Curarizing effect of neomycin and its fractions in the frog.

SummaryCommercial neomycin and its fractions A, B and C possess a curarimimetic action as found when employing sciatic-gastrocnemius preparation of frogs. This action is more pronounced with commercial neomycin and fraction B than with fractions A (Neamine) and C. The blockade induced by neomycin, fraction B and C, but not by fraction A. was effectively antagonized with neostigmine or edrophonium in proper doses. Ether anesthesia did not potentiate this action in the frog when neomycin or its fractions B and C were used.