Diterpene Alkaloid
Definition
Aconitine and mesaconitine in Aconitum. Bind site 2 of the voltage-gated sodium channel and prevent inactivation. Refractory ventricular arrhythmia, death within hours.
- Examples
- Aconitine, mesaconitine
- Source plant
- Aconitum
- Mechanism
- Binds site 2 of voltage-gated sodium channel, prevents inactivation
- Clinical course
- Refractory ventricular arrhythmia, death within hours
Common questions
Why is aconitine poisoning particularly hard to treat clinically?+
Because it locks sodium channels open rather than blocking them, the resulting arrhythmias resist standard antiarrhythmic drugs, and treatment is largely supportive while the toxin is metabolised.
How is aconitine poisoning distinguished from other cardiotoxic plant poisons at autopsy?+
Gross findings are nonspecific, so confirmation relies on toxicological identification of aconitine or mesaconitine in blood, gastric contents, or plant material rather than on distinctive pathology alone.
Related terms
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- Cyanogenic Glycoside
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- Keller-Kiliani Test
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- Toxalbumin / Lectin
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- Tropane Alkaloid
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- Vitali-Morin Test
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