Isolation of eburnetoxin, a vasoactive substance from the Conus eburneus venom

Eburnetoxin, a powerful vasoactive protein has been isolated from the venom of the marine snail Conus eburneus, monitored by the contractile effect to the rabbit aorta. The molecular weight was estimated to be 28,000 by gel permeation chromatography and slab gel electrophoresis. The purified protein was electrophoretically homogeneous. The toxin at concentrations above 3 X 10(-7) g/ml elicited a marked contractile response of aorta, which was inhibited by verapamil (10(-6) M). The minimum lethal dose in the fish Rhodeus ocellatus smithi was 1 microgram/g body weight.