POSITRON EMISSION TOMOGRAPHY STUDY OF HUMAN NARCOLEPSY - NO INCREASE IN STRIATAL DOPAMINE D-2 RECEPTORS

We investigated dopamine D-2 receptors in the caudate nucleus and putamen with positron emission tomography in seven patients with narcolepsy and seven healthy controls by using [C-11]raclopride as a ligand. We applied an equilibrium method and Scatchard principle to give a quantitative estimation of the number (B-max) and dissociation constant (K-d) Of the receptors. Both the B-max and K-d were within the normal range in the caudate nucleus and putamen in narcoleptic patients. We found no evidence for increased D-2 receptor binding in narcolepsy.