Anatomy 3, Class 9: Ans, Visceral Reflexes, Referred Pain, Drug Effects

Front 1

What does the ANS intervate?

Back 1

Cardiac and Smooth Muscle

and Glands

Front 2

What are the two neurons of the efferent pathways of the ANS?

Back 2

PREGANGLIONIC NEURON, which begins in the CNS and is lightly myelinated and has a thin preganglionic axon

GANGLIONIC NEURON is thinner and has an unmyelinated postganglionic axon

There is also an AUTONOMIC GANGLION

Front 3

What are the differences between the Sympathetic and Parasympathetic nervous system fibers?

Back 3

the sympathetic(flight and fright)has a short preganglionic and long postganglionic fibers

the parasympathetic has the opposite

Front 4

What are the differences between the Sympathetic and Parasympathetic neurotransmitters?

Back 4

the sympathetic division produces acetycholine and norepinephine

the parasympathetic only produces acetycholine

Front 5

What does the D Division refer to?

Back 5

The parasympathetic (resting and digesting)

digestion
defecation
diuresis

Front 6

What does the E Division refer to?

Back 6

the sympathetic (flight or fright)

exercise
exictement
emergency
embarrassment

Front 7

What is dual innervation refer to?

Back 7

the fact that both division of the ANS (para and sympathetic) are always on, but usually one is on a lot and the other is on only a little

rarly all or nothing

Front 8

Where are the orgins of the Sympathetic and Parasympathetic nervous systems?

Back 8

Sympathetic: thoracolumbar spinal cord

Parasympathetic: CRANIAL-SACRAL AREA!!

Front 9

What are the locations of the ganglia in the Sympathetic and Parasympathetic nervous systems?

Back 9

ParaSympathetic: EFFECTOR ORGANS (where they synapse in the terminal or intramural ganglia)

Parasympathetic: lie close to the spinal cord

Front 10

Why is the Parasympathetic nervous system also called the craniosacral division?

Back 10

because its fibers emerge from the brain stem and the sacrum

Front 11

What 3 cranial nerves contain parasympathetic outflow?

Back 11

CN 3 (Oculomotor)-pupillary constriction and lens bulging

CN 7 (Facial) - nasal and lacrimal glands

CN 9 (Glossopharyngeal) - Parotid salivary glands

*OF THESE THREE CN, ONLY THE PREGANGLIONIC FIBERS ARE WITHIN THE STATED CN, THE POSTGANGLIONIC FIBERS ARE WITHIN/OVERLAP CN 5(TRIGEMINAL)

Front 12

Why is CN 10 (Vagus) important to the Parasympathetic nervous system?

Back 12

1. accounts of 90% of all PREganglionic parasympathetic fibers in the body

2. innervates almost every organ of the thorax and abdomen

3. goes to esophagus, to aortic plexus and branch to abd organs (LIV, GB, ST, SI, KID, Pancreas and proximal half of LI

Front 13

Describe the sacral outflow of the parasympathetic nervous system?

Back 13

S2-S4 ventral rami, which form the pelvic (or splanchic nerves) which pass through the inferior hypogastric pelvic plexus

-afffects: distal LI, UB, ureters and reproductive organs

Front 14

Describe the thoracolumber outflow of the sympathetic nervous system?

Back 14

- cell bodies located in spinal cord from T1-L2

-VISCERAL MOTOR ZONES (lateral horns) are formed by preganlionic neurons in the spinal cord GRAY MATTER

-they enter the white rami communicates and then an adjoining chain or paravertebral ganglion that forms the sympathetic trunk or chain

-even though the fibers arise from thoracolumber the sympathetic trunks extend from the neck to the pelvis. There are 23 ganglia in each chain:
three cranial
eleven thoracic
four lumbar
four sacral
one coccygeal

Front 15

What three things can happen to a preganglionic axon in a ganglion?

Back 15

1- It can synapse within the ganglion to another neuron

2- It can ascend or descend to another ganglion

3- It can continue past the ganglion w/out synapsing (only in Abd/Pelvis = splanchnic nerves, anterior to spine)

Front 16

Describe the sympathetic pathways with ganglionic synapses.

Back 16

- POSTGANGLIONIC AXONS enter the VENTRAL or DORSAL RAMUS via the ""GREY RAMI COMMUNICATES"", they effect the skin, sweat glands, nad blood vessels and are unmyelinated

- fibers that go to the head arise from T1-T4 and synapse in the superior cervical ganglion

-Fibers that go to the thorax orginate from T1-T6 and synapse in the middle and inferior cervical ganglia

- Postganglionic fibers emerging from the middle and inferior cervical ganglia enter the cervical nerves C4-C8

Front 17

Describe the sympathetic preganglionic pathways that do not synapse in the chain ganglion.

Back 17

- thoracic, lumbar, and sacral splanchnic nerves contribute to the abdominal aortic plexus and synapse in the following order from superior to inferior:
"CELIAC
SUPERIOR MESENTERIC
INFERIOR MESENTERIC
INFERIOR HYPOGASTRIC"

*these are all named for the nerves that they are nearest

-Pathways to the ABD (T5-L2)
-Pathways to pelvis (T10-L2)

Front 18

Describe the sympathetic pathways with synapses in the adrenal medulla.

Back 18

-some fibers in the thoracic splanchnic pass through the celiac ganglion and synapse in the adrenal gland medullary cells causing secretion of norepinephrine and epinephrine into the blood

Front 19

Describe visceral reflexes.

Back 19

-sense chemical changes, strech (most painful) and irriation of the viscera

-very similar to a somatic reflex arc: each has a receptor, sensory neuronm integration center, motor neuron, and effector. The difference is that the motor chain has 2 neurons in a visceral arc (unlike skeletal where there's always one)

Front 20

How does referred pain work?

Back 20

-visceral pain afferents travel (highjack) along the same pathways as somatic pain fibers, which may explain why visceral pain may feel like somatic pain

Front 21

What is Atropine?

Back 21

Anticholinergic that blocks parasympathetic effects (Acetylcholine)

-it is used presurgically to prevent salivation and respiratory secretions and ophthmologically for pupil dilation

Front 22

What is neostigmine?

Back 22

an anticholinesterase (to prevent cholinestrase from braking down Acetylcholine)

-used to treat myasthenia gravis

Front 23

What is the effect of tricylic antidepressants?

Back 23

"PROLONGS ACTIVITY OF NE ON THE POSTSYNAPTIC MEMBRANE"

Front 24

What is the effect of sympathometics?

Back 24

OTC Drugs that stimulate a-adrenergic receptors

-treat colds, allergies, coughs, and nasal congestion

Front 25

What is the effect of B-Adrenergic blockers?

Back 25

reduces heart rate and prevent arrhythmias

Front 26

What happens with a release of NE?

Back 26

"SWEATY PALMS, INCREASED HEART RATE"

Front 27

How does a release of epinephrine effect the lungs?

Back 27

"IT DILATES THE BRONCHIOLES OF THE LUNGS"