Effects of High-Dose Gamma Radiation on 

 the Brain and on Individual Neurons* 



F. Stephen Vogel 



Nezr York Hospital — Cornell University Medical Center, 

 Xeiv York, Xe;c York 



Massive doses of ionizins, radiation reoularly and promptly brina; about 

 characteristic morpholosic alterations in certain neural tissues and in the 

 mesenchymal structures in and around the brain (Arnold et al., 1954; Hay- 

 maker <'^ al, 1958; Voa;el ct al., 1958: Wilson, 1960). Most notable among 

 these chanoes are contraction and pyknosis of the nuclei of the granule 

 cells of the cerebellum and leiicocytic infiltration into the walls of the 

 cerebral blood vessels, in the leptomeninges, and choroid plexuses. These 

 were conspicuous in monkeys exposed to large doses of gamma radiation 

 from Ba""-La^^" and Co''" sources, as have been described elsewhere 

 (Haymaker ct al.. 1958; Vogel rt al., 1958). 



There is much e\ idence that the pyknotic change in the cerebellar granule 

 cells in cats i Briinner. 1920), monkeys Vogel ft al., 1958), rabbits 

 (Gerstner ct al., 1956), guinea pigs ( AKord and Brace, 1957), mice, and 

 rats (Hicks and Wright, 1954) is transitory, and ancillary studies indicate 

 that similar transient structural changes occur in these cells grown in tissue 

 culture and exposed to ionizing radiation. Ne\ertheless, recent observations 

 have made it clear that in dogs this cellular response, although initially 

 characterized by nuclear contraction, is often followed promptly by karyor- 

 rhexis with cellular death (Vogel, 1959 i. When examined with the electron 

 microscope, the pyknotic and kaiyorrhetic cells regularly show distinctive 

 alterations in intracellular fine structure i Vogel, 1959). These pro\ide in- 



* These studies were conducted at the Uni\ersity of California. .-Xrmed Forces 

 Institute of Pathology, Washington, D.C., Randolph .\ir Force Base. Randolph Field, 

 Texas, and at the University of Texas and the U.S. .\ir Force, Austin, Texas. They 

 were supported by funds provided by the U.S..\.F. School of .Aviation Medicine, Ran- 

 dolph .\ir Force Base. Texas, by the Medical Research and Development Board, Office 

 of the Surgeon General, U.S. .\rmy. and by a research grant from the National Insti- 

 tute of Neurological Disease and Blindness of the National Institutes of Health, U. S. 

 Public Health Ser\ice. 



The technical assistance of Mrs. Margarete Markey in preparing the tissue cultures 

 is gratefully acknowledged. 



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