Cardiac Glycoside
Definition
A steroidal compound that inhibits the sodium-potassium ATPase pump in cardiac myocytes, raising intracellular calcium and producing bradyarrhythmia, AV block and hyperkalaemia. Cerberin (Cerbera odollam), oleandrin (Nerium oleander) and digoxin (Digitalis) belong to this class.
- Chemical structure
- Steroidal compound (cardenolide) bound to sugar
- Primary target
- Sodium-potassium ATPase pump in cardiac myocytes
- Main cardiac effects
- Bradyarrhythmia, AV block, hyperkalaemia
- Common forensic sources
- Oleander, yellow oleander, foxglove (Digitalis)
Common questions
What do cardiac glycosides actually do inside the heart?+
They block the sodium-potassium pump (Na+/K+-ATPase) on heart muscle cells, which causes calcium to build up inside. This triggers irregular heartbeats, slowed conduction between the heart's chambers, and dangerous potassium levels in the blood.
Which plants have cardiac glycosides?+
Oleander (Nerium oleander), yellow oleander (Cerbera odollam), and foxglove (Digitalis) are the main forensic sources. Their active compounds include oleandrin, cerberin, and digoxin respectively.
Why do cardiac glycosides cause dangerous potassium levels?+
When the Na+/K+-ATPase pump is blocked, cells can no longer pump potassium out properly, so potassium accumulates in the bloodstream instead of staying inside cells. This causes hyperkalaemia, which disrupts the heart's electrical rhythm.
Related terms
- Tropane Alkaloid
- A class of bicyclic nitrogen-containing alkaloids (atropine, hyoscyamine, scopolamine) produced by Solanaceae such as Datura and Atropa belladonna. Acts as a competitive...
- Anticholinergic Syndrome
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- Arylnaphthalide Lignan
- A plant secondary metabolite class to which the cleistanthins (Cleistanthus collinus toxins) belong. The cleistanthins damage the distal renal tubule, producing a...
- Cyanogenic Glycoside
- Sugar-cyanide conjugate (amygdalin in bitter almonds, linamarin in cassava). Hydrolysis releases HCN, which inhibits cytochrome c oxidase.
- Diterpene Alkaloid
- Aconitine and mesaconitine in Aconitum. Bind site 2 of the voltage-gated sodium channel and prevent inactivation. Refractory ventricular arrhythmia, death within hours.
- DNA Barcoding
- Species identification using a short, standardised region of the mitochondrial genome. For animals, the primary barcode marker is a 648-base-pair segment of...
- Keller-Kiliani Test
- Cardiac-glycoside test. Glacial acetic acid + FeCl3 layered with H2SO4 gives a reddish-brown ring and blue-green upper layer for 2-deoxysugars.
- Ribosome-Inactivating Protein (RIP)
- A glycoprotein toxin that enzymatically depurinates 28S rRNA and shuts down protein synthesis. Abrin (Abrus precatorius) and ricin (Ricinus communis) are type...
- Shodhana
- The traditional ayurvedic purification process applied to aconite root and a few other toxic plant materials before therapeutic use. Boiling in cow's...
- Toxalbumin / Lectin
- Two-chain plant protein (A-chain catalytic, B-chain lectin) that depurinates a specific adenine in 28S rRNA, inactivating the 60S ribosomal subunit. Abrin and...
- Vitali-Morin Test
- Tropane-alkaloid colour test. Fuming HNO3, evaporate, then alcoholic KOH gives violet with atropine and hyoscyamine. Negative on cocaine.
Explained in these topics
- Plant Poisons: Abrus, Ricinus, Datura, Aconite and OleanderCardenolide plus sugar. Oleandrin and thevetin inhibit Na+/K+-ATPase, raising intracellular calcium and producing bradyarrhythmia and hyperkalaemia.
- Plant Poisons of Medico-Legal Importance in IndiaA steroidal compound that inhibits the sodium-potassium ATPase pump in cardiac myocytes, raising intracellular calcium and producing bradyarrhythmia, AV block...