Chapter 14: Autonomic Nervous System

Autonmic nervous sytem

Involuntary

f: overseas vital functions (ex: heart rate, digestive process)

sympathetic nervous system

fight or flight: stimulate

parasympathetic nervous system

rest and digest: slows/inhibit

preganglonic neuron

connects to CNS autonomic ganglion

Post-ganglion neuron

ganglion to effector site/target

ex: smooth muscle, cardiac muscle, glands, GI system

autonomic ganglion

cell body of second cell ( post-ganglion neuron)

Parasympathetic neurons

origin: craniosacral

preganglionic length: longer

postganglionic length: shorter

autonomic ganglion location: closer to target organ

postganglionic axon neurotransmitter released: ACh

target organ receptor: cholinergic

Sympathetic neurons

origin: thoracolumbar

Pre-ganglion length: shorter

postganglion length: longer

autonomic ganglion location: closer to spine

Postganglionic axon neurotransmitter realsed: NE or E

target organ receptor : adrenergic

alpha 1 - excitatory

ex: constrict blood vessel ( smooth muscle) makes muscle excited

beta 1 - exitatory

ex: speeds heart rate ( excites cardiac, kidney)

beta 2 - inhibitory

ex: relaxes airway ( relaxes smooth muscle)

Adrenergic

bind to NE or E

Cholinergic

Bind to ACh

Sympathetic chain

chain of ganglia on eitherside of spinal cord

adrenal medulla

releases hormones into bloodstream when stimulated

collateral ganglion

ganglion near target organ

heart

sympathetic effect : increase heart rate and force of contraction

parasympathetic effect:P decrease heart rate

bronchioles of lung

sympathetic effect: dilation

Parasympathetic effect: constriction

Pupils

sympathetic: dilation

Parasympathetic: constriction

Digestive tract activity and secretion

Sympathetic effect: relaxation ,decrease in secretion

Parasympathetic effect: contraction, increase

Metabolic rate

sympathetic effect: increase

parasympathetic: no effect

Urination

sympathetic: decrease

Parasympathetic: increase

fats/glucose( storage/release)

Sympathetic: increase release of glucose, stimulation of fat breakdown

Parasympathetic: no effect

blood vessels

sympathetic: dilation to skeletal muscles construction to skin

Parasympathetic: little/ no effect

sweat glands

Sympathetic: increase secretion of sweat

Parasympathetic: no effect

step 1: visceral reflex arc

1: sensory signals from the viscera and skin are sent by afferent sensory neurons to the brain to the brain or spinal cord.

step 3: visceral reflex arc

3: motor impulses dome the CNS are sent via efferent motor neurons in cranial and spinal nerves to autonomic

Step 2: visceral reflex arc

2: the stimuli are integrated by the CNS

step 4: visceral reflex arc

4: the autonomic ganglia send the impulses via other efferent motor neurons to various target organs where they trigger a motor response in the target cells

reticular formation

- regulates HR, BP, digestion, metabolic rate, respiration ,urine, sleep/wake, acid-base balance

hypothalamus

- boss of ANS

- instructs reticular formation

- regulates body temp, feeding behavior, fluid intake

visceral reflex arc

-sensory stimulus in an organ leads to predictable visceral motor response