CH 14 autonomic nervous system

Autonomic nervous system

regulates involuntary bodily functions

Ganglion

collection of nerve cell bodies in the peripheral nervous system

• acts as relay station for nerve signals

Parasympathetic

promotes maintenance functions and contains body energy (rest + digest)

sympathetic

mobilizes body energy during activity (stress) (flight or fight)

sympathetic trunk

sympathetic chain where all sympathetic ganglia that runs up and down the spinal cord

White ramus/Gray ramus communicans

specifically sympathetic rami, carries autonomic functions only, communicate with the sympathetic trunk

Adrenergic receptors

receptors that recognize catecholamines like epinephrine (adrenaline) and Norepinephrine (noradrenaline)

Nicotinic

located on skeletal muscle, also located on post gang neurons and adrenal medullary cells

Effect of binding: excitation

Cholinergic receptors

nicotinic and muscarinic

ACh recognizing receptors

muscarinic

located on all parasympathetic target organs as well as limited sympathetic targets (eccrine sweat glands, etc)

Effect of binding: activation/ excitation

adrenergic receptors

catecholamine recognizing receptors

Beta 1

receptor located in heart; They regulate the "fight-or-flight" response by increasing heart rate

beta 2

located in lungs; bronchodilation (opening airways), vasodilation (widening blood vessels),

beta 3

located in fat (adipose tissue); regulate metabolism and smooth muscle relaxation; lipolysis

lipolysis

breakdown of fat

alpha 1

located in blood vessels; Constricts most blood vessels except the brain,heart, and skeletal muscles

alpha 2

located in moderate amount of sympathetic release/activity; Inhibits NE release of adrenergic terminals

Activators

enhance sympathetic activity by binding to adrenergic receptors, increase NE release

Ex. albuterol and phenylephrine

Inhibitors

decrease sympathetic activity by blocking adrenergic receptors

• ex. propanol