Pathologic Changes in the Brain from 

 Exposure to Alpha Particles from a 60 Inch 



Cyclotron * 



Peter Janssen, *■* 



Dormer Laboratory, Unirersity of California, Berkeley, California, 

 Armed Forces Institute of Pathology, ]\'ashington, D.C. 



Igor Klatzo, Jaime Miquel, 



National Institute of Neurological Diseases and Blindness, 

 National Institutes of Health. Bethesda, Maryland 



Tor Brustad, 



Norwegian Radium Hospital, Oslo, Norway 



Albert Behar, Webb Haymaker,*** 



Armed Forces Institute of Pathology. Washington, D.C. 



John L^man. Jilian Henry, and CIornelius Tobias 



Donner Laboratory, University of California, Berkeley, California 



Introduction 



This paper deals chiefly with time-dose relationships in the appearance 

 of alterations in the cerebellum and cerebrum of rats followin" exposure to 

 alpha particle radiation from the 60 in. cyclotron in Berkeley. Exposure 

 of brains to protons was also done for comparison. We were concerned with 

 ( 1 ) severity of the lesions in terms of energy given off along the course of 

 the Bragg cin\e, (2) alterations in structural elements with respect to time- 

 dose relationships, and ( 3 ) circulatory and vascular alterations, including 

 permeability changes as assessed by the Pickworth-Lepehne stain for erythro- 

 cytes and by certain fluorescence indicators, i.e., fluorescein-labeled scrimi 

 proteins (FLSP) and sodium fluorescein. 



Methods 



In earlier phases of the study with about 25 ''r of the animals, the top of 

 the skull was removed (in a 15 x 10 mm area) and the dura left intact 



* This sUidy was supported by funds from the U.S. Atomic Energy Commission and 

 the National Aeronautics and Space .Administration. 



** Present .Address: Institut Neurologique Beige, Brussels. Belgium. 



*** Present .Address: N.AS.A .Ames Research Center. MoflFett Field. California. 



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