Alteration of Mammalian Nerve Compound 

 Action Potentials by Beta Irradiation 



Edgar L. Gasteiger 



University of Rochester 



School of Medicine and Dentistry 



Rochester, New York 



AND 



Berry Campbell 



College of Medical Evangelists, 

 Los Angeles, California 



Introduction 



In an earlier work (Gasteiger, 1959) the radioresistivity to beta irradi- 

 ation of fast A fibers of cutaneous nerves was reported, with a review of 

 other closely related research. In nearly all studies the assays have been 

 made on large A fibers. Aside from an earlier summary (Gasteiger, 1951) 

 of the work reported here, only Gerstner (1956) has published observations 

 on the comparative sensitivity of other fiber types to ionizing radiations. 



Although it is important to accumulate infoiTnation on the response of 

 various nerve types to radiations, the interpretation of the relative sensi- 

 tivities is, to a large degree, lost in our limited knowledge of mechanism 

 and structure of the smaller fibers. Since, in a few cases, irradiation of 

 patients reaches veiy high levels in a small field, and irradiation neuritis 

 does result, investigation of differential sensitivity may be of definite prac- 

 tical importance. Also, with the increasing number of irradiation studies of 

 the central nervous system, a knowledge of the relative sensitivity of fiber 

 types becomes essential for interpretation of experimental observations. 



Methods 



A total of 43 experiments were performed on sural, saphenous, and vagal 

 nerves removed from 18 Dial-anesthetized cats and placed in a commercial 

 Simms solution at room temperature until needed. Before transferring a 



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