Chapter 52. Parkinson Disease
What is the primary neurotransmitter deficiency in PD?
Answer b is correct. The deficiency is caused by a loss of nigrostriatal neurons in the substantial nigra pars compacta.
Answer a is incorrect. There is a relative overactivity of acetylcholine in PD.
Answer c is incorrect. Adrenergic pathways may be affected by PD, but norepinephrine is not the primary neurotransmitter deficiency.
Answer d is incorrect. Serotonergic pathways may be affected by PD, but serotonin is not the primary neurotransmitter deficiency.
What is the primary goal of PD treatment?
a. Cessation of disease progression
b. Facilitate an increase in the storage capacity of dopamine
c. Maintenance of functional ability
d. Reversal of neuronal loss
Answer c is correct. The control of motor symptoms ultimately allows the PD patient to continue to function and perform normal activities of daily living. As there is no medication that stops disease progression, the goal is to maintain the patient’s ability to function as long as possible.
Answer a is incorrect. There are currently no therapies that stop the progression of PD.
Answer b in incorrect. As PD progresses, additional neurons will cease to function and dopamine levels will continue to decrease. As there is no medication that stops disease progression, there is no medication that increases dopamine storage capacity.
Answer d is incorrect. There are no medications capable of reversing the loss of nigrostriatal neurons.
What is the role of carbidopa in the treatment of PD?
a. It inhibits acetylcholine.
b. It inhibits dopa decarboxylase.
Answer b is correct. Carbidopa inhibits dopa decarboxylase to prevent the conversion of levodopa to dopamine in the periphery allowing the drug to cross the blood brain barrier.
Answer a is incorrect. Anticholinergics (such as benztropine) inhibit acetylcholine.
Answer c is incorrect. COMT inhibitors (tolcapone and entacapone) inhibit COMT.
Answer d is incorrect. MAO inhibitors (selegiline and rasagiline) inhibit MAO.
SP was diagnosed with PD 7 years ago. ...