Early changes induced in purkinje cells of rabbit by single massive doses of roentgen rays.

That nerve tissue is highly resistant to Roentgen radiation is well known through reports in the literature indicating that large repetitive doses will induce pathological changes in the nerve cells both in man1 and in laboratory animals.2, 3 Time correlation of these changes has not been made in most of the reported studies. The present investigations were designed to clarify this matter by utilizing single massive exposures which serve as a starting point in relating histological change with elapsed time.Twenty-five rabbits, 4 to 5 lb in weight, were irradiated in 4 groups of 6 and one singly. With the aid of a special holder, the heads of the animals were held in place in a circle of small radius and simultaneously irradiated. The dosage is listed in Table I.The changes observed in the treated animals were chromatolysis, vacuolization of the cytoplasm, pyknosis, and loss of cells through neuronophagia. The animals killed immediately following irradiation showed marked lysis of the Nissl material of the...