Ch 4 Neurostransmitters Flashcards
Functions of acetycholine
excitatory
- memory
- attention
Two classes of acetylcholine-containing receptors
- Muscarinic
- Nicotinic
Muscarinic receptors
mediate main cognitive effects attributed to cholinergic pathways
effects on attention, learning, short term memory
Nicotinic receptors
trigger rapid neural and neuromuscular transmission within the sympathetic and parasympathetic nervous system
Origin of acetylcholine
Basal forebrain Nucleus basalis of meynert Medial septum Nucleus of diagonal band pontomesencephalic region
Functions of norepinephrine (NE)
- excitatory attention shifting arousal modulate sleep wake cycle mood and pain
Where do norepinephrine (adrenergic neurons) form?
brainstem
released by adrenal glands
lateral tegmental area of pons and medulla
Another name for norepinephrine
stress hormone
What mood disorders are norephinephrine associated with?
depression
bipolar
anxiety, OCD
Drugs that increase NE and dopamine
ADHD meds (methylphenidate - Ritalin, Concerta), (amphetamine/dextroamphetamine - Adderall)
Drugs that targets NE alone
atomoxetine (Strattera - NE reuptake inhibitor)
Where is serotonin produced?
produced in neurons originating in the raphe nuclei located in the midline of the brainstem.
What mood disorders is serotonin associated with?
anxiety, depression, OCD, aggressive behavior, eating disorders
Drugs that are serotonin reuptake inhibitor
- post synaptic inhibition
Fluoxetine (Prozac), Sertraline (Zoloft)
Drugs that affect reuptake inhibition in the serotonergic and noradrenergic system
Venlafaxine (Effexor)
Where can dopamine be found
Substantia nigra
ventral tegmental area (VTA) - next to substantial nigra, (in the midbrain)
3 different systems of dopamine projection
mesostriatal system - parkinson’s disease
mesolimbic system - reward functions, addictive behavior (through nucleus acumbens), positive symptoms of schizophrenia if too overactive
mesocortical system - executive functions, motivation, working memory, initiation of motor activity
Is GABA inhibitory or excitatory
inhibitory
Functions of GABA
memory
anxiety/arousal
neuromodulation
Location of GABA
reticular nucleus of the thalamus
- regulate sleep and arousal
Basal Forebrain
- regulate attention shifting
- alternate between response-reinforcement
Is Glutamate excitatory or inhibitory
excitatory - the most abundant excitatory neurotransmitter in the brain
Function of gluamate
learning and memory
What happens when there is excess glutaminergic activity
excitotoxicity and cell death
ischemic cascade implicated in stroke and neurodegenerative diseases (AD, ALS)
An example of a drug that targets glutamate functions
Memantine (Namenda) - NMDA receptor antagonist, is used to treating AD
Name of Glutamate receptor
NMDA receptor
Which part of the brain is involved in akinetic mutism
Bilateral medial frontal lobe
Where is Basal Forebrain located?
a group of structures in the vicinity of ventromedial frontal lobe
anterior to caudate and putamen
Function of Basal Forebrain
major source of cholinergic input throughout the brain
What happens if Basal Forebrain is damaged
profound memory loss with confabulation
Example of disconnection theory
Alexia without agraphia
optic aphasia
impaired naming of objects in L hemisphere due to callosal disconnection of right-left hemisphere
Excitotoxicity
- pathological process by which nerve cells are damaged by excessive stimulation by NT (e.g. glutamate)
- key factor in CNS response to SCI, TBI, neurodegenerative diseases
