| Autor: |
Carson RE; Positron Emission Tomography Department, National Institutes of Health, National Institutes of Mental Health, Bethesda, Maryland 20892-1180, USA., Breier A, de Bartolomeis A, Saunders RC, Su TP, Schmall B, Der MG, Pickar D, Eckelman WC |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism [J Cereb Blood Flow Metab] 1997 Apr; Vol. 17 (4), pp. 437-47. |
| DOI: |
10.1097/00004647-199704000-00009 |
| Abstrakt: |
Positron emission tomography and single-photon emission computer tomography receptor-binding ligands can be used to measure changes in neurotransmitter levels. In particular, amphetamine-induced dopamine release has been assessed with [11C]raclopride by paired bolus injections and with [123I]iodobenzamide by using a single bolus plus infusion (B/I) study. Here, we measured the change in [11C]raclopride-specific binding in rhesus monkeys after i.v. administration of 0.4 mg/kg amphetamine by using both the bolus and B/I paradigms. Paired bolus studies (control and postamphetamine) were analyzed using compartment modeling and graphical analysis with a new plasma metabolite model to measure the total distribution volume (VT). Specific binding, calculated with three measures linearly proportional to the binding potential, demonstrated a 22-42% reduction in the postamphetamine study. VT values from B/I studies were determined by the tissue-to-plasma ratio at equilibrium, in addition to the bolus methods. There was good agreement between the control VT values between bolus and B/I studies. The amphetamine-induced change in specific binding in B/I studies was 19 +/- 16%, measured directly from tissue radioactivity levels. This study demonstrates that stimulus-induced changes in specific binding can be measured with a single [11C]raclopride study using the B/I method. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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