Question 1

A decrease in dopamine influence in the basal ganglia leads to increased influence of ______,which can be treated to some extent by _______.&#10;A)acetylcholine;anticholinergic drugs&#10;B)norepinephrine;dopamine antagonists&#10;C)acetylcholine;cholinesterase inhibitors&#10;D)norepinephrine;anticholinergic drugs&#10;E)acetylcholine;dopamine antagonists

Accepted Answer

A decrease in dopamine in the basal ganglia leads to an increased influence of acetylcholine. This imbalance can be treated with anticholinergic drugs, which reduce the effects of acetylcholine, helping to restore balance and improve symptoms.

Question 2

Parkinson disease typically occurs because of the slow,progressive degeneration of specific _______-secreting neurons in the ______.&#10;A)acetylcholine;cortex&#10;B)norepinephrine;cerebellum&#10;C)dopamine;basal ganglia&#10;D)serotonin;limbic system&#10;E)glutamate;brain stem

Accepted Answer

Parkinson disease is caused by gradual loss of dopaminergic neurons in the substantia nigra region of the brain, which is part of the basal ganglia. This loss of dopamine leads to the characteristic motor symptoms of Parkinson disease.

Question 3

To prevent premature conversion of L-DOPA to dopamine in the bloodstream,L-DOPA is often administered with carbidopa because carbidopa is:&#10;A)a dopamine antagonist.&#10;B)an anticholinergic drug.&#10;C)a cholinesterase inhibitor.&#10;D)a peripheral decarboxylase inhibitor.&#10;E)an antioxidant.

Accepted Answer

Carbidopa is a peripheral decarboxylase inhibitor, which means it inhibits the enzyme that converts L-DOPA to dopamine in the bloodstream, allowing more L-DOPA to reach the brain to be converted to dopamine. This results in a better therapeutic effect and fewer side effects such as nausea and vomiting.

Question 4

All of the following drugs can be used to treat Parkinson disease EXCEPT:&#10;A)L-DOPA.&#10;B)dopamine antagonists.&#10;C)catechol-O-methyltransferase (COMT)inhibitors.&#10;D)anticholinergic drugs.&#10;E)MAO type b inhibitors (e.g. ,selegiline [Eldepryl]).

Accepted Answer

All of the listed drug types are used to treat Parkinson disease, except for dopamine antagonists. Dopamine agonists, such as L-DOPA, mimic the action of dopamine in the brain. COMT inhibitors prolong the effect of dopamine by blocking its breakdown. Anticholinergic drugs reduce the activity of acetylcholine, which is in excess in Parkinson disease. MAO type b inhibitors, like selegiline, also increase dopamine levels by blocking its breakdown. However, dopamine antagonists block the action of dopamine and are typically used to treat conditions where dopamine is in excess, such as psychosis or hyperprolactinemia.

Question 5

After entering the brain,levodopa is transformed into dopamine,by the enzyme:&#10;A)dopa transmutate.&#10;B)dopa decarboxylase.&#10;C)monoamine oxidase.&#10;D)acetylcholinesterase.&#10;E)sodium-potassium ATPase.

Accepted Answer

Levodopa is transformed into dopamine by the enzyme dopa decarboxylase. This is the first step in the synthesis of dopamine within the brain.

Question 6

Drugs such as selegiline (Eldepryl)that inhibit the monoamine oxidase type B (MAOB)enzyme may be helpful in Parkinson disease because:&#10;A)they increase dopamine absorption from the gastrointestinal tract.&#10;B)they increase the conversion of levodopa to dopamine in the bloodstream.&#10;C)they decrease the movement of levodopa across the blood-brain barrier.&#10;D)they decrease the breakdown of dopamine in the brain.&#10;E)they increase the breakdown of acetylcholine in the brain.

Accepted Answer

MAOB breaks down dopamine in the brain, so inhibiting this enzyme would decrease the breakdown of dopamine in the brain, leading to higher levels of dopamine and improved symptoms in Parkinson disease. Choices A, B, and E are incorrect because they do not directly address the mechanism of action of MAOB inhibitors. Choice C is incorrect because it would actually decrease the amount of levodopa that reaches the brain, leading to worsened symptoms.

Question 7

Oral administration of dopamine is NOT effective in the treatment of Parkinson disease because dopamine is:&#10;A)degraded into L-DOPA in the blood stream.&#10;B)digested in the stomach.&#10;C)unable to pass from the blood stream into the brain.&#10;D)degraded by dopa decarboxylase in the blood stream.&#10;E)none of the above

Accepted Answer

Dopamine cannot cross the blood-brain barrier, which prevents it from entering the brain from the bloodstream, making oral administration ineffective for treating Parkinson's disease.

Question 8

Neuronal death that occurs in Parkinson disease may ultimately be caused by the formation of harmful by-products of oxygen metabolism,better know as:&#10;A)free radicals.&#10;B)dopamine antagonists.&#10;C)cholinesterase inhibitors.&#10;D)monoamine oxidase inhibitors.&#10;E)decarboxylase inhibitors.

Accepted Answer

Free radicals are reactive molecules that can damage cells and ultimately lead to cell death. In Parkinson's disease, free radicals can be formed during the metabolism of dopamine in neurons, leading to oxidative stress and neuronal damage.

Question 9

Levodopa administration can help resolve the symptoms of Parkinson disease,but this drug can also cause:&#10;A)gastrointestinal problems.&#10;B)cardiac arrhythmias.&#10;C)postural hypotension.&#10;D)dyskinesias.&#10;E)all of the above

Accepted Answer

Levodopa administration can cause gastrointestinal problems such as nausea and vomiting, cardiac arrhythmias, postural hypotension, and dyskinesias. Therefore, all of the above options are correct.

Question 10

Catechol-O-methyltransferase (COMT)inhibitors such as entacapone (Comtan)and tolcapone (Tasmar)may enhance the effects of levodopa because these drugs:&#10;A)decrease the breakdown of dopamine in the brain.&#10;B)increase dopamine absorption from the gastrointestinal tract.&#10;C)prevent conversion of levodopa to an inactive metabolite in the bloodstream.&#10;D)increase the breakdown of dopamine in the brain.&#10;E)prolong the activity of acetylcholine in the brain.

Accepted Answer

COMT inhibitors prevent the conversion of levodopa to an inactive metabolite in the bloodstream, thereby enhancing the availability and effectiveness of levodopa.

Question 11

With regard to levodopa administration,&#34;end-of-dose akinesia&#34; describes the phenomenon where:&#10;A)a patient experiences hallucinations and other psychotropic effects.&#10;B)drug effects follow an on-off pattern throughout the day.&#10;C)levodopa seems to become less effective when it is administered for prolonged periods (3 to 4 years).&#10;D)the effectiveness of levodopa seems to wear off prior to the next dose.&#10;E)none of the above

Accepted Answer

The answer of With regard to levodopa administration,&#34;end-of-dose akinesia&#34; describes...

Deck 10: Pharmacologic Management of Parkinson Disease