THE TOXICITY OF THE SODIUM SALT OF 1,5 DIPHENYLPYRAZOLINE-3-CARBOXYLIC ACID

¹ From the Department of Biochemistry, University of Colorado School of Medicine, Denver, Colorado

1. The toxicity of 1,5 diphenylpyrazoline-3-carboxylic acid for albino rats has been determined. The LD50 for intraperitoneal administration is between 320 and 340 mgm. per kilogram. The LD50 for oral administration is between 500 and 550 mgm. per kilogram.

2. After oral administration of this pyrazoline derivative, the body temperature fall is greater in those animals that die.

3. After administration of the sodium salt of 1,5 diphenylpyrazoline-3-carboxylic acid the urine, frequently the nasal secretions, and after oral administration, the feces, give positive tests for diphenylpyrazoline compounds.

4. A depressive state which roughly parallels the time of body temperature fall follows the administration of this compound.

5. In from 10 to 25 per cent of the rats, when the dose was 300 mgm. per kilogram or greater, convulsions resembling those after morphine administration followed the intraperitoneal injection of the sodium salt of 1,5 diphenylpyrasoline-3-carboxylic acid. Similar convulsions in about the same proportion of the animals followed the oral administration of this compound when the dose was as large as 500 mgm. per kilogram of body weight.

6. Growth curve experiments show that in doses of about of the LD50, given twice weekly, there is no cumulative toxic activity of such a nature that the growth rate in young rats is depressed.