Dopamine is a neurotransmitter involved in the reward pathways in the brain, and its decreased activity has been associated with
diseases such as Parkinson’s disease and attention-deficit/hyperactivity disorder (ADHD). Which of the following drugs is NOT a likely candidate to treat these diseases? A. Methylphenidate, a dopamine reuptake inhibitor
B. Amphetamine, a dopamine-releasing agent that triggers the release of dopamine into the synaptic cleft
C. Carbidopa, which enhances the availability of the dopamine synthesis precursors in the brain
D. Forskolin, a sensitizer of dopamine receptors
E. Chlorpromazine, a dopamine antagonist that binds to and inhibits dopamine receptors
The answer is E; Chlorpromazine, a dopamine antagonist that binds to and inhibits dopamine receptors
Explanation:
Chlorpromazine which is a dopamine antagonist is not a candidate to treat Parkinson's disease and attention-deficit/hyperactivity disorder (ADHD) because as a dopamine antagonist it works by binding to dopamine receptors but does not activate it, thus blocking the actions of dopamine or exogenous agonists.
The nucleus accounts for nearly all mass in an atom. It is positively charged. It is made up of protons and neutrons. The electron cloud surrounding the nucleus is 100,000 times the size of the nucleus.
