Autonomic Flashcards
Where do parasympathetic pre ganglionic fibers originate?
- CR III, VII, IX, & X
- In sacral segments
Where do sympathetic preganglionic fibers originate?
Thoracic & lumbar segments
Define: Adrenergic
Nerve ending that releases NE
Define: Adrencoceptor (adrenergic receptor)
Receptor that binds & is activated by 1 of the catecholamine transmitters/hormones
Define: Cholinergic
Nerve ending that releases acetylcholine
Define: Cholinoceptor (cholinergic receptor)
Receptor that binds & is activated by acetylcholine
Define: Postsynaptic receptor
Receptor located on distal side of a synapse
Define: Presynaptic receptor
Receptor located on the nerve ending from which the transmitter is released
- Modulates the release of transmitter
Define: Baroreceptor reflex
Neuronal homeostatic mechanism
- Maintains constant BP
Define: dopaminergic
Nerve ending that releases dopamine
Define: Homeostatic reflex
Compensatory mechanism for maintaining a body fxn at a predetermined level
- Ex. Baroreceptor reflex
Where is M1 located? & What is its fxn?
- Nerve endings
- Increases IP3, DAG cascade
Where is M2 located? What is its fxn?
- Heart, nerve endings
- Decreases cAMP, activated K channels
Where is M3 located? What is its fxn?
- Effector cells, SM cells, glands, endothelium
- Increases IP3, DAG cascade
Where is a1 located? What is its fxn?
- Effector tissues, SM, glands
- Increases Ca, causes contraction, secretion
Where is a2 located? What is its fxn?
- Nerve endings, SM
- Decreases transmitter release, causes contraction
Where is β1 located? What is its fxn?
- Cardiac muscle, juxtaglomerular apparatus
- Increases HR, force, & renin release
Where is β2 located? What is its fxn?
- SM, liver, heart
- Relaxes SM
- Increases glycogenolysis & HR
- Force
Where is β3 located? What is its fxn?
- Adipose cells
- Increases lipolysis
Where is D1 located? What is its fxn?
- SM
- Relaxes renal SM
What receptors are involved in the ciliary muscle? What do they do?
- Sympathetic: β relaxes
- Parasympathetic: M3 contracts
What receptors are involved in the SA node? What do they do?
- Sympathetic: β1 & β2 accelerates
- Parasympathetic: M2 decelerates
What receptors are involved in contractility of the heart? What do they do?
- Sympathetic: β1 & β2 increases
- Parasympathetic: M2 decreases
What receptor is involved in the myenteric plexus (GI)? What does it do?
Parasympathetic: M1 activates
What receptors are involved in the liver? What is their action?
β2, a
Sympathetic: Gluconeogenesis
What receptor is involved in the kidney & what is its action?
β1
Sympathetic: Renin release
What receptors are involved in the bronchiolar SM? What are their actions?
β2: Sympathetic, relaxes
M3: Parasympathetic, contracts
What is the action of local anesthetics?
Block: Na channels & conduction
What is the action of Reserpine?
Prevents storage, depletes
What is the action of amphetamines?
Promote release
What is the action of cocaine & tricyclic antidepressants?
Inhibit uptake, increase transmitter effect on postsynaptic receptors
What is the action of Propranolol?
Binds β receptors; prevents activation
What is the action of Nicotine?
Binds nicotinic receptors; opens ion channel in post-synaptic mem
What is the action of Bethanechol
Binds & activates muscarinic receptors
What is the action of Neostigmine?
Inhibits enzyme; prolongs & intensifies transmitter action
