Pathophysiology- Autonomic Nervous System-Dr. Luthin

Adipose

"Fat" portion of ANU

Sympathetic Nervous System motto

"Fight or Flight"

When homeostasis shifts in regards to ANS

"Moving dimmer on light switch" "TeeterTotter out of balance" Depending on signal Para or Sym will dominant

Parasympathetic Nervous System motto

"Rest and Digest"

Central Nervous system contains?

(CNS) Brain and spinal cord

In sweat glands what receptor does NE activate?

(α1) adrenergic receptor Localized sweating (i.e. palms of hands)

Where are Alpha-2 Receptors?

*Beta cells of pancreas ↓ insulin secretion *Smooth muscle and secretory cells of many digestive organs ↓ GI motility & secretions *Blood platelets ↑ Clotting (exception!)

are Beta-1 Receptors?

*Cardiac muscle ↑ heart rate ↑ force of contraction *Adipose tissue ↑ lipolysis *Kidney cells that make the hormone renin ↑ secretion renin (↑BP) *Posterior pituitary ↑ secretion ADH

Where are Beta-2 Receptors?

*Smooth muscle of "special" blood vessels serving: Heart (coronary arteries) Skeletal muscle Liver *Smooth muscle of bronchioles: (Bronchodilation!) *Smooth muscle of digestive organs (↓ motility): (Most abdominal viscera) *Alpha cells of pancreas: (increase Secretion of glucagon)

Sympathetic System Primary NTs; Target organ receptors

, Norepinephrine (NE), Epinephrine (Epi.); α &β - receptors

Para ratio of POST to PRE ganglionic neurons

1:1 Fine tuned reaction., small adjustment relaxation key

Sym ratio of POST to PRE ganglionic neurons

20:1 Amplified LARGE reaction

_______________% of all PNS fibers are from one cranial nerve, what is it?

75-80 Vagus

Neurons

A nerve cell; the basic building block of the nervous system.

Which of the following is innervated by postganglionic fibers arising from the cervical ganglia? A) The eyes. B) The digestive system. C) The urinary system. D) The reproductive system.

A) The eyes.

A ganglion is defined as a collection of cell bodies located within the peripheral nervous system. A) True B) False

A) True

Adrenergic stimulation of target cells by epinephrine (usually from the adrenal medulla) and by norepinephrine (from sympathetic nerve endings) can produce both excitatory and inhibitory effects on the target cell. A) True B) False

A) True

Both nicotinic and muscarinic subtypes of receptors respond to acetylcholine as a neurotransmitter. A) True B) False

A) True

Cardiac muscle cells and many smooth muscle cells can contract rhythmically in the absence of autonomic stimulation. A) True B) False

A) True

In the gastrointestinal tract, activation of parasympathetic neurons increases the intensity of intestinal smooth muscle contractions and intestinal secretions. A) True B) False

A) True

Most visceral organs receive dual innervation--stimulation from both sympathetic and parasympathetic nerve fibers. A) True B) False

A) True

Organs that lack dual innervation only receive sympathetic innervation. A) True B) False

A) True

Sympathetic stimulation of the pacemaker region of the heart increases the heart rate. A) True B) False

A) True

The drug that mimics the action of a neurotransmitter is said to be an agonist of that neurotransmitter. A) True B) False

A) True

The preganglionic sympathetic and parasympathetic nerves both release acetylcholine. A) True B) False

A) True

The term viscera refers to the organs located within the body cavities. A) True B) False

A) True

The vagus nerve is a mixed nerve, containing both sensory and motor fibers. A) True B) False

A) True

There are certain postganglionic autonomic axons that produce their effects through mechanisms that do not involve either norepinephrine (adrenergic) or acetylcholine (cholinergic) neurotransmitters. A) True B) False

A) True

Those sympathetic postganglionic neurons activating blood vessels in skeletal muscle and in sweat glands are unique in their release of acetylcholine instead of the norepinephrine. A) True B) False

A) True

Unlike somatic motor neurons that always cause stimulation of skeletal muscle, some autonomic nerves release neurotransmitters that inhibit the activity of their effectors. A) True B) False

A) True

Unlike the somatic nervous system which has one synapse in the periphery, the autonomic nervous system has two peripheral synapses. A) True B) False

A) True

When the parasympathetic system is stimulated, what neurotransmitter is released at the effector organ? A) acetylcholine B) norepinephrine C) epinephrine D) dopamine

A) acetylcholine

Which of the following target tissues is innervated by only neurons from the sympathetic nervous system? A) adrenal medulla B) lacrimal glands C) bronchioles D) iris of the eye

A) adrenal medulla

The separate effects of sympathetic and parasympathetic innervation of the heart can best be described as A) antagonistic. B) complementary. C) cooperative.

A) antagonistic.

The brain area that most directly controls the activity of the autonomic nervous system, is the A) medulla oblongata. B) pituitary gland. C) cerebellum. D) hypothalamus.

A) medulla oblongata.

Which of the following target tissues receive acetylcholine when the sympathetic division is stimulated? A) sweat glands B) salivary glands C) smooth muscle of the GI tract D) heart

A) sweat glands

If cocaine blocks the reuptake of catecholamines it would be considered a A) sympathetic agonist. B) sympathetic antagonist. C) sympathetic neurotransmitter. D) parasympathetic agonist.

A) sympathetic agonist.

All preganglionic nerve fibers of Para and Sym release what NT?

ACh

NT of nicotinic receptors

ACh

How do you treat Alzheimer's symptoms?

AChE inhibitor (antagonist)

Accommodation (eye)

ACh→M₃→innervates ciliary muscle= lens focus

Two ways M₃ receptors can affect eye

Accomodation→ ACh → M₃ on ciliary muscles contract→lens focused for close vision not farsighted

Parasympathetic System Primary NT; Target organ receptor

Acetylcholine (ACh); Muscarinic

SNS pre-ganglionic neuron has what sort of potential?

Action

Benefit of Varicosities

Action Potentials that reach the neuroeffector - Ca²+ release, and NT floods out of swellings Overall NT release is more widespread than at the typical junction.

antagonist

Acts against/ Blocks effect of natural NT @ receptor site

agonist

Acts in similar manner "mimics" natural NT or hormone at receptor site

Leptin

Adipostat, a fat hormone, regulates fat in fat cell.

Modified sympathetic ganglion cells are located directly in the medulla of the _________________gland.

Adrenal

Specialized SNS gland above kidneys.

Adrenal Gland

Longest path of SNS

Adrenal Medulla

INFO @ ORGAN-> CNS

Afferent

Sensory nerves carry.

Afferent signals

The neurotransmitter, norepinephrine binds to two classes of receptor proteins,_____________________________ and______________________ , that, in turn, have two subtypes.

Alpha Beta

Alpha 1 receptors do what?

Alpha 1 receptors do what? stimulate GPCR (activate phospholipase C) for contraction and secretion in most sympathetic target tissues (Ca constricts/relaxes GI blood vessels)

An increase in sympathetic nerve stimulation to blood vessels causes vasoconstriction, whereas vasodilation of blood vessels is caused by an increase in parasympathetic nerve stimulation. A) True B) False

B) False

Blushing, pallor, fainting, breaking out in a cold sweat, a racing heartbeat, and "butterflies in the stomach," are only some of the many visceral reactions that accompany emotional activation of the cerebellum region of the brain. A) True B) False

B) False

Both sympathetic and parasympathetic neurons have preganglionic cell bodies located inside the PNS and postganglionic cell bodies located outside the CNS. A) True B) False

B) False

Cholinergic receptors located on the membrane of target cells are divided into alpha and beta subtypes. A) True B) False

B) False

During emergency situations, activation of the sympathetic nervous system ("flight-or-fight") will stimulate contraction of the circular muscles of the eye and the pupils will constrict. A) True B) False

B) False

Ganglia are an integral part of the somatic motor pathway. A) True B) False

B) False

Nicotinic receptors are G-coupled receptors and muscarinic receptors are ligand-gated ion channels. A) True B) False

B) False

Postganglionic sympathetic and parasympathetic neurons usually release acetylcholine. A) True B) False

B) False

Stimulation of b-adrenergic receptors almost always causes smooth muscle contraction, resulting in constriction of small blood vessels (vasoconstriction). A) True B) False

B) False

Sympathetic nerves to the visceral organs consist of preganglionic fibers, whereas parasympathetic nerves to these organs contain postganglionic fibers. A) True B) False

B) False

The effects at the synapses of somatic motor neurons and preganglionic autonomic neurons can be both excitatory and inhibitory. A) True B) False

B) False

The response of a target cell when norepinephrine binds to β2 receptors results in a rise in intracellular calcium (Ca2+) concentration that serves as a "second messenger" rather than cAMP. A) True B) False

B) False

The two subtypes of alpha receptors produce their effects by stimulating increases in cyclic AMP (cAMP) production within the target cells. A) True B) False

B) False

Which neuron does releases a catecholamine as a neurotransmitter? A) Preganglionic sympathetic fibers B) Postganglionic sympathetic fibers C) Preganglionic parasympathetic fibers D) Postganglionic parasympathetic fibers

B) Postganglionic sympathetic fibers

Which of the following statements does not describe denervation hypersensitivity? A) Autonomic target tissues become more sensitive than normal to stimulating agents. B) Skeletal muscle effectors enter a state of paralysis and undergo atrophy. C) Severing (cutting) autonomic motor neurons may stimulate denervation hypersensitivity. D) One example is restoring the secretion of acid from the stomach following vagotomy (severing the vagus nerve).

B) Skeletal muscle effectors enter a state of paralysis and undergo atrophy.

Which statement regarding autonomic parasympathetic neurons is true? A) They are usually activated as a single unit (mass activation). B) They emerge from the brain and sacral regions. C) They form white rami communicantes fibers. D) They may have ganglia located along the spinal cord.

B) They emerge from the brain and sacral regions.

Which of the following statements is true for preganglionic neurons of the Sympathetic Nervous System? A) They are relatively long. B) They exit from the T2-L2 region of the spinal cord. C) They release epinephrine. D) They synapse at the effector organ.

B) They exit from the T2-L2 region of the spinal cord.

Which of the following statements about parasympathetic neurons is true? A) The nerve fibers are contained in spinal nerves. B) They synapse in terminal ganglia, either next to or within the organs innervated. C) They originate in thoracic and lumbar regions of the spinal cord. D) Postganglionic fibers are usually longer than those of sympathetic neurons.

B) They synapse in terminal ganglia, either next to or within the organs innervated.

All of the following molecules are considered "nonadrenergic noncholinergic" neurotransmitters produced by postganglionic autonomic axons, except A) adenosine triphosphate. B) acetylcholine. C) vasoactive intestinal peptide. D) nitric oxide

B) acetylcholine.

Which of the following target tissues does not receive dual innervation? A) lung B) adrenal medulla C) heart D) small intestine

B) adrenal medulla

The effects of sympathetic and parasympathetic stimulation of the salivary glands, producing a thicker, more viscous saliva, are called A) antagonistic. B) complementary. C) cooperative.

B) complementary.

The drug muscarine, derived form some poisonous mushrooms stimulates all of the following cholinergic receptors, except those receptors in the A) heart. B) neuromuscular junction of skeletal muscle fibers. C) digestive system. D) most target organs of postganglionic parasympathetic nerve fibers.

B) neuromuscular junction of skeletal muscle fibers.

In general, parasympathetic activation will produce effects that are __________ to those produced by activation of sympathetic neurons. A) similar, agonistic B) opposite, antagonistic C) complimentary D) synergistic

B) opposite, antagonistic

Catecholamines are derived from A) acetylcholine. B) tyrosine. C) tryptophan. D) epinephrine.

B) tyrosine.

The Nervous System is Divided into

Central Nervous System and Peripheral Nervous System

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons

Autonomic Control of Eye- Pupils

Circular Muscle (contracts) = miosis Radial Muscle (contracts) = mydriasis

Parasympathetic Overview

Constrict - pupils, airways, bladder Stimulates- stomach GI tract, gallbladder, saliva Inhibits - Release of insulin& pancreatic enzymes Promotes - erection sex organs ↓-heart beat

Autonomic Summary of function

Control Metabolism Visceral Function-movement in internal organs and secretions

Adrenal Cortex produces?

Cortisol Aldosterone Adrenal Androgens

Neurons exit spinal cord at __________________&__________________ in the parasympathetic system

Cranial (Top of spinal cord); Sacral(Bottom)

Parasympathetic Location of spinal cord exit

Craniosacral

The "fight or flight" response is the term used to describe activation of the ____. A) ANS B) CNS C) Parasympathetic D) Sympathetic

D) Sympathetic

Which of the following is NOT a result of parasympathetic activation? A) increased lacrimation B) increased urination C) bronchoconstriction D) increased sweating E) increased salivation

D) increased sweating (general sweating sym response)

Somatic motor neurons have cell bodies located ____ the CNS that project axons only to ____; and are usually under ____ control. A) outside; skeletal muscle; involuntary B) inside; the viscera; voluntary C) inside; the viscera; involuntary D) inside; skeletal muscle; voluntary

D) inside; skeletal muscle; voluntary

The very long cranial nerve that originates from nuclei in the medulla oblongata and projects preganglionic fibers through the neck to the thoracic and abdominal cavities, is the _____ nerve. A) optic (II) B) oculomotor (III) C) facial (VII) D) vagus (X)

D) vagus (X)

"High Vagal Tone" implies

High PNS activity, general tone is the balance of the rate of nerve firings from vagus nerve

Adipostats

Hormones that increase with body fat, tell brain levels of fat to help maintain set point? Thin person has less adipostat hormones, fatty has more

Why do we need both NE and Epinephrine?

NE- leaks into tissues does not dilute or travel, blood vessels constract Epi- Diluted into bloodstream to target organs, blood vessels binds to β2-receptors = helps organs relax

Can somatic motor neurons be inhibitory?

NO; excitatory only for muscle contraction

Efferent Nerons

Nerves that carry impulses away from the brain and spinal cord to the muscles and glands. Also called motor neurons.

Nicotinic Receptors

Neural neuromuscular

Varicosities

Neuroeffector Junction (release NT at target organ) release at swellings across axon. Propagated by K+ and Na+ Channels & Voltage-gated Ca²+

Afferent Neurons

Neurons that transmit messages from sense organs to the central nervous system.

Neuromuscular

Nicotinic Receptor Nm ↑ Muscular

Neural

Nicotinic Receptor: Ng ↑ ganglia

SNS function?

Signal is ALWAYS - Excitatory

Somatic Target tissue

Skeletal Muscle

Postganglionic sympathetic fibers that innervate the blood vessels of ______________________muscle and those that innervate ___________________________glands are cholinergic.

Skeletal muscle; sweat

Autonomic Target tissue

Smooth & Cardiac Muscle Some exocrine and endocrine glands some Adipose Tissue

Skeletal Muscle Contraction - system

Somatic Nervous System

Compare number of nerves in the efferent pathway.

Somatic-1 Autonomic-2

SNS voluntary or involuntary?

Voluntary

SNS- Involuntary or Voluntary

Voluntary

The only neurotransmitter released by nerves in the parasympathetic nervous system is ______________________ and such fibers are said to be_______________________________

acetylcholine cholinergic

ANS "tone"

activity of Vagus nerve

Epinephrine "aka"

adrenaline

Peripheral Nervous Systems contains?

afferent "sensory" and efferent neurons *Everything except CNS

Muscarinic Cholinergic receptors

agonist receptors that are G protein coupled receptors

Nicotinic cholinergic receptors

agonistic receptors found in skeletal muscle, in CNS, and autonomic division of the PNS

What are the most common sympathetic receptors and to what do they respond most strongly?

alpha receptors; NE

A drug like propranolol that blocks the action of a neurotransmitter in the synapse is said to be a(n) ____________________________ of the neurotransmitter.

antagonist

Inhibitor "aka"

antagonist

The opposing effects of sympathetic and parasympathetic stimulation on the pupil of the eye represents an example of ________________________________ effects.

antagonistic

There are two major categories of motor neurons: somatic and_____________________________

autonomic

Treat high bp and tachycardia.

b1 antagonist/beta blocker

Cholinergic Receptors

bind ACh

What can help relieve urinary symptoms of prostatic enlargement?

block alpha 1 adrenergic receptors on bladder/prostate

If two ACh NTs bind to Na+ channel, what occurs in the postganglia

cell depolarization (more positive)

Muscarinic and nicotinic receptors are what receptor type?

cholinergic

Sym ganglia location

close to cord

Somatic motor neurons branch where?

close to target muscle

Para ganglia location

close to target organ

Treat nasal congestion.

constrict blood vessels a1 agonist

The stimulation of α-adrenergic receptors consistently causes __________________________of smooth muscles, whereas the ß-adrenergic effects are more complex.

contraction

Treat allergic reaction.

convert vasodilation to vasoconstriction EP or antihistamine

Treat asthma.

dilate bronchi b2 agonist

(2 words) means that an organ can be stimulated by both sympathetic and parasympathetic neurons.

dual innervation

Axons of autonomic nerves are always motor or ___________________ , with the cell body located in the gray matter of the_____________________ or the spinal cord.

efferent brain

The three effectors found at the end of all autonomic neurons are cardiac muscle (the heart), smooth muscle (visceral organs), and____________________________________.

glands (endocrine, exocrine)

The two most important regions of the brain directly responsible for the control of autonomic nervous system activity are the ___________________________and the limbic system.

hypothalmus

Effect of M₃ antagonist?

inability to sweat (clinical application: boys in desert that ingested Jimsonweed, and died of hyperthermia)

Sweat Glands the exception, not the rule

innervated by sympathetic neurons, Depending on location of nerve release: -ACh(sympathetic cholinergic) OR -NE (sympathetic noradrenergic).

Vagus nerve controls which internal organs, through what nerve fibers?

lungs, liver, pancreas, stomach, spleen, small intestine, proximal 2/3 of colon parasympathetic

The adrenal medulla is often described as what?

modified sympathetic ganglion

Innervation

nerve sends signal to target organ=organ response

Mixed nerve

nerve that carry both afferent and efferent signals

Nervous Syste,

network of billions or trillions of nerve cells linked together in a highly organized manner to form the rapid control system of the body

The drug curare is used clinically to relax skeletal muscles because this drug specifically blocks the__________________________type of cholinergic receptors present in the neuromuscular junction.

nicotinic

Cholinergic receptors are classified as either_____________________________ or ________________________________.

nicotinic Muscarinic

The somatic motor pathway uses what type of receptors?

nicotinic cholinergic receptors

Norepinephrine "aka"

noradrenaline

"Fight or flight" results from the release of ___________________ as the neurotransmitter from postganglionic sympathetic neurons and ______________________________ from the adrenal medulla.

norepinephrine epinephrine

Many cranial nerves are preganglionic ___________________neurons with short postganglionic neurons because the ganglia are located close to or within the target cells.

parasympathetic

What do autonomic neurons innervate?

smooth muscle, cardiac muscle, glands, adipose

Sympathetic yet cholinergic response

sweat glands

erector pili (goosebumps)

sym =contracts, erects para= none (not innervated)

salivary glands α-2 and β-2

sym =mucus, enzymes para= watery secretion

pupil α-1 M₃

sym =α-1 dilates (mydriasis) para =M₃ constricts (miosis)

exocrine pancreas a2

sym decreases enzyme& insulin secretion, para increases enzyme& insulin secretion,

sex organs a1

sym ejaculation para erection

Heart β-1

sym increases rate, force of contraction para decreases rate

kidney b1

sym increases renin secretion

adipose tissue b3

sym lypolysis (fat burning, brown fat)

adrenal medulla no adrenergic receptors

sym secretes catecholamines

urinary bladder b2

sym urinary retention para urine release

blood vessels α1 and β2

sym= constricts and dilates para = no direct effect, innervated @ organ sites = dilation

lymphoid tissue a and b2

sym= inhibits it

Preganglionic sympathetic neurons emerge from the________________________ levels of the spinal cord, whereas preganglionic parasympathetic fibers originate in the____________________________ and _______________________levels of the spinal cord

sym= thoracolumbar para= brain; sacral

digestive tract α1 and α2

sym=decreases motility and secretion para= increases motility and secretion

Body temperature regulation (thermogenesis) is accomplished entirely by the action of neurons from the___________________________branch of the autonomic nervous system.

sympathetic

Para Length of PRE to POST ganglionic neurons

Pre-long Post-short

Can both branches of ANS be activated simultaneously?

Yes, like a dimmer switch usually, but both can be active.

Is the vagus nerve a "mixed" function nerve?

Yes, signal goes both ways (afferent and efferent directions)

Splanchnic Nerves

Innervate Organs

ANS - Involuntary or Voluntary

Involuntary

ANS voluntary or involuntary?

Involuntary

Compare speed of Autonomic ganglion response to that of the target tissue

Autonomic Ganglion →nerve to nerve response- QUICK Nerve- to Tissue slower

ANS

Autonomic Nervous System

In sweat glands what receptor does ACh activate?

M₃ (muscarinic) Generalized sweating (possibly profuse)

Acetylcholinesterase

Breaks down ACh into choline and acetyl coA

⊥Targets of the autonomic nervous system include all of the following except A) cardiac muscle. B) exocrine glands. C) skeletal muscle. D) endocrine glands.

C) Skeletal Muscle

The effects of sympathetic and parasympathetic innervation on the urinary and reproductive systems, causing the male erection and ejaculation for example, are called A) antagonistic. B) complementary. C) cooperative.

C) cooperative.

The hypothalamus does not contain a control center for the homeostatic regulation of A) body temperature. B) various emotional states. C) urinary bladder reflexes. D) eating.

C) urinary bladder reflexes.

Sympathetic Pathway

CNS Axon(pre-ganglionic fiber (short, near CNS) Autonomic Ganglion -release ACh Nicotinic Receptor on post-synaptic ganglion (LONG) 2nd synapse- release NE α - receptor, -innervates organ

Adrenal Sympathetic Pathway

CNS Axon- Pre-ganglionic sympathetic neuron Release ACh in Adrenal Medulla modified post-ganglionic sympathetic neuron Release Epi. into Blood Enter Blood vessel - rides to target organ-β₁-receptor and β₂-receptors

Parasympathetic Pathway

CNS- Axon (pre-ganglionic fiber)-(LONG) Autonomic Ganglion (synapse)- -release ACh Nicotinic Receptor on Post-synaptic Ganglion (short near target organ) 2nd synapse -release ACh Muscarnic Receptors - innervates organ

Somatic Nervous Pathway

CNS-Axon- Somatic Nerve Fiber-Nicotinic Receptor on Target muscle. innervates SKELETAL MUSCLE Receptor close to target tissue.

Inhibitory function

Calms brains, creates balance. Balance mood. Easily Depleted

Primary Tissues in ANS

Cardiac Muscle Smooth Muscle Glands- Endocrine and Exocrine Adipose

Info @ CNS-> ORGANs

Efferent

Motor nerves carry

Efferent signals

SNS post-ganglionic neuron has what sort of potential

Electric

Effect of M₃ agonist?

Excessive sweating, profusely

ANS function?

Excitatory and Inhibitory

Glands for the GI tract are?

Exocrine glands, the "tube" is technically any secretions into tube just travels through the body to the OUTSIDE.

GI glands are Endocrine glands.

False, they are EXOcrine glands- secretions go OUTSIDE.

Smooth Muscle Tissue

GI Tract LUNGS Eyes (diameter of pupils- miosis or mydriasis) Uterine Urinary Tract Blood Vessels Bladder

Are SNS signals specific or general innervations?

General ration of Post to Pre ganglia 20:1 Amplified response

Are channel-mediated events relatively fast or slow, give example of such event

N-N, FAST Depolarization

NE and ACh are synthesized from what?

NE = tyrosine ACh = acetyl CoA + choline

Endocrine Glands

In the bloodstream

Somatic Nervous Sytem

Info. to and from skin and skeletal muscle

Nicotinic receptors have what kind of channels

Ligand-gated Na⁺

The ____________________________ receptors that bind acetylcholine are similar to adrenergic receptors structurally in that both receptor types are G-coupled receptors.

Muscarinic

INDIRECT effect and typically a longer lasting effect. This effect can be either excitatory or inhibitory

Muscarinic Receptors

Exocrine Glands

Outside the body

miosis

PARA-ACh→M₃

Activated system with body @ REST

Parasympathetic

Generally which branch of ANS is predominants?

Parasympathetic System

ANS divided into...

Parasympathetic and Sympathetic

Somatic Summary of function

Posture and Movement

Sym Length of PRE to POST ganglionic neurons

Pre- Short Post-long

Somatic V. Autonomic Neurotransmitter/receptor at neuron-target synapse

S- ACh/Nicotinic A- ACh/Nicotinic ; NE/α- or β-adrenergic

Somatic V. Autonomic Neurotransmitter released from

S- Axon Terminals A-Axon Terminals & Varicosities

Somatic V. Autonomic Peripheral components found outside the CNS

S- Axon only A- Pre-ganglionic Axons, Ganglia, Post-ganglionic Neurons

Somatic V. Autonomic Effects "function" on target tissue

S-Excitatory *only* (muscle contracts) A-Both-Excitatory and Inhibitory

The effects of muscarinic receptor activation

SLUD Salivation Lacrimation Urination Defecation (Eyes too but not in acronym)

Peripheral Nervous system's two motor systems

SNS and ANS

mydriasis

SYM- NE→α-1 adrenergic = pupil dilation

Sympathetic Overview

Secretes Norepinephrine and epinephrine Relaxes - Pupils(dilate), airways, bladder Stimulates- release of insulin&pancreatic enzymes Inhibits- stomach&GI motility/secretions, gallbladder, saliva Promotes-ejaculation sex organs ↑ - heart rate

How is the adrenal cortex regulated?

Secretions of hormones from bloodstream

Autonomic Nervous System

Sounds like Automatic (Autonomous-self governing) Delivers info. to organs

Excitatory Function

Stimulates brain overactive transmitters

Controls Organs under STRESS

Sympathetic

Three synaptic regions of SNS

Sympathetic Chain ganglia Splanchnic Nerves Adrenal Medulla

Majority of sweat glands are what kind of receptor?

Sympathetic cholinergic receptors for ACh

What is the Adrenal medullas response to ACh binding at nicotinic receptors?

The modified sympathetic ganglia secretes epinephrine

WHY? If a person has been nerve gassed (i.e. exposed to one of the anticholinesterases), one symptom of the condition may be pin-point pupils.

The muscles controlling pupil constriction are cholinergic. The cholinesterase is inhibited thus allowing the acetylcholine to stay in the synaptic gap longer and overstimulating the constrictors.

Angry people can often be seen to have very dilated pupils. Why?

The muscles that control pupil dilation have adrenergic receptors so that the epinephrine released during emotional excitement will cause the pupils to dilate.

Sympathetic Location of spinal cord exit

Thoracolumbar

Sympathetic NS "aka"

Thoracolumbar (thoracic and lumbar)

Neurons exit spinal cord at __________________&__________________ in the sympathetic system

Thorax; Lumbar

Sympathetic chain ganglia

Two chains parallel to spinal cord.

The axons of postganglinic autonomic nerves have localizes swellings called _________________________ that contain the neurotransmitter and allow _____________________(4 words) to be formed with the target cells.

varicosities synapses along the axon

Parasympathetic NS Effects

↑ salivation ↑ lacrimation (tearing) ↑ urination ↑ digestive functions ↑ defecation Favors body fxns that can calm, conserve & restore body energy Reduces activites or fxns that consume energy