产品介绍： Saxitoxin (STX) is a neurotoxin that acts as a selective sodium channel blocker and is naturally produced by certain species of marine dinoflagellates (Alexandrium sp., Gymnodinium sp., Pyrodinium sp.) and cyanobacteria (Anabaena sp., some Aphanizomenon spp., Cylindrospermopsis sp., Lyngbya sp., Planktothrix sp.). Ingestion of STX (usually through shellfish contaminated by toxic algal blooms) is responsible for the human illness known as paralytic shellfish poisoning (PSP). Saxitoxin, one of the most potent natural toxins known, acts on the voltage-gated sodium channels of nerve cells, preventing normal cellular function and leading to paralysis.