Cyanofenphos

This protocol assesses in vitro neurotoxicity by combining neuronal viability, mitochondrial/metabolic activity, neurite outgrowth, and optional neuronal network function readouts. Calcein-AM or resazurin/PrestoBlue readouts estimate viable or metabolically active cells; βIII-tubulin immunofluorescence detects neuronal morphology and neurite networks; TMRE detects mitochondrial membrane potential; and MEA recordings detect functional changes in neuronal network activity.

Acute systemic toxicity studies evaluate adverse effects occurring after a single exposure, or repeated exposure within a short acute window, and the main in vivo readouts are mortality, moribund condition, clinical signs, body-weight change, and gross pathological findings; acute oral toxicity methods were developed to replace classical LD50 testing with reduced-animal designs such as fixed-dose procedure, acute toxic class method, and up-and-down procedure. The fixed-dose procedure classifies acute toxicity by administering predefined dose levels and observing evident toxicity rather than using death as the primary endpoint, whereas the acute toxic class method uses sequential groups of three animals per step and the up-and-down procedure doses animals sequentially to estimate an LD50 with fewer animals than conventional LD50 testing.