Assessment of the effect of vincristine on the biodistribution of Tc-99(m)-labelled glucoheptonic acid in female Balb/c mice

There is evidence that the biodistribution and the pharmacokinetics of Tc-9 9(m) radiopharmaceuticals can be modified by some drugs, pathological state s, irradiation and surgical procedures. Vincristine have been widely used i n various chemotherapeutic protocols in oncology. We are trying to develop an animal model to assess the toxicology in different organs of compounds u sed as therapeutic drugs. We have studied the effect of vincristine on the distribution of Tc-99(m)-glucoheptonic acid (Tc-99(m)-GHA) in female mice. After the last dose of vincristine, Tc-99(m)-GHA (7.4 MBq) was injected, th e animals sacrificed and the percentage of radioactivity determined in the isolated organs. The percentage of activity was significantly decreased in the uterus, ovary, spleen, thymus, lymph nodes (inguinal and mesenteric), k idney and heart, but was not significantly altered in the lung, liver, panc reas, stomach, thyroid, brain and bone. Our results can be explained by the metabolic, toxic, therapeutic and immunosuppressive actions of this chemot herapeutic drug. ((C) 2000 Lippincott Williams & Wilkins).