measured by use of the probe [^18 F]fluorodopa, which can be taken up
by dopamine neurons and stored in their nerve terminals. Patients with
Parkinson’s disease show a sharp decrease in the amount of probe at the
neuron terminals as detected by the PET images. Efforts are underway
in a number of laboratories to utilize this technique to identify drugs that
can slow the disease progression in Parkinson’s patients.
CHAPTER 19 MOLECULAR IMAGING 419
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19.2 How is the chromophore of GFP related to the gene sequence?
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19.5 Why does wild-type GFP have absorption bands at 395 and 475 nm?
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19.8 Why does the spectrum of GFP have more than one absorption band that changes with pH?
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