Dopamine Flashcards
One of the following is NOT CORRECT:
a. Catecholamines dopamine, norepinephrine and epinephrine are found both in the CNS and PNS
b. Tyrosine hydroxylase is the rate-limiting enzyme for the biosynthesis of catecholamines
c. Endogenous L-Dopa is efficiently converted to dopamine by tyrosine hydroxylase
d. Conversion of tyrosine to L-dopa and L-dopa to dopamine occurs in the cytosol.
c. Endogenous L-Dopa is efficiently converted to dopamine by tyrosine hydroxylase (dopa decarboxylase)
TRUE of dopamine receptors:
a. D1 receptors inhibit adenylyl cyclase activity while D2 receptors stimulate this enzyme. (D1 stimulates while D2 inhibits)
b. Dopamine receptors are found exclusively in the brain. (some exist in the kidney)
c. Stimulation of D1-like receptors (D1 and D5) results in depletion of cyclic AMP (increase in cyclic AMP)
d. The most striking pharmacological difference among D1 and D5 receptors is the high affinity of D5 receptors for dopamine.
d. The most striking pharmacological difference among D1 and D5 receptors is the high affinity of D5 receptors for dopamine.
One of the following is NOT TRUE for D2-like receptors:
a. D3 receptors have high affinity for typical antipsychotics (atypical)
b. D4 receptors have high affinity for atypical antipsychotic drug clozapine
c. D2L, an isoform of D2 receptors act primarily at postsynaptic sites.
d. D2S, an isoform od D2 receptors act primarily at presynaptic sites
a. D3 receptors have high affinity for typical antipsychotics (atypical)
Within the basal ganglia, the areas richest in dopamine are the:
a. Putamen
b. Globus palidus
c. Pars compacta
d. Caudate
c. Pars compacta
Drug-induced parkinsonian syndromes and tardive dyskinesia are prone to occur when the drug competitively bind to____ receptor.
a. D1
b. D2
c. D3
d. D4
b. D2
One of the following statements is NOT CORRECT:
a. Dopamine can very well cross the blood brain barrier.
b. The addition of dopadecarboxylase inhibitor (carbidopa or benzerazide) to L-dopa results in an increase concentration of dopamine in the brain
c. Catechol O-methyltransferase inhibitor prolongs the effect of levodopa.
d. A functional equilibrium exists in the striatum between the excitatory activity of ach and the inhibitory activity of dopamine
a. Dopamine can very well cross the blood brain barrier. (The immediate precursor L-dopa is the one which crosses the BBB)
The 5 types of dopamine receptors are found in differing concentration in the brain. One of the following is FALSE:
a. D1 and D2 are highly concentrated in the frontal cortex
b. D3 is found in the nucleus accumbens
c. D4 is found in the limbic system and frontal cortex
d. D5 is found in the hippocampus
a. D1 and D2 are highly concentrated in the frontal cortex (striatum)
Match the drug Pramipexole with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
b. dopamine agonist
Match the drug Amantadine with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
c. Glutamate antagonist
Match the drug Biperiden with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
d. anticholinergic
Match the drug Entacapone with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
e. COMT inhibitor
Match the drug Ropinerole with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
b. dopamine agonist
Match the drug Rasagiline with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
f. MAO-inhibitor
Match the drug Trihexyphenidyl with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
d. anticholinergic
Match the drug Selegiline with the mechanism of action:
a. L-dopa
b. dopamine agonist
c. Glutamate antagonist
d. anticholinergic
e. COMT inhibitor
f. MAO-inhibitor
f. MAO-inhibitor
