{Reference Type}: Journal Article
{Title}: Sigma-1 Agonist Binding in the Aging Rat Brain: a MicroPET Study with [(11)C]SA4503.
{Author}: Ramakrishnan NK;Visser AK;Rybczynska AA;Nyakas CJ;Luiten PG;Kwizera C;Sijbesma JW;Elsinga PH;Ishiwata K;Dierckx RA;van Waarde A;
{Journal}: Mol Imaging Biol
{Volume}: 18
{Issue}: 4
{Year}: 08 2016
{Factor}: 3.484
{DOI}: 10.1007/s11307-015-0917-6
{Abstract}: Sigma-1 receptor ligands modulate the release of several neurotransmitters and intracellular calcium signaling. We examined the binding of a radiolabeled sigma-1 agonist in the aging rat brain with positron emission tomography (PET).<BR>Time-dependent uptake of [(11)C]SA4503 was measured in the brain of young (1.5 to 3 months) and aged (18 to 32 months) Wistar Hannover rats, and tracer-kinetic models were fitted to this data, using metabolite-corrected plasma radioactivity as input function.<BR>In aged animals, the injected probe was less rapidly metabolized and cleared. Logan graphical analysis and a 2-tissue compartment model (2-TCM) fit indicated changes of total distribution volume (V T) and binding potential (BP ND) of the tracer. BP ND was reduced particularly in the (hypo)thalamus, pons, and medulla.<BR>Some areas showed reductions of ligand binding with aging whereas binding in other areas (cortex) was not significantly affected.