Localization of Radioisotope (Chlormerodrin Hg-203) in Experimental Cerebral Infarction

A combined histological and radioautographical study was made to determine the mechanism for the selective localization of Hg-203-labelled Chlormerodrin in the brain of 13 cats with experimentally induced cerebral infarction. The presence of the radioactive tracer in the infarcted areas was noted within a few days after the onset of the lesions and was increased by hemorrhage into the tissues. The radioautograms revealed the radioactive material to be localized mostly within macrophages and in areas surrounding capillary proliferation. These two pathoanatomic processes associated with necrosis of the cerebral tissues most likely account for the abnormal accumulation of radionuclide tracer in brain scans of patients with cerebral infarction.