Dissociative changes in Bmax and KD of dopamine D2/D3 receptors with aging observed in functional subdivisions of striatum: A revisit with an improved data analysis method

摘要

Separate measurements of Bmax, the density of available receptors and KD, the equilibrium dissociation constant in the human brain with positron emission tomography (PET) have contributed to our understandings of neuropsychiatric disorders, especially with respect to the dopamine D2/D3 receptor system. However, existing methods have limited applications to the whole striatum, putamen or caudate nucleus. Improved methods are required to examine Bmax and KD in detailed functional striatal subdivisions that are becoming widely used.MethodsIn response, a new method (bolus-plus-infusion transformation, BPIT) was developed. After completion of a validation study for [¹¹C]raclopride scans involving 81 subjects, age-associated changes in Bmax and KD were examined in 47 healthy subjects ranging from 18 to 77 years old.