Physiology of Autonomic Nervous System

The somatic and autonomic nervous systems are a subdivision of which nervous system?

Peripheral Nervous System (PNS)

What is the difference between the autonomic nervous system and the somatic nervous system?

Somatic controls voluntary movements where the autonomic controls involuntary activities without conscious thought or effort

What are 4 vital operations controlled by the autonomic nervous system?

Heart rate, breathing, digestion, pupil size

What are the three main functions of the ANS?

Maintain homeostasis, respond to stress or emergencies, repair body tissue

What is the neurotransmitter involved in acting on tissues for a parasympathetic response?

Acetylcholine (Ach)

What is the neurotransmitter involved in acting on tissues for a sympathetic response?

Norepinephrine (NE), Epinephrine, dopamine

What are physical responses stimulated by the SNS body response?

Increase in BP, HR, heart contractility, RR and blood to muscles. Decrease in digestion. Bronchodilation, pupil dilation, sweating, piloerection. Blood directed away from organs and sphincter constriction

What are physical responses stimulated by the PNS body response?

Pupils constrict, HR decreases, bronchoconstriction, GI motility increases, secretions increase, detrusor contacts

What type of response is the sympathetic nervous response?

Adrenergic

What are the two main receptors of Norepinephrine?

Alpa 1 and Beta 1

What are the main receptors of acetylcholine?

Muscarinic receptors

Where are muscarinic receptors located?

organs controlled by the PNS

Where are the receptors of acetylcholine located?

Brain, ANS, neuromuscular junctions, everywhere nerve meets muscle

What do alpha 1 receptors cause when stimulated?

Vasoconstriction, increases in BP, decrease in blood flow to skin/GI

What does acetylcholine do in the body when released?

Slows down the heart, is triggers the gut to respond, in triggers the bladder to empty, it constricts the pupils

What do beta 1 receptors cause when stimulated?

Increase in HR and contractility, increase in cardiac output

What state dose norepinephrine keep your body in? What are the effects?

Ready for action. Vasoconstriction to push blood to muscles, heart beats faster and stronger, pupils dilate, digestion slows

What are the two main receptors of Epinephrine?

Alpha 1, Beta 1, and Beta 2

What do beta 2 receptors cause when stimulated?

Bronchodilation, vasodilation to skeletal muscles

What state dose epinephrine keep your body in? What are the effects?

Full fight or flight response. Heart races, airways open, pupils dilate, blood shunts to muscles, glucose is released for energy

What are the main receptors for dopamine?

Dependent on the amount released

What are the effects of low doses of dopamine in the body?

Renal, mesenteric, and coronary vessel dilation leading to improved blood flow to kidneys and heart

What are the effects of moderate doses of dopamine in the body?

Stimulation of beta 1 receptors leading to increased heart rate and contractility

What are the effects of high doses of dopamine in the body?

Stimulation of alpha 1 receptors leading to vasoconstriction

The alpha receptors produce what general affects?

Clamp and control

Alpha 1 receptors produces what general affect?

Constriction

Where are alpha 1 receptors located?

Smooth muscle blood vessels, eyes, bladder, and prostate

Alpha 2 receptors produces what general affect?

Chill response

Where are alpha 2 receptors located?

Presynaptic nerve terminals, so the CNS

What actions do alpha 2 receptors produce when stimulated?

Inhibits norepinephrine release causing a decrease in sympathetic outflow and blood pressure

The beta receptors produce what general affects?

Boost and breathe

Beta 1 receptors produces what general affect?

Cardiac acceleration, effects on the heart

Beta 2 receptors produces what general affect?

Breathing and relaxation team, effects on the lungs

Where are beta 1 receptors located?

Heart

Where are beta 2 receptors located?

Lungs, skeletal muscle vessels, uterus, liver

What actions do beta 2 receptors produce when stimulated?

Bronchodilation, vasodilation in skeletal muscles, relax uterine muscle, increase glucose release

What type of response is the parasympathetic nervous response?

Cholinergic