Potential and practical adrenomedullary PET radiopharmaceuticals as an alternative to m-iodobenzylguanidine: m-(omega-[18F]fluoroalkyl)benzylguanidines.
To investigate adrenomedullary radiopharmaceuticals for positron emission tomography (PET), we have developed no-carrier-added m-(omega-[18F]fluoroalkyl)benzylguanidines. m-(omega-[18F]Fluoroalkyl)benzylguanidines were prepared in two steps starting from N,N'-bis(tert-butyloxycarbonyl)-N' '-(omega-methanesulfonyloxyalkyl)benzylguanidines in 20-30% radiochemical yields (decay corrected for 100 min) and with high radiochemical purity (>97%) and shown to be stable (>90%) in an in vitro metabolic stability assay. The binding of m-(3-[18F]fluoropropyl)benzylguanidine ((18F]3) to SK-N-SH human neuroblastoma cells was temperature dependent, and binding levels at 4 degrees C were reduced to half of that at 37 degrees C, which was similar to the reduction rate observed for [123I]MIBG. Tissue distribution studies in mice showed the highest uptake in the adrenals (%ID/g = 27.2 +/- 5.0%) with relatively high uptake in the myocardium (%ID/g = 9.3 +/- 0.5%). The results suggest that this radiotracer holds promise as a useful adrenomedullary radiopharmaceutical for PET imaging.
Lee
Byung Chul
BC
Department of Chemistry, Inha University, 253 Yonghyundong Namgu, Inchon 402-751, Korea.
Paik
Jin-Young
JY
Chi
Dae Yoon
DY
Lee
Kyung-Han
KH
Choe
Yearn Seong
YS
D019797:3-Iodobenzylguanidine / Q000737:chemistry* / Q000493:pharmacokinetics; D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000493:pharmacokinetics; D001596:Benzylamines / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D001932:Brain Neoplasms / Q000378:metabolism; D045744:Cell Line, Tumor; D002855:Chromatography, Thin Layer; D003891:Desipramine / Q000493:pharmacokinetics; D005462:Fluorine Radioisotopes; D006146:Guanidines / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D006801:Humans; D066298:In Vitro Techniques; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D051379:Mice; D008813:Mice, Inbred ICR; D008862:Microsomes, Liver / Q000378:metabolism; D009447:Neuroblastoma / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D014018:Tissue Distribution
D000929:Antidepressive Agents, Tricyclic; D001596:Benzylamines; D005462:Fluorine Radioisotopes; D006146:Guanidines; D007202:Indicators and Reagents; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine; D003891:Desipramine