Evaluation of the importance of rebinding to receptors in slowing the approach to equilibrium of high-affinity PET and SPECT radiotracers

Synapse
A N GiffordN D Volkow

Abstract

The importance of rebinding to receptors in influencing the kinetics of in vivo binding of PET and SPECT radiotracers was evaluated by examining the binding of a high-affinity D1 receptor radiotracer, [3H]SCH 23390, in tissue homogenates, living brain slices, and in vivo. In rat striatal homogenates, [3H]SCH 23390 binding reached equilibrium with a half-time of 6 min. By contrast, in striatal brain slices incubated in [3H] SCH 23390, the radioactivity levels in the slice increased in a linear fashion over the 4-h incubation, with no indication of an approach to equilibrium at the termination of the experiment. In in vivo experiments, [3H]SCH 23390 was given as a slow intravenous infusion to mice, using a paradigm that kept the plasma concentration at a constant level. Under these conditions, striatal [3H] SCH 23390 levels increased in a linear fashion over the 4-h infusion period, similar to what was observed in the brain slices, and as in the slices there was no indication of approach to a steady state. However, when given instead as a single-bolus intravenous dose, the striatal [3H]SCH 23390 levels reached a peak only 15 min after injection. Calculations based on the slice experiments, in which the blood-brain barrier is abse...Continue Reading

References

Feb 1, 1992·Neuropharmacology·O InoueT Suzuki
Sep 1, 1992·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·N A Lassen
Jan 1, 1990·European Journal of Nuclear Medicine·G BlomqvistC Halldin
Sep 1, 1990·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·J LoganS J Gatley
Oct 1, 1989·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·L FardeC Halldin
Apr 21, 1986·Life Sciences·P H Andersen, F C Grønvald
Jun 1, 1988·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·D C ChuganiM E Phelps
Jun 15, 1994·European Journal of Pharmacology·C B Farrell, K M O'Boyle
Jan 1, 1993·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·R E CarsonP Herscovitch
Jul 1, 1993·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·J C PriceJ J Frost
Feb 1, 1996·European Journal of Nuclear Medicine·P F KaoR F Dannals

❮ Previous
Next ❯

Citations

May 3, 2005·European Journal of Nuclear Medicine and Molecular Imaging·R M Moresco, F Fazio
Jun 28, 2003·Neurobiology of Aging·Robert M Kessler
May 25, 2011·The Journal of Pharmacology and Experimental Therapeutics·Andrew B NormanRonald W Millard
Mar 21, 2000·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·M Laruelle
Jun 19, 2003·Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology·Ningning GuoAnissa Abi-Dargham
Oct 2, 2013·BioMed Research International·Aage K O AlstrupDoris J Doudet
Apr 30, 2016·British Journal of Pharmacology·Georges Vauquelin
Mar 29, 2002·Molecular Psychiatry·Johannes TauscherS Kapur
May 3, 2016·British Journal of Clinical Pharmacology·Georges Vauquelin
Oct 1, 2010·British Journal of Pharmacology·Georges Vauquelin, Steven J Charlton
Apr 5, 2011·Molecular and Cellular Endocrinology·Heidi DemaegdtGeorges Vauquelin

❮ Previous
Next ❯

Related Concepts

Related Feeds

Blood Brain Barrier Regulation in Health & Disease

The blood brain barrier is essential in regulating the movement of molecules and substances in and out of the brain. Disruption to the blood brain barrier and changes in permeability allow pathogens and inflammatory molecules to cross the barrier and may play a part in the pathogenesis of neurodegenerative disorders. Here is the latest research in this field.

Blood Brain Barrier Chips

The blood brain barrier (BBB) is comprised of endothelial cells that regulate the influx and outflux of plasma concentrations. Lab-on-a-chip devices allow scientists to model diseases and mechanisms such as the passage of therapeutic antibodies across the BBB. Discover the latest research on BBB chips here.

Blood Brain Barrier

The blood brain barrier is a border that separates blood from cerebrospinal fluid. Discover the latest search on this highly selective semipermeable membrane here.