Exam 3 Flashcards
Parasympathetic Nervous System (ANS subset)
rest and digest
conserve energy
Sympathetic Nervous System (ANS subset)
fight or flight
(continuously active)
ANS has a two neuron system what are the neurons called
preganglionic and postganglionic
(synapse combines them together)
What molecule has to be produced within a neuron, released when stimulated (ca2+ dependent), inactivated after release, and produce physiological responses
neurotransmitters
What system has a NT that is ACh -> cholinergic transmission
parasympathetic system (rest and digest)
In the parasympathetic system what is released at the first synapse and what is released at the second synapse
preganglionic: ACh (binds to soma receptors)
postganglionic: ACh (activates receptors in tissue to produce effect)
Synapses in pre and postganglionic axons in parasympathetic ganglia are terminal ganglia and intramural ganglia what do they do
terminal ganglia: close to target tissue
intramural ganglia: in target tissue
What are the two systems in the parasympathetic system (cholinergic system)
Parasympathetic system: Contains ganglia
Somatic Nervous System: NOOO ganglia
What is the somatic nervous system, what does it activate, how is it activated
one neuron pathway
CNS to skeletal muscle (NO ganglia)
Motor neurons are myelinated
NT is ACh
Activates muscle contraction
ACh is synthesized in the ________ by acetylation of choline
cytoplasm
Where is Choline acetyltransferase (ChAT) synthesizes and transported
synthesized in soma and transported down axon to nerve terminal (it marks cholinergic neurons)
What two things are needed for ACh synthesis
AcetylCoA from pyruvate
Choline
What are the two places you can get choline
diet
liver
(choline is formed from ACh metabolism)
Choline is recycled to be resued for ACh synthesis, it is transported inside neurons with what and by what transporter
Transported with Na+ by choline transporter (CHT1)
(Rate limiting step in ACh synthesis, high affinity)
High choline demand -> _____ affinity choline uptake (LACU) system assists in transporting additional choline into ________
low affinity
choline into neurons
CHT1 is a symporter, what does it symport
Choline and Na+ into cell
(needs Na+ /K+ ATPase antiport)
What does hemicholinium (hemicholine) do
blocks the transporter of CHT1
-indirect acetylcholine antagonist decreases ACh synthesis
ACh is stored in small synaptic vesicles which protect them from what
degregation
What is vesicular acetylcholine transporter (VAChT)
(Used for storage of ACh)
Located in the membrane of vesicles and relies on the H+ pump
What is the mechanism of the VAChT (vesicular acetylcholine transporter)
Antiporter
transports ACh inside the vesicles in exchange for protons
H+ are provided by the proton pump
What do vesamicols do to VAChT
They decrease ACh release
Depletion of ACh at synpase
(noncompetitive and reversible inhibitor)
How is ACh released from the synaptic vesicles
- Axon potential throughout the anion
- Activation of voltage-gated Ca2+ channels
- Exocytosis
ACh release is blocked by botulinum and tetanus toxins from __________
Clostridium
Transient vesicle fusion requires _________ proteins and Ca2+
SNARE
(SNARE proteins = soluble NSF attachment protein receptor, NSF = N-ethylmaleimide sensitive fusion proteins)