A Phase I, Healthy Volunteer Positron Emission Tomography Study

Positron Emission tomography scans. Part 1of the study : 4 subjects will receive 2 scans a day for 1 day with PET ligand administered in tracer quantities.

If none of the data from Cohort 2 is informative, then: 2) an additional 3 subjects will receive 2 Scans on Day 1 and 1 scan on Day 2 following 3 different doses of PF-03654746. Doses will be determined based upon the outcome of the first intervention.

If none of the data from the previous interventions are informative, then: 3) an additional 3 patients will receive 2 scans on Day 1 and 1 scan on Day 2 following three different doses of PF-0365476. Doses will be determined based upon the outcomes of the previous interventions.

"Part 2 of the study will have 3 possible interventions:~1\) 3 subjects in Cohort 2 will receive 2 scans on Day 1 and 1 scan on Day 2 following 3 different doses of PF-03654746 (0.5 mg, 1.5 mg, 4 mg)."