PHARMACOKINETICS, ABSORPTION, DISTRIBUTION AND DISPOSITION OF [I]-OLIGOTIDE FOLLOWING INTRAVENOUS OR ORAL ADMINISTRATION IN THE RAT

Oligotide (O) was labelled with ¹²⁵I. The radiolabelled compound (¹²⁵I]-Oligotide (¹²⁵I]-O)) retained the biological activity of parent O. Following single intravenous administration the half lives of radioactivity associated with O and/or O related components in plasma were 9–10 min and 9–10 h for and β phases respectively. Following single oral administration the half life of radioactivity associated with O and/or O related components in plasma was 11.45 – 12.76 h for β fase. Following multiple oral administration once daily for 7 days, the half life of radioactivity associated with O and/or O related components following the 7th dose was 10–12 h for β phase. The areas under plasma total radioactivity versus time curves were dose-dependent. Following single intravenous administration the major proportion of the administered dose was excreted via urine, while following single oral administration excretion via urine and faeces accounted for similar proportions of the administered dose. Following both single and oral administration the levels of radioactive components derived from ¹²⁵I]-O in organs examined were generally highest in highly perfused organs. © 1997 Elsevier Science Ltd