phosphorus-radioisotopes and defibrotide

Defibrotide (D) was labelled with 125I or with 32P. The radiolabelled compounds ([125I]-Defibrotide ([125I]-D), [32P]-Defibrotide ([32P]-D) retained the same profibrinolytic activity, in vitro, as the parent drug, suggesting that the labelling procedures had not modified the pharmacological properties of D and hence that its chemical structure was not affected significantly. After single intravenous or oral administration of [125I]-D or [32P]-D the pharmacokinetic parameters for the two labels were generally in good agreement (75%). t 1/2 alpha was in the range of minutes while t 1/2 beta was in the range of hours. Bioavailability, following single oral administration of [125I]-D or [32P]-D, was in the range of 58-70%. These data suggest that D, in spite of its macromolecular nature, is absorbed, after oral administration, fairly well.

Topics: Administration, Oral; Animals; Biological Availability; Fibrinolysis; Fibrinolytic Agents; Half-Life; Injections, Intravenous; Iodine Radioisotopes; Male; Phosphorus Radioisotopes; Polydeoxyribonucleotides; Rats; Rats, Sprague-Dawley