Intro to Autonomics

Question 1

acetylcholine is synthesized in the ____ from acetyl-CoA and choline, a reaction catalyzed by ____

Answer 1

acetylcholine is synthesized in the cytoplasm from acetyl-CoA and choline, a reaction catalyzed by choline acetyltransferase (ChAT)

Question 2

acetyl CoA is synthesized in the ___

choline is transported from the extracellular fluid into the neuron terminal by a ____ carrier (CHT1)

Answer 2

acetyl CoA is synthesized in the mitochondria

choline is transported from the extracellular fluid into the neuron terminal by a sodium-dependent carrier (CHT1)

Question 3

what is the rate-limiting step for the synthesis of ACh?

Answer 3

the uptake of choline by the sodium-dependent carrier (CHT1) is the rate-limiting step

Question 4

ACh is transported from the cytoplasm into vesicles by means of a carrier protein on the vesicle membrane called the vesicular ACh transporter (VAChT) which is an ___ that couples an influx of ___ with an efflux of ____

Answer 4

ACh is transported from the cytoplasm into vesicles by means of a carrier protein on the vesicle membrane called the vesicular ACh transporter (VAChT) which is an antiporter that couples an influx of ACh with an efflux of H+

Question 5

name the 3 locations where the M1 receptor is found

Answer 5

ganglia –> depolarization

CNS –> increased cognitive function

vomiting center –> emesis

Question 6

name 2 locations where the M2 receptor is found

Answer 6

heart –> cardiac inhibition

presynaptic nerve terminals –> inhibition of ACh release

Question 7

name 3 locations where the M3 receptor is found

Answer 7

smooth muscle –> contraction

secretory glands –> secretion

vascular endothelium –> vasodilation