Antituberculous Activity and Toxicity of Lupulon for the Mouse. *

Summary

Lupulon, a fat-soluble antibiotic derived from hops, has relatively low in vitro activity (1:40,000) as compared with other antituberculous agents. Despite this observation, lupulon (given orally or intramuscularly) was active against experimental mouse infections of M. tuberculosis. Following intramuscular administration, significantly lower numbers of acid-fast organisms occurred in lesions of treated animals. The approximate numbers relative to the control were: In the liver, 34 to 1; heart, 8 to 1; spleen, 4 to 1; and lungs, 4 to 1; but not in the kidneys. In orally treated animals the ratios were: Liver, 10 to 1; heart, 3 to 1; spleen, 10 to 1; lungs, 5 to 1, and kidneys, 2 to 1. The over-all difference was a reduction of approximately 4 to 1 by either route of administration.

Lupulon given intramuscularly within its effective range produced some foci of degeneration in renal tubules. Such pathologic changes were not observed in infected animals given this antibiotic orally in effective doses. The single LD₅₀ on intramuscular administration was 600 mg per kilo in mice; on oral application, 1,500 mg per kilo.