ANS Overview Flashcards
Sympathetic (ANS)
Fight or Flight
Parasympathetic (ANS)
Rest and Digest
Preganglionic neuron
Located in CNS
Postganglionic neuron
Peripheral neuron, and projects to the target organ
Acetylcholine (ACh)
A primary transmitter of all preganglionic neurons and also a transmitter in PSNS postganglionic neurons
Norepinephrine (NE)
Transmitter in most SNS postganglionic neurons
Neuron length
PSNS= long to short. SNS= short to long
Sweat gland neurotransmitter
Postganglionic= norepinephrine for stress or acetylcholine for thermoregulation
Receptor agonist
Mimic neurotransmitters and activate receptors
Receptor antagonist
Block neurotransmitters and block the endogenous neurotransmitters from activating receptors
ParasympathOMIMETIC
Mimic ACh (AGONIST)
ParasympathOLYTIC
Block ACh (ANTAGONIST)
SympathOMIMETIC
Mimic NE (AGONIST)
SympathOLYTIC
Block NE (ANTAGONIST)
Muscarinic Cholinergic Receptor (M1,3,5)
Signal via Gq with second messengers IP3 and DAG
Muscarinic Cholinergic Receptor (M2,4)
Signal via Gi pathway and inhibits second messenger cAMP
Nicotinic Cholinergic Receptor
Ionotropic which opens ligand-gated Na+ channels
Adrenergic Receptor a1
Signal via Gq pathway with second messengers IP3 and DAG
Adrenergic Receptor a2
Signal through Gi which inhibits adenylyl cyclase and reduces cAMP
Adrenergic Receptor B1,2,3
Signal through Gs which activates adenylyl cyclase and increases cAMP
PSNS effect on EYE
Contraction of the pupil (miosis) and focusing of the lens
PSNS effect on GLANDS
Increase secretion
PSNS effect on AIRWAY
Constrict bronchi and secretion of mucous
PSNS effect on HEART
Decrease rate (bradycardia) and decreased force
