Introduction to symposium — Brevetoxins: Chemistry and pharmacology of ‘red tide’ toxins from Ptychodiscus brevis (formerly Gymnodinium breve)

Abstract

IN THE last few years extraordinary advances have been made in scientific knowledge of the brevetoxins. After decades of effort to purify the toxic constituents of the Gulf of Mexico `red tide', not .only have the major chemical entities been purified, but their unusually complex structures have been elucidated . During recent years considerable information has been gathered on the cellular mechanisms of action in excitable tissues and on the sites of actions of the toxins in producing their effects on the respiratory and cardiovascular systems in intact organisms. The availability of pure brevetoxins has allowed the molecular mechanism of the effect on excitable mechanisms to be defined in some detail . These scientific advances, as well as the need to stimulate interest in using the basic science information in alleviating the economic and health problems caused by the `red tides', were the underlying reasons for gathering this symposium, which appears to be the first devoted solely to the brevetoxins . There are several pertinent reasons to focus attention on these `red tide' toxins of the Gulf of Mexico and Florida coasts . In addition to the fact that much new chemical and pharmacological information has been gathered in the past few years, the brevetoxin `red tides' produce costly and troublesome fish kills, they cause acute human illness from the ingestion of toxin concentrated by filter feeding shellfish and by producing irritating wind-borne aerosols they make the beach areas invaded by this type of `red tide' intolerable for humans and their animal pets . `Red tide' blooms have been associated with fish kills in the Gulf of Mexico for at least 100 years (WALI~R, 1884). The organism responsible for producing these events was described and named Gymnodinium breve by Davis in 1948 (DAVIS, 1948). A few years ago a more detailed electron microscopic study of this toxin-producing, unarmored dinoflagellate led Steidinger in 1979 to a taxonomic reclassification and renaming of