Physio final lecture 1-3 Flashcards
_______ % total resting oxygen used by brain
20%
_______________% of total blood flow goes to the brain
15-20%
___________% of glucose metabolism used by brain
60%
energy division of brain use
~25% maintaining neurons and glial cells
~75% electrical signaling across the brains circuits
planned and purposeful neuronal cell death; removal of damaged or unneeded neurons
apoptosis
unplanned and uncontrolled neuronal cell death
necrosis
a natural process that occurs in the brain when the brain eliminates extra synapses
synaptic pruning
the structures in the brain that allow the neurons to transmit an electrical or chemical signal to another neuron
synpases
pruning = ….
efficiency
schizophrenia is correlated with …
low synapses (high pruning)
Autism is correlated with …
high synapses (low pruning)
Frontal lobe fx
executive fx (emotion regulation, planning, reasoning, inhibitory control)
personality
dominant hemisphere = social conduct
*phineas Gage
Prefrontal cortex
seat of planning and strategizing
ventromedial PFC
empathy, guilt
parietal lobe
integrating sensory info including…
touch
temp
pressure
pain
Occipital lobe
visual processing (depth distance location)
contains the primary visual cortex
temporal lobe
processing sensory information particularly important for hearing, recognizing language and forming memories
contains the primary auditory cortex
basal ganglia
part of the limbic system
controls: motor control, motor learning, executive functioning and behaviors, and emotions
substantia Nigra
produces dopamine (high concentration in the basal ganglia)
dopamine modulate the BGs fxing
dopamine dysfunction
movement disorders such as Parkinson’s, dystonia, chorea and tics
suppression of motor function =
decreased purposeful movement
limbic system
emotions, motivation, learning, memory
Nervous system
peripheral
central
central NS
brain
spinal cord
Peripheral NS
Autonomic NS
Somatic NS
Autonomic NS
sympathetic NS
Parasympathetic NS
Somatic nervous system
made up of spinal nerves and cranial nerves
spinal nerves
mixed nerves that carry sensory info INTO and motor commands OUT of the spinal cord
Cranial nerves
nerve fibers that carry info into and out of brain stem
sympathetic division of autonomic NS
“fight flight freeze fawn”
controls fx that accompany arousal and expenditure of energy
coordinates responses to a stressor
“thoracolumbar system”
dilated pupils, inhibits salivation, accelerates heart rate
parasympathetic division of autonomic NS
“rest and digest”
involved in increases in body’s supply of stored energy coordinates rest and relax response after the body has been stressed
“craniosacral system”
vagus nerve responsible for the calming following a stressful situation
constricts pupil, stimulates salivation, slows heart rate
______ L /min blood pumped every ________
5
minute
entire volume of blood supply circulates every _____
minute
Intravenous administration
fastest and most dangerous
30-60 seconds
right into blood stream
intraperitoneal administration
into stomach
intramuscular administration
into muscle
subcutaneous administration
into fat
intracerebral administration
bypasses the BBB
into brain
intracerebroventricular administration
into ventricular system to reach CSF
bypasses BBB
oral administrations
sublingual - under tongue
most common
“first pass” metabolism
intrarectal administration
into the rectum
inhalation administration
into the lungs
insufflation administration
into the nasal passages
topical administration
onto skin
distribution
entry of drugs into the brain
drugs exert effects only at their sites of action
mostly on or in cells of the CNS
most important factor in determining the rate of distribution …. (and why)
lipid solubility
lipid soluble materials pass through BBB the most rapidly
heroin > morphine
primary organ of excretion
kidney
organ that plays active role in enzymatic deactivation
Liver
(and brain but to a smaller extent)
Therapeutic index
a commonly used margin of safety
ED50 and TD50 provide a ratio which - therapeutic index (TD50/ED50)
quantitative measurement of the relative safety of a drug
therapeutic index: effective dose 50
(ED50) the dose that produces the desired effects in 50% of individuals
therapeutic index: toxic dose 50
(TD50) the dose that produces toxic effects in 50% of individuals
Ideal therapeutic index
> 10
drugs with low TI
litium
carbamazepine
valproic acid
clozapine
tricyclic antidepressents
agonist
a molecule that binds to the receptor to stimulate a response = increased postsynaptic effects
ex) addictive drugs (heroin, morphine) = stimulation = high
antagonists
a molecule that by binding to a receptor blocks or inhibits the response = decreased postsynaptic effects
botulin poison causes paralysis by blocking the release of acetylcholine = wrinkles cannot form d/t the area being paralyzed
