3-Nitropropionic acid (3-NP) is an irreversible inhibitor of mitochondrial respiratory Complex II succinate dehydrogenase, resulting in energy depletion through disruption of the electron transport chain. This compound is a natural toxin of certain plants and fungi. Administration of 3-NP to rats (12 mg/kg per day) produces progressive striatal degeneration, while lower doses (8 mg/kg daily) in nonhuman primates results in neuropathologic and clinical features of Huntington’s disease. Conversely, Huntington’s disease results in a loss of Complex II activity. 3-NP also induces convulsions and is used to examine interventions effective in a mouse model of epilepsy.
