Dose-response changes in organ weights and water contents following rectal administration of toxic doses of acetylsalicylic acid.

Abstract

Most of the significant changes in the mean weight and water content of 18 organs of albino rats at 18 h after the rectal administration of an LD50 of acetylsalicylic acid were found to be dose-dependent. Variations in the dose of drug and in the interval after drug administration selected for measurements were factors which affected the relation between mean changes and close–response correlations. Most mean changes in organ weights and water contents in an acute drug toxicity study will probably be dose–dependent. A dose–response correlation of changes in organ weights and water contents is not necessarily indicated in routine acute toxicity studies on new drugs. Gastric ulcers were found in albino rats 18 h after the rectal administration of 0.8 g of acetylsalicylic acid per kg; and over. It is concluded that measurement of organ weights and water contents in representative groups of animals at death and at intervals in survivors of specified doses of the drug under study will provide probably as much information as the more expensive dose–response studies.