Effect of Cocaine on Lupinus alba. 235 



xanthin is very slightly soluble nevertheless even very minute 

 quantities of the substance (1 c.c. of 1-200,000 solution) introduced 

 into 25 c.c. of Locke's solutions in which the preparation was 

 suspended were found to produce a very marked relaxation. 

 Hypoxanthin acted in the same way. Going a step further 

 experiments were made with minute quantities of guanidin and 

 adenin and both of these were found to produce relaxation of the 

 bronchus and seemed to be comparatively more potent even than 

 xanthin. Passing to the nucleosid guanosin, the pharmacological 

 action became different. Guanosin produced no effect. A few 

 experiments with adenin nucleotid showed that it also was in- 

 active. Finally tests made with solutions of thymus nucleic acid 

 and yeast nucleic acid gave also no effect on the bronchial muscle. 



102 (1849) 



Effect of cocaine on the growth of lupinus alba : a contribution to 

 "phy topharmacology . * ' 



By DAVID I. MACHT and MARGUERITE LIVINGSTON 



[From the Pharmacological and Plant Physiology Laboratories, Johns 

 Hopkins University, Baltimore, Md.} 



The effects of cocaine and its decomposition products were 

 studied on the growth of seedlings of the plant Lupinus alba. The 

 seeds were soaked in water and allowed to sprout in a suitable 

 medium, following which the length of the straight roots grown 

 by this plant was measured and the effects of cocaine and other 

 chemicals on the growth of the roots were investigated. The 

 plants were placed in solutions of nutrient salts (Shive solution) 

 and the various drugs were added to such solutions. Controls 

 were made on seedlings suspended in Shive solution diluted one 

 half with distilled water. It was found that the effect of cocaine 

 and its decomposition products on the growth of lupinus was very 

 different from the effect of the same substances on animal tissues. 

 Whereas cocaine is very toxic for animal tissues such as smooth 

 and skeletal muscle, nerves, etc., it required strong solutions of 

 this alkaloid, namely 2 per cent, of cocaine hydrochloride to inhibit 



