Cowboys and Cowgirls

[AKvetch]

Table centerpiece from Oleander? Uhhh, you do realize oleander is poisonous?

The toxic cardenolide oleandrin contained in the Oleander plant has its effect on the heart and, indirectly, the central nervous system vagal nerve.The oleandrin glycoside has been found to inhibit the plasmalemma Na+,K+ ATPase. The inhibition of this pump leads to increased intracellular sodium concentrations, increased calcium levels, and subsequently affects the force of heart contractions by lowering excitability and a poisoning of the heart cells (Jortani 1657). The oleandrin also decreases the rate of sino-atrial node depolarization by increasing vagal tone because of a blocking of the nerve conduction (Laborde 5).This action is like that of digitalis glycosides that are known to be CNS depressants.

The toxicity of the oleandrin varies between body size and age of humans and differs also between animal species.A handful of leaves of oleander will make an adult human sick, but not kill him.Where one leaf is enough to quickly kill a small child.(Laborde 5,6)It seems that for most livestock animals 0.005% to 0.015% of the animalÌs body weight in green oleander leaves has proven to be fatal.(Monroe3,4,6)However high these amounts may seem, the IC50 amounts of oleandrin are much lower than that of digoxin in the body.This is due to the fact that oleandrin binds to a much higher amount of protein in the plasma and therefore is less available to act as a toxin.Yet, the oleandrin is more cytotoxic than the studies compared with digoxin (Jortani 1657).

For the complete article, including symptoms and treatment, see:

http://chemweb.calpoly.edu/chem/bailey/377/PapersSp2000/Sarah/