Ultra Violet Rays 



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187 (2147) 



The effect of ultra-violet rays on rats in the circular maze. 

 By DAVID I. MACHT and ELMER J. TEAGARDEN, JR. 



[From the Pharmacological Laboratory, Johns Hopkins University, 



Baltimore, Md.] 



The present research was undertaken in connection with the 

 effect of light on the toxicity of quinine and quinidine sulphates 

 for rats trained in the circular maze. In order to study the 

 effects of the drugs it was essential to learn the effects of ultra 

 violet light itself on the animals. The method employed was 

 the same repeatedly described by Macht and his collaborators in 

 various papers. White rats were trained in the circular maze 

 so as to find their way from the entrance to the center without 

 committing any errors and in the shortest period of time pos- 

 sible. After this preliminary training the animals were exposed 

 to the radiations of the Hanovia Alpine Sun Lamp for periods 

 varying from 10 to 15 minutes or longer and the subsequent 

 behavior of the animals was again studied. 



Six young adult male rats, age about six months, and three 

 old rats, age about one year, were employed. Thirty experi- 

 ments in all were made on the young rats and twenty-four experi- 

 ments on the older animals. A careful analysis of all the data 

 obtained before and after radiation indicated that the effect of 

 ultra violet rays on their behavior in the maze is either negative 

 or more often, slightly stimulating. This stimulating effect was 

 manifested by more rapid muscular activity and persisted for 

 several hours after radiation. All of the animals were found to 

 have resumed their original normal condition within twenty- 

 four hours. It is possible that the increased muscular activity 

 or stimulation is merely the result of irritation, on the other 

 hand no other deleterious effects were produced in the animals, 

 even conjunctivitis occurred only occasionally and was never 

 marked. The general condition of the animals, their nutrition 

 and behavior were not found to be impaired in any way. 



