Abstract
Toxins of the gonyautoxin group (GTXs), the major components of paralytic shellfish poison, were isolated from the digestive glands of toxic scallop. No adverse effect of GTXs was observed in male ddY mice pretreated intraperitoneally with GTXs at 2/5 to 3/5 of LD50 for 10 days. This pretreatment did not produce tolerance to a subsequent challenge dose of GTXs as the intraperitoneal LD50 values were 0.760MU/20g for the GTXs-pretreated group and 0.774MU/20g for the control group pretreated with 0.01N hydrochloric acid. Residual toxic efficiency of GTXs was determined by measuring the LD50 for GTXs at intervals of 1, 2, 3 and 4 hours after pretreatment with a single dose of 0.4MU/20g. This efficiency gradually decreased with time and was essentially lost 4 hours after pretreatment.
