Abstract: OBJECTIVE:To establish a method for the biotoxicity detection of paralytic shellfish toxins. METHODS:Cultured mouse neural stem cells (NSC) were exposed to ubunin,resveratrol and different concentrations of standard solution of clam toxins. The in vitro detection method was established based on evaluation of the dose-response relationship between the content of standard liquid and D(450) value of the clams. RESULTS:In culture,the normal NSC started as single cell suspensions which formed small neurospheres in 2-3 days and large neurospheres in the fourth day. After adding ouabain and cucurbitine,the cells showed swelling and rupture. After adding STX,the cells became swollen or ruptured but the cell morphology was mostly normal. Consequently,the in vitro biotoxicity detection of paralytic shellfish toxins was established within the range of 0.2-1.0 ng and a standard curve was established. The regression equation was:y=1.252+0.495x (r=0.998 0,P < 0.01). CONCLUSION:An in vitro method for the biotoxicity detection of paralytic shellfish toxin was successfully established. The method can be further developed for in vitro detection of neurotoxins.

Key words: paralytic shellfish poisoning, mouse neural stem cells, in vitro detection method, ubenoside, veratrine