title: Therapeutic 188Re-lanreotide: determination of radiopharmacokinetic parameters in rats.
abstract: OBJECTIVE
  The radiopharmacokinetic parameters of the therapeutic radiopharmaceutical (188)Re-lanreotide were compared in rats implanted with hepatocarcinoma tumours (n= 18) and healthy rats (n= 18).
  
  
  METHODS
  Rats were injected with approximately 1.8 MBq (188)Re-lanreotide (0.1 ml) via the tail vein and blood samples were obtained. The activity per gram of tissue (%IA/g) was calculated and the radiopharmacokinetic parameters determined. Data were fitted using a two-compartment model.
  
  
  RESULTS
  Significant differences were found between healthy and hepatoma rats for beta elimination half-life (22.56 vs 48.14 h); transference constants K(10) (k(e)) (6.44 vs 3.05 h(-1)) and K(12) (2.76 vs 7.09 h(-1)); volume of distribution (2.06 vs 5.45 ml); mean residence time (66.58 vs 95.50 h) and apparent volume of distribution at steady state (131.30 vs 810.37 ml). The tumour/organ ratios after 24 h were 11.20 for tumour/muscle, 8.00 for tumour/liver and 7.72 for tumour/bone. The scintigraphic images obtained therefore had high resolution.
  
  
  CONCLUSIONS
  (188)Re-lanreotide had a prolonged beta elimination half-life and increased volume of distribution in rats with hepatocellular carcinoma. This may be beneficial in the diagnosis and therapy of metastatic lesions in patients with cancer.
authors.affiliation: Departamento de Ingeniería y Tecnología (Biofarmacia), Facultad de Estudios Superiores Cuautitlán, Estado de México, México. mariaeva_molina@yahoo.com.mx
authors.forename: Eva M
authors.initials: EM
authors.lastname: Molina-Trinidad
authors.forename: Consuelo Arteaga
authors.initials: CA
authors.lastname: de Murphy
authors.forename: Helgi
authors.initials: H
authors.lastname: Jung-Cook
authors.forename: Eduardo Murphy
authors.initials: EM
authors.lastname: Stack
authors.forename: Martha
authors.initials: M
authors.lastname: Pedraza-Lopez
authors.forename: José Luis
authors.initials: JL
authors.lastname: Morales-Marquez
authors.forename: Guadalupe Vertiz
authors.initials: GV
authors.lastname: Serrano
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001842:Bone and Bones; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000378:metabolism* / Q000532:radiotherapy; D006207:Half-Life; D008099:Liver; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000378:metabolism* / Q000532:radiotherapy; D008297:Male; D009132:Muscles; D010456:Peptides, Cyclic / Q000493:pharmacokinetics* / Q000627:therapeutic use; D011868:Radioisotopes / Q000493:pharmacokinetics / Q000627:therapeutic use; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics* / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D012211:Rhenium / Q000493:pharmacokinetics* / Q000627:therapeutic use; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D014018:Tissue Distribution
chemical_list: D000970:Antineoplastic Agents; D010456:Peptides, Cyclic; D011868:Radioisotopes; D019275:Radiopharmaceuticals; C060347:lanreotide; D013004:Somatostatin; D012211:Rhenium