BIOLOGICAL EVALUATION OF 2 IODINE-123-LABELED D-GLUCOSE ACETALS PREPARED AS GLUCOSE-TRANSPORTER RADIOLIGANDS

Two iodinated acetals of D-glucose, 4,6-(R)-O-(2'-iodoethylidene)-alph a, beta-D-glucose (1) and 4,6-(R) O-(4'-iodobenzylidene)-alpha, beta-D -glucose (2), were prepared and their potential as suitable SPECT radi oligands for imaging of glucose transporters was studied. Both are ana logs of acetal D-glucose derivatives, which are known to bind to the e xofacial sites of the glucose transport protein (GluT). To assess whet her iodinated acetals 1 and 2 interacted with the glucose transporter, they were tested in vitro in human erythrocytes (GluT1) and neonatal rat cardiomyocytes (GluT4). The results indicated that 1 and 2 had a v ery low affinity for the glucose transporter and probably accumulated in cells. Study of their tissue distribution was carried out in the mo use in vivo: Both compounds showed fast tissue clearance with preferen tial renal elimination. It is concluded that iodinated acetals of D-gl ucose 1 and 2 are not suitable for GluT targeting in vivo. NUCL MED BI OL 255:473-480, 1998. (C) 1998 Elsevier Science Inc.