[Thymus structure after polyoxydonium administration]

This investigation was aimed at the evaluation of nature and sequence of thymus structural changes in 25 mice following their treatment with immunomodulating drug, polyoxydonium. Morphometric study has established that the structural reorganization of thymus in mice that was induced by therapeutic doses of polyoxydonium (120 mg per animal once a day for 3 days) had a cyclic course. 4 days after the start of an experiment small increase in the cortical volume was detected. Simultaneously, the surface area, occupied in the sections of the organ by medulla, was found to be significantly decreased in experimental animals. By the end of the first week, there was a decline in a surface area, occupied by the thymic cortex, while afterwards this parameter started to increase, reaching its maximum at 14 days after polyoxydonium treatment. By the end of the experiments (30 days) practically no differences were detected in the areas that were occupied in thymus sections by the cortex and medulla, between the treated animals and those of control groups.