Danomycin**, a new antibiotic active against Gram-positive bacteria, especially staphylococci, was isolated from the culture filtrate of Streptomyces albaduncus¹⁾ which is a new strain of streptomycetes. Since the antibiotic was highly active in vivo against experimental infections in mice¹⁾, studies were undertaken on the pharmacology of danomycin prior to clinical investigation. The following toxicological, pharmacological and histopathological studies were therefore made:

I. Acute toxicity

II. Chronic toxicity

A. Effect on the growth of rats

B. Observation of organs at autopsy

C. Microscopic observation

III. Effect on kidney and liver functions

VI. Local action

V. Hematological effects in rabbits

A. Single administration

B. Daily administration

VI. Absorption and excretion

VII. Tissue distribution

VIII. Effect on the cardiovascular system

A. Effect on respiration and blood pressure

B. Effect on the isolated heart of rabbit

C. Effect on peripheral blood vessels

IX. Effect on smooth muscle

A. Effect on the isolated intestine of rabbit

B. Effect on the isolated uterus of rabbit

X. Effect on cholinesterase and monoamine oxidase