Chapter 4 Flashcards
(46 cards)
1
Q
4 major categories of neurotransmitters
A
- monoamines
- amino acids
- peptides
- other
2
Q
monamines
A
- contains a single “mono” amine group
ex. include catecholamine (a group composed of dopamine, norepinephrine, and epinephrine) and indolamines (represented by the neurotransmitter serotonin)
3
Q
Dopamine
A
- produced in the substantia nigra and central tegmental area
- involved in movement, reward system, and increased vigilance
4
Q
nigrostriatal pathway
A
pathway from the substantia nigra to the striatum
5
Q
mesolimbic pathway
A
pathway from the ventral tegmental area to the brain reward area
6
Q
Norepinephrine
A
- produced in locus coeruleus
- involved in increased vigilance, focused attention, and enhanced energy
7
Q
locus coeruleus
A
a brainstem area involved in arousal, and in sympathetic nerves
8
Q
epinephrine
A
- structurally similar to norepinephrine but is releases from the adrenal glands (sits atop the kidney)
- response to acute stress
9
Q
serotonin
A
tassa
- affects mood regulation
- sleep/wake cycles
- temperature regulation
- sexual activity
- aggression
10
Q
most abundant neurotransmitter in the CNS?
A
amino acid neurotransmitters
include:
- glutamate
- GABA
- glycine
11
Q
glutamate
A
main excitatory NT
- causes excitatory postsynaptic potentials
- involvement in synaptogenesis (brain plasticity mechanisms) as neural networks are formed
- -> once formed, glutamate plays a role in strengthening existing synapses, a process facilitating learning and memory
12
Q
Gamm (y)-aminobutyric acid (GABA)
A
- inhibitory neurotransmitter in the brain
- leads to seizures and death
subject to activation by various ingested substances - alcohol, a GABA agonist, or any drug that mimics or enhances the effects of specific neurotransmitters –> activation results in the inhibition of the brain’s cognitive and behavioral systems
13
Q
two types of receptors that glutamate molecules activate
A
- NMDA receptor
- AMPA receptor
14
Q
Glycine
A
- inhibitory neurotransmitter (same as GABA, but it’s in the spinal cord and brainstem)
15
Q
Peptides
A
- composed of ~3-40 amino acids
include:
- oxytocins and vasopressin
- endorphins
16
Q
Other neurotransmitters:
Acetylcholine (ACh)
A
synthesized from acetyl coenzyme A (from metabolism) and choline (from metabolism and diet)
- involved in motor functions and parasympathetic functions outside of the CNS
- involved in memory and cognitive functions inside the CNS
- -> nitric oxide and carbon monoxide have been found to alter synaptic function
17
Q
Goal of Neuropsychopharmacology
A
identify specific drugs that interact with the nervous system to alter behavior that has been disrupted by disease, injury, or environmental factors
18
Q
Psychoactive drug
A
affect neural transmission by enhancing (agonists) or blocking (antagonists) the actions fo natural transmitters in the synpase
19
Q
Antagonist
A
- block or decrease the effects of specific neurotransmitters
- block receptor sites
- increase the speed of neurotransmitter removal from synapse
- decrease production of neurotransmitters
ex. beta (B)-blockers decrease the effects of epinephrine, typically experienced during the stress response
20
Q
Agonist
A
- mimic or enhance the effects of specific neurotransmitters
- stop the removal of neurotransmitters from the synapse
- increase the production of neurotransmitters
ex. alcohol
21
Q
efficacy
A
ability to produce desired effects for a targeted condition
- most important goal when developing drugs
22
Q
How to test efficacy
A
- controlled study involving a placebo
- -> placebos may cause the patients to believe that the treatment will improve their condition (placebo effect)
- blind studies, meaning that patients do not know to which group they have been assigned
- double-blind studies, in which neither the patients nor the researchers know the group assignments
23
Q
For a drug to be considered a safe and effective treatment option for a specific disorder, what questions must be investigated and eventually answered
A
- route of administration
- absorption and distribution
- binding
- inactivation
- excretion
24
Q
route of administration
A
- inhalation, injection, or oral administration in pill form
- dose-response curves should be established
25
dose-response curves
- is a graph of the relationship b/n drug doses and the effects
- determines the lowest amount of drugs necessary to produce optimal responses
- a tool to understand pharmacodynamics--focuses on what does the drug does to the body: the effects of the drug and the mechanism of how the drug works
26
absorption and distribution
- which areas of the brain does the drug effect?
| - how quickly do these effects occur?
27
binding
in addition to the active target site for which the drug was developed where else does it bind or find itself
28
inactivation
what metabolic processes eventually make the drug inactive
| - most drugs are metabolized by the liver via the actions of specific enzymes
29
excretion
how are the substances produced by metabolism eliminated from the body
30
ED50 values
- relative potency of two drugs can be compared by their ED50 values
- drug that acts at a lower does is obviously stronger
- the therapeutic index is the separation b/n the effective dose and a toxic one
31
endorphins
type of peptide neurotransmitter that are involved in both pain and reward processes
32
oxytocin and vasopressin
oxytocin - females
vasopressin - males
both are involved in the regulation of specific fluids and social relationships
33
4 major drug types
- stimulant
- depressant
- narcotic
- psychedelic
34
stimulate
- drugs that facilitate arousal
| ex. caffeine, and cocaine
35
Cocaine
- combats the effects of hunger and fatigue
- affects dopamine in the rewards system and motor systems to produce many of tis effects
- effect include euphoria, a sense of increase energy, heightened mental alertness, and feelings of competence and power
- once it enters the CNS, cocaine blocks the reuptake of three monoamine neurotransmitters: dopamine, norepinephrine, and serotonin
- -> cocaine binds to the proteins that act as transporters for neurotransmitter reuptake back into the presynaptic membrane
36
caffeine
- most widely used psychoactive drug
- produces psychoactive effects by blocking receptors of adenosine (an inhibitory neurotransmitter)
- -> by blocking adenosine, caffeine consumption may result in an overall increase in excitatory neurotransmitter releases
- -> adenosine works to match the rate of energy supply with energy consumption and, if called for, decrease the firing rate of neurons
- adenosine agonists activate receptors and lead to sleep, whereas adenosine antagonists, such as caffeine, suppress the activation of the receptor, keeping the person awake
37
Depressant
drugs that suppress arousal
ex. alcohol
38
Alcohol
- Most used psychoactive drug in the United States, is the most abused drug
- Low doses include an improved mood, drowsiness, and increased self-confidence, as well as impaired judgement and motor coordination
- High doses allow for further cognitive and reflexive impairment to occur
- Alcohol causes the individual’s CNS to slow down, leading to extreme confusion and disorientation, as well as slow and irregular breathing patterns
39
Narcotic
ex. heroin and fentanyl
40
Heroin
"to sleep"
- manufactured form of morphine, highly potent when injects
- affects the reward system, brain stem, and spinal cord
- very dangerous and should only be used for severe pain
- feel nauseous at first b/c your body says to get rid of the poison
41
What are the two main affected areas of heroin?
1. Mesolimbic system (VTA & NA) ~ Euphoria
- reward via dopamine release
- habit, addition formation
2. Brainstem/Spinal Cord ~ Analgesia (This is what kills in an overdose. Heroin will slow breathing and heart function to the point of lethality.)
- Pain pathway
- Wakefulness, breathing, BP and alertness
42
Fentanyl
- heroin's synthetic and much stronger cousin
- much more dangerous
- -> enters the brain more quickly, reaching and binding to its receptors before standard morphine
43
Psychedelics (hallucinogens)
- comes from the greek words 'psyche' and 'delos', meaning "mind-manifesting"
44
LSD
hallucinogen
- is not physiologically addictive
- -> doesn't act on the mesolimbic pathway
primary effects of LSD on the brain:
- widespread activity
- enhances the effects of the serotonin system
45
two major types of receptors
- ion channels that open/close
| - tropic receptors that take slightly longer to open
46
stages of drug addiction
- binge/intoxication stage
- withdrawal/ negative affect stage
- preoccupation/ anticipation (craving) stage
