Neurophysiology-- PNS efferent (Unit 2)

ANS control centers

hypothalamus, pons, medulla (brain stem)

Where are cell bodies of these efferent motor neurons located in spinal cord

somatic (skeletal muscle)

autonomic (non-voluntary)

anterior horn

anterior lateral horn (anterolateral)

where are cell bodies of sensory neurons located in spinal cord

dorsal root ganglion

where are cell bodies of these interneroun cell bodies located in spinal cord

somatic (voluntary)

visceral (in this scenario the word means non-voluntary, automatic)

posterior horn

posteriorlateral horn

REMEMBER SENSORY GOES ---- SPINAL CORD, AND MOTOR GOES ---- SPINAL CORD

sensory = behind

motor= front

visceral neuron vs autonomic neuron

visceral sensory neuron and autonomic motor neuron are both non-voluntary neurons.

Somatic neurons -- synapse with ganglion/cell bodies. goes....

DONT.... they go straight to skeletal muscle

visceral effectors

smooth muscle, cardiac muscle, glands, adipocytes

ANS synapse with

other bodies in ganglion

preganglionic bodies originate where

anterolateral horn

for sympathetic neurons... postganglionic neurons cell bodies are where

sympathetic chain ganglion or collateral ganglion, OR adrenal medulla

thoracolumbar

sympathetic division of ANS (thoracic and lumbar regions of spinal cord)

craniosacral

parasympathetic division of ANS (cranial and sacral regions of spinal cord)

for parasympathetic neurons... postganglionic neurons cell bodies are where

either sacral ganglion (when pre-ganglionic neuron comes from Sacral area), or terminal ganglia (when pre-ganglionic neuron comes from cranial), OR BYPASS terminal ganglia to go through vagus nerve

vagus nerve innervated

heart, lungs, and guts

where do post-ganglionic collateral sympathetic nerves go innervate

viscera= guts

sympathetic chain ganglia is important innervation for

heart, lungs, guts

where is epinephrine secreted

adrenal medulla (on kidney)

catecholamines

dopamine, norepinephrine, epinephrine

norepinephrine vs epinephrine

norepinephrine is released in synapses, epinephrin is only secreted from adrenal medulla

the adrenal medulla is innervated by ---- cells

chromaffin

chromatin cell is innervated by

pre-ganglionic sympathetic neurons

PNMT located where, and does what

adrenal medulla, and catalyzes the formation of epinephrine from norepinephrine

Rn

nicotinic receptor

preganglionic cells secrete

ACh NO MATTER THE PATHWAY

PNS post ganglionic secretes ----

ACh

SNS post ganglionic neurons secrete ---

Norepinephrine

SNS chromatin cell secretes

EPI/NE

NEJ

neuroeffector junctions in smooth muscle

smooth muscle have what kind of NEJ

varicosities (bulges) instead of terminal knobs in smooth muscle

NMJ

motor end plate in SKELETAL MUSCLE

MAO

monoamine oxidase. degrades NE

ANS controls the activity of

cardiac muscle, smooth muscle, glands, and adipose

exceptions to dual innervation of ANS

sympathetic NS SOLELY innervates vascular smooth muscle( blood vessels (except in the heart and genitals)), sweat glands, and adipose.

noreadrenergic is same as

norepinephrine.. just means NOREPI is secreted in adrenergic receptors.

adrenergic synapses release what neurotransmitter, to what receptors (sympathetic)

catecholamines, to Alpha and beta receptors.

cholinergic synapses release what neurotransmitter, to what receptors (parasympathetic)

ACh, to muscarinic (parasympathetic) and nicotinic receptors (somatic).

prevertebral ganglia

another way to say collateral ganglia.

alpha 1 adrenergic receptors agonist

constriction of smooth muscle (vasoconstriction), bronchial smooth muscle (bronchoconstricton), and increased sweat gland secretion.

antagonists of alpha 1 adrenergic receptors

decrease blood pressure by blocking alpha 1 so norepinephrine and epic can't bind to receptor. vasodilation

prazosin (MINIPRESS)

ALPHA 1 blocker

alpha 2 adrenergic receptors

decrease GI tract activity

beta 1 adrenergic receptor agonist

increase strength of heart contraction (contractility), and increase heart rate (pacemaker increases).

beta 1 adregeric receptor antagonist

blocks B1 adrenergic receptor so NE and E can't bind. decreases blood pressure.

metoprolol LOPRESSOR

more commonly used to decrease blood pressure than prazosin. but this decreases blood pressure directly on heart muscle and pacemaker cells.

beta 2 adrenergic receptor agonist

bronchial smooth muscle relaxation (bronchodilation), and increase airway diameter

is there more beta 2 or alpha 1 receptors on bronchial smooth muscle

beta 2 because is dilates the lungs. and alpha constricts. but we know sympathetic overall dilates lungs

SABA-- albuterol (VENTOLIN)

short acting beta agonist.... albuterol is used for person with asthma to open airways on bronchial smooth muscle.

IF

voltage gated Na+ channel. opens when cell repolarizes or cAMP internally binds to open channel. WIERD

auto rhythmic cardiomyocyte

pacemaker cite, Beta 1 receptors, internal gated by cAMP and volatage gated Na+ channels. activation leads to increased heart rate (sympathetic)

contractile cardiomyocytes

Beta 1 receptors (and beta 2 but more beta 1), Gs G-protein, cells in smooth muscle contracts when calcium enters cell. Increases contractility

what activates Beta 1 receptors in cardiac muscle and pace maker

catecholamines, isoproterenol, sympathomimetics, indirect actions

indirect actions to increase heart rate

increase activity in CNS so activity sent from brain to increase heart rate. these are from caffein and Guarana (like an expresso bean but more caffeine)

sympathomimetics

mimic catecholamines.. ephedra- ma Huang (FDA banned cause ppl use as pre workout), synephrine- bitter orange (causes heart attacks do to vasoconstriction and increase heart rate)

synephrine also bind to

all other alpha and beta cells. cause mimic catecholamines

how sympathetic innervation of blood vessels doesn't require parasympathetic

because the blood vessels are always slightly constricted (sympathetic tone) at basal state, so increasing alpha 1 sympathetic innervation will constrict blood vessel, and decreasing alpha 1 activation will dilate blood vessel.

phenylephrine, and pseudoephedrine (SUDAFED)

increase vascular constriction of blood vessels. used to help flu like symptoms to stop snotting.

important note about drugs

dont have eyes so like for Sudafed your heart rate will increase

Sudafed can be made into

BAD DRUGS so pharmacies tract how much you buy

vascular smooth muscle cell is activated by

sympathetic innervation, alpha 1 adrenergic cells, Gq coupled g-proteins.

anaphylaxis

sever allergic response, bronco constriction (can't breath) and vasodilation (light headed)

treatment of anaphylaxis

epiPen. releases episodes to bind to all alpha and beta receptors. broncodillation, vasoconstriction.

receptor determine

response

bronchiole smooth muscle cell has what type of receptors and type of protein

mostly beta 2, and Gs g-proteins.

SABAs, albuterol (VENTOLIN)

used on beta 2 adrenergic receptors to basodilate lungs.

muscarinic receptors

M 1, 2, 3, 4, 5

M1

increases salivary gland and GI tract gland secretion (parasympathetic)

M2

decreases heart rate, bronchial smooth muscle constriction

M2 muscarinic antagonists do what

increase heart rate by through pacemaker or bronchodilation.

atropine

muscarinic antagonist. atropine

blocks parasympathetic tone so increases heart rate.(used when poisened or before giving anesthetic)

can also block M3 to allow pupil to dilate (used when go to doctor to look in eye)

parasympathetic tone on

pacemaker. constant ACh on pacemaker to keep heart rate down

SAMAs- ipratropium (ATROVENT)

short acting metabolic antagonist. causes bronchodilation

M3 muscarinic agonist

parasympathetic-- increase salivary gland and GI tract gland secretion. (overlap with M1)

bronchoconstriction (like M2)

pupillary muscle contraction (miosis) and ciliary body contraction (lens accommodation)

M4 and M5

parasympathetic, effect CNS

Autorhythmic cardiomyocyte (parasympathetic)

vagus nerve constant drips ACh to decrease heart rate on M2 receptors. these receptors activate Gi g-proteins.

poisoning treatment

AtroPen- used to block M2 receptors, atropine in this, increases heart rate.

parasympathetic innervation of genitals

vasodilate to erect peep. this increases blood flow to 3 spaces in peepee.

viagra and Cialis

cyclic GMP PDE inhibits so increases cGMP to relax smooth muscle and increase blood flow

what receptor type on genitals

m3

arterial baroreflex

monitor internal environment of the body. pushing of blood activated mechanism-receptors in barorectors. this increases AP to brain step.

baroreflex detects HIGH Bp sooo

increases vagus nerve (increase parasympathetic),

low sympathetic-- lowers NOREPI on beta 1 pacemaker cells, and decrease sympathetic innervation to blood vessels to vasodilate.

Arterial chemoreflex (ACR)

in coratid and aortic arch and responds to chemicals BUT MOSTLY oxygen changes

the enteric nervous system is activated by

local stimulus like a stretch, ph or osmolarity change, or FEED FORWARD STIMULUS (so see or smell food)

4 layers of GI

muscosa, submuscosa, muscularis, serosA

Mucosa

contains mucous epithelium and lamina propria in GI

mucous epithelium

inner layer of mucosa in GI

lamina propria of mucosa

loose connective tissue, location of all glands in GI

submuscosa

denser more blood vessels. controls glandular secretions. in GI

ENS is innervated by

myenteric plexus and submucosal plexus in GI

muscularis

two layers of GI. circular and longitudinal muscle. between these two is the myenteric plexus

myenteric plexus is responsible for

motility. so contraction of muscle

submucosal plexus is responsible for

glandular secretions. its in submucosa.

serosa of GI

outer layer of GI with 2 layers of peritoneum. two visceral layers= mesentery. so blood vessels and nerve fibers in these.

Auerbachs of Small I

myenteric plexus

Meissners of Small I

submucosal plexus

vagus sending signals to Enteric NS is

feed forward

somatic nervous system involves--- while ANS doesnt

frontal lobe (voluntary)

skeletal muscle cells 1st orginate where

in frontal lobe

somatic motor neurons cell bodies found where

anterior horn

somatic neuron axon is also called

alpha motor neuron. cause doesnt have post or pre ganglionic neurons.