Biological Activity
The Dendrobatidae family of poison-dart frogs has yielded many different alkaloids categorized into several different classes, almost all of which have shown high pharmacological activity on muscle and nerve cells.
The pumiliotoxin-A class, specifically, contains many molecules which have had a favorable effect on the heart. Allopumiliotoxins, the most complex member of this class, have a wide range of biological activities, the full understanding of which has not been fully discerned due their incredible complexity and subsequent synthetic difficulties. Among allopumiliotoxins, those with a β-oriented C-7 hydroxyl group have shown greater activity in comparison to α-epimers of this position. Allopumiliotoxin 339A has been shown to stimulate sodium influx and phosphoinositide breakdown in the cerebral cortical synaptoneurosomes of guinea pigs and is one of the most active allopumiliotoxins. It is more biologically active than pumiliotoxin B, which has had similar biological affects on the secondary messenger system, causing muscle rigidity and some favorable effects on the heart.
Pumiliotoxins and allopumiliotoxins are very toxic in general. Pumiliotoxin B has caused death in mice when 20 μg was given in injections below the skin
Read more about this topic: Allopumiliotoxin
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