Scintigraphic imaging with 99mTc- exorphin C in rabbits.
Exorphin C is a peptide with five amino acids [(Tyr-Pro-Ile-Ser-Leu) Trifluoroacetate salt] (Sigma) that has an affinity to opioid receptor-expressing tissues and tumors. Exorphin-C was labeled with 99mTc using glucoheptonate (GH) as bifunctional chelating agent. Then, we investigated its radiopharmaceutical potential as opioid receptor-expressing tissue on rabbits. Quality controls were performed by ITLC, paper electrophoresis and HPLC. Labeling efficiency was higher than 98%. The compound was stable for at least 5 h at room temperature. Scintigraphic imaging with 99mTc-GH-exorphin C (99mTc-GE) was performed on male Albino rabbits. Static images were obtained from anterior projection using a Camstar XR/T gamma camera at several time intervals. Although a significant amount of activity was seen in the brain, less activity was seen on receptor saturation studies at 30 min. Slight hepatobiliary excretion was seen, though the main excretion route was renal. After saturating, the receptor hepatobiliary excretion was not seen; the only excretion route was renal.
Ertay
T
T
Department of Nuclear Medicine, Medical School, Dokuz Eylül University, Inciralti, Turkey. turkan.ertay@deu.edu.tr
Unak
P
P
Tasci
C
C
Zihnioğlu
F
F
Durak
H
H
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004590:Electrophoresis, Paper; D008297:Male; D015609:Organotechnetium Compounds; D010455:Peptides; D011817:Rabbits; D011877:Radionuclide Imaging
D015609:Organotechnetium Compounds; D010455:Peptides; C019178:exorphins