ligand) to bind to receptors. Drugs with high affinity for their receptors are effective even at low doses.

binding affinity

Referring to a substance, usually a drug, that is present in the body in a form that is able to interact with physiological mechanisms.

bioavailable

The process in which enzymes convert a drug into a metabolite that is itself active, possibly in ways that are substantially different from the actions of the original substance.

biotransformation

The protective property of cerebral blood vessels that impedes the movement of some harmful substances from the blood stream into the brain.

blood-brain barrier

A region of cortex lying below the surface, within the lateral sulcus, of the frontal, temporal, and parietal lobes.

insula

Referring to cells that use acetylcholine as their synaptic transmitter.

cholinergic

A drug of abuse, derived from the coca plant, that acts by enhancing catecholamine neurotransmission.

cocaine

A condition in which the development of tolerance for one drug causes an individual to develop tolerance for another drug.

cross-tolerance

The major active ingredient in marijuana.

delta-9-tetrahydrocannabinol (THC)

A drug that reduces the excitability of neurons. Compare stimulant.

depressant

A monoamine transmitter found in the midbrain—especially the substantia nigra—and in the basal forebrain.

dopamine (DA)

Referring to cells that use dopamine as their synaptic transmitter.

dopaminergic

A formal graph of a drug's effects (on the y-axis) versus the dose given (on the x-axis).

dose-response curve (DRC)

A compensatory decrease in receptor availability at the synapses of a neuron. Compare up-regulation.

down-regulation

Also called simply tolerance. A condition in which, with repeated exposure to a drug, an individual becomes less responsive to a constant dose.

drug tolerance

One of the three kinds of endogenous opioids. Compare endorphin and enkephalin.

dynorphin

Unpleasant feelings; the opposite of euphoria.

dysphoria

Also called intrinsic activity. The extent to which a drug activates a response when it binds to a receptor. Receptor antagonist drugs have low efficacy; receptor agonists have high efficacy.

efficacy

An endogenous ligand of cannabinoid receptors, thus a marijuana analog that is produced by the brain.

endocannabinoid

Produced inside the body. Compare exogenous.

endogenous

Any of a class of opium-like peptide transmitters that have been referred to as the body's own narcotics. The three kinds are enkephalins, endorphins, and dynorphins.

endogenous opioid

One of the three kinds of endogenous opioids.

endorphin

One of the three kinds of endogenous opioids. Compare dynorphin and endorphin.

enkephalin

A cellular process that results in the release of a substance into the extracellular space.

exocytosis

Arising from outside the body. Compare endogenous.

exogenous

A disorder, including intellectual disability and characteristic facial abnormalities, that affects children exposed to too much alcohol (through maternal ingestion) during fetal development.

fetal alcohol syndrome

The form of drug tolerance that arises when repeated exposure to the drug causes receptors to be up-regulated or down-regulated. Compare metabolic tolerance.

functional tolerance

A widely distributed amino acid transmitter, the main inhibitory transmitter in the mammalian nervous system. See Table 4.1.

gamma-aminobutyric acid (GABA)

A neurotransmitter that is a soluble gas. Examples include nitric oxide and carbon monoxide. Usually gas neurotransmitters act, in a retrograde fashion, on presynaptic neurons.

gas neurotransmitter

An amino acid transmitter, the most common excitatory transmitter.

glutamate

A drug that alters sensory perception and produces peculiar experiences.

hallucinogen

Diacetylmorphine, an artificially modified, very potent form of morphine.

heroin