Physiology Of The ANS Receptors Flashcards
What are actions of beta 1 receptors?
Increase HR, conduction and strength of contraction in the heart
Decrease saliva secretion
Lipolysis in adipose tissue
Control of blood flow within the kidney
What are the actions of alpha 1 receptors?
Increase contraction of the skin and gut vasculature + skeletal muscle vasculature
Contraction of sphincters in the GI tract and bladder sphincter
Increased contraction of the radial muscle of the iris in the eye
Contraction of piloerector muscles causing goosebumps
Gluconeogenesis and glycogenolysis in the liver
What are the actions of beta 2 receptors?
Decreased contraction of vasculature skeletal muscle
Decreased contraction of bronchioles (relaxation)
Decreased contraction of smooth muscle of the GI tract wall (relaxation)
Relaxation of detrusor muscle of the bladder
Decreased contraction/relaxation of ciliary muscle of the lens
Gluconeogenesis and glycogenolysis in the liver
What are the actions of alpha 2 receptors?
Decrease contraction of smooth muscle walls of the GI tract
Dilation/erection of male genitalia
Also found in platelets —> increase clotting activity/platelet activation via epinephrine
What are the actions of beta 3 receptors?
Lipolysis in adipose tissue
What are the functions of all the combined effects of activating the alpha and beta adrenergic receptors during a sympathetic response?
Increase O2 delivery to cells by increasing blood flow
Direct blood flow to active tissues (skeletal muscle particularly)
Allow air flow into lung more freely
Decrease digestion and absorption (redirect blood way from the GI tract)
Prevent urination
Increase ability to see distance clearly (looking for an escape)
Cool down the body via sweating (lose heat being generated)
Increase in release of energy stores such as glucose and FFAs (provides energy)
What are the actions of M2 receptors of the parasympathetic system?
Decrease HR and conduction velocity
Decrease contraction of smooth muscle sphincters in the GI tract and maybe the bladder
What are the actions of M3 receptors of the parasympathetic system?
Decrease contraction strength in the atria
Increase contraction in bronchioles
Increase contraction of smooth muscle walls of the GI tract + increase gastric acid and pancreatic secretion
Increase contraction of detrusor muscle of bladder
Increase contraction of circular muscles (iris) and ciliary muscle (lens) in the eye
Maybe increases secretion of lacrimal glands
What are the actions of M1 receptors in the parasympathetic response?
Increase saliva secretion and gastric acid secretion (maybe)
Increase lacrimal gland secretion
What happens to vasculature and skin changes during a parasympathetic response?
Parasympathetic NS has no action on these systems so instead the sympathetic system is completely turned off
What is the collective action of all the receptors being activated during a parasympathetic response?
Return cardiac work load to normal
Slow down breathing -> redirect O2 -> decrease ventilation
Initiate digestion (energy coming from the gut instead of energy stores)
Allow excretion of wastes through urination
Activate near vision (relax)
Produce tears (protecting blood flow)
What function do M3 receptors have in the sympathetic response?
Increase secretion of sweat glands for thermoregulation
