title: Technetium-99m bis (aminoethanethiol) complexes with amine sidechains--potential brain perfusion imaging agents for SPECT.
abstract: In an effort to develop new clinically useful technetium-99m bis(aminoethanethiol) ([99mTc]BAT) complexes for the evaluation of regional cerebral perfusion, two new BAT ligands containing amines in the sidechain were synthesized and subsequently complexed with 99mTc to yield the target complexes: [99mTc]DEA and [99mTc]TMPDA. Each complex was obtained as mixtures of two isomers, syn and anti, which were separated chromatographically. In biodistribution studies, both isomers of [99mTc]TMPDA showed little uptake in the brain. In contrast, the brain uptake values at 2 and 15 min for [99mTc]DEA-anti were 0.99 and 0.26, whereas, the corresponding values for DEA-syn were 2.27, 0.64% dose/organ, respectively. Autoradiographic studies (in rats) using both isomers of [99mTc]DEA show a fixed regional distribution and a higher concentration of radioactivity in the gray matter relative to the white matter. Planar imaging using [99mTc]DEA-syn clearly demonstrates localization of the complex in the brain with a T 1/2 of 41 min, suggesting some potential for use with single photon emission computed tomography.
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging* / Q000502:physiology; D002560:Cerebrovascular Circulation; D003543:Cysteamine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism; D000882:Haplorhini; D007553:Isotope Labeling; D008297:Male; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000378:metabolism; D015609:Organotechnetium Compounds; D051381:Rats; D011919:Rats, Inbred Strains; D013667:Technetium / Q000378:metabolism; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed
chemical_list: D009942:Organometallic Compounds; D015609:Organotechnetium Compounds; C052664:technetium Tc 99m TMPDA; C052663:technetium Tc 99m DEA; D003543:Cysteamine; D013667:Technetium