Autonomic System Flashcards
What NT is @ all ganglionic junctions in the PNS?
Ach
The _________ receptor via the NT _________ is the only cholinergic receptor found in a sympathetic neuronal pathway that acts on what end target organ?
Muscarinic receptor
Ach
Sweat glands
What % does the adrenal medulla release NE and Epi comparitively into the blood stream?
Epi = 80-90%
NE = 10-20%
Is Ach a tertiary or quaternary ammonium ester
Quaternary
Doesnt cross BBB
Which crosses the BBB, tertiary or quaternary
Tertiary
Name the 5 key elements of NT fxn
Synthesis
Storage
Release
Termination of action
Receptor effects
Ach is hydrolzed in ___ ms by acetylcholinesterase
15ms
AchE metabolizes ________ molecules of Ach in 1 sec
25,000
2 other names for AchE
True cholinesterase
Specific cholinesterase
Is Ach recycled or reused?
No
Adrenergic fibers are stimulated by _____
Ach
What 2 NTs are in adrenergic near-effector junctions
NE
Dopamine
Anatomically analogous to post-ganglionic sympathetic fibers
Adrenal medullary cells
What 2 adrenergic receptors are found on the presynaptic membrane
A2
B1??
Which adrenergic receptor fxns via positive feedback
B1
Denervation supersensitivity is an extreme form of _____-regulation
Up-regulation
What 4 adrenergic receptors stimulation adenylyl cyclase?
B1 B2 B3
D1
What 2 adrenergic receptors inhibit adenylyl cyclase?
A2
D2
Prototype for sympathomimetics
Phenylethylamine
Prototype for beta antagonists
Propranolol
What receptor is found on PNS & SNS autonomic ganglia
Nn receptors
This NT is probably a postganglionic sympathetic transmitter in renal blood vessels
Dopamine
This NT may have presynaptic effects on excitatory ENS nerve terminals & has some relaxant effects on the gut.
GABA
This NT is an important transmitter or cotransmitter at excitatory neuron-to-neuron junctions in the ENS
Serotonin
Which M receptors increase IP3/DAG/Ca++
M1 M3 M5
Which M receptors inhibit adenylyl cyclase & open K+ channels
M2 M4
Which N receptor is somatic
Nm
This type of receptor opens Na+ & K+ channels causing depolarization
N receptors
Which M receptors synthesize and release EDRF
M3 M5