6. ANS II

Question 1

Describe the use of tyrosine in the production of noradrenaline.

Answer 1

Tyrosine from food is hydroxylated by Tyrosine hydroxylase to make L-DOPA.

Question 2

Describe the use of L-DOPA in the production of noradrenaline

Answer 2

L-DOPA is decarboxylated by Dopa-decarboxylase to make Dopamine.

Question 3

Describe the use of dopamine in the production of noradrenaline.

Answer 3

Dopamine is hydroxylated by Dopaminebetahydroxylase to make Noradrenaline.

Question 4

Describe the use of noradrenaline in the production of adrenaline

Answer 4

PNMT turns it into adrenaline.

Question 5

Describe the release of noradrenline.

Answer 5

-Stored in vesicles with ATP and Chromogranin.
-released via a transport mechanism driven by a proton gradient.

Question 6

Describe uptake 1 of noradrenaline.

Answer 6

Located at the nerve terminal uses energy and requires a Na+ gradient to take from the synaptic cleft to the nerve terminal.

Question 7

Describe the affinity and capacity of noradrenaline uptake 1 mechanism and what this means for rate of uptake at low and high concentrations

Answer 7

High affinity and low capacity so works quickly at low concentrations but gets saturated at higher concentrations.

Question 8

Describe the affinity and capacity of noradrenaline uptake 2 mechanism and what this means for rate of uptake at low and high concentrations

Answer 8

Low affinity but high capacity so works very slowly at low concentrations but quick at high concentrations and doesnt get saturated easily.

Question 9

Name the drug that inhibits uptake 1 mechanism of noradrenaline.

Answer 9

Guanethidine.

Question 10

Name the drug that inhibits uptake 2 mechanism of noradrenaline.

Answer 10

Cortisol.