OMFBiology

biomedicalephemera:

Pitohui variable (now Pitohui kirhocephalus) - The Variable Pitohui
Though all pitohuis have been found to have at least some level of toxin in them, the variable pitohui and hooded pitohui have by far the highest and most consistent levels of it, both in their bodies and throughout their feathers.
The toxins carried by the pitohuis aren’t actually produced by them - like the Columbian poison dart frog, they acquire the toxin from their food sources. Actually, the chemical makeup of their toxin is almost identical to that of the poison dart frogs. They secrete neurotoxic alkaloid compounds known as batrachotoxins. These toxins are lipophilic, and can permeate unbroken skin. They bind to nerve cells, and basically “break” them - they open up the sodium channels in the cells (permanently depolarizing them) so that the nerves can no longer fire, and a flaccid paralysis ensues.
Bizarrely, the tetrodotoxin of the pufferfish may be a possible “treatment” for batrachotoxin-induced paralysis. Tetrodotoxin is non-competitive with batrachotoxin (meaning it wouldn’t be trying to bind to the same part of the cell, and wouldn’t have to remove the batrachotoxin first), and causes an extreme tetanic (stiff) paralysis, because it causes nerve cells to enter a state where they’re permanently firing and can’t stop.
Well, toxin or not, no deaths due to the pitohui have ever been recorded. The Papuan natives see pitohuis as “rubbish birds” because of their toxins, and avoid hunting them. Surely a few natives or explorers have died eating them in the past, but they aren’t an active threat to anyone.
The birds of New Guinea and the adjacent Papuan Islands. R. Bowdler Sharpe and John Gould, 1875-1888.

Pitohui variable (now Pitohui kirhocephalus) - The Variable Pitohui

Though all pitohuis have been found to have at least some level of toxin in them, the variable pitohui and hooded pitohui have by far the highest and most consistent levels of it, both in their bodies and throughout their feathers.

The toxins carried by the pitohuis aren’t actually produced by them - like the Columbian poison dart frog, they acquire the toxin from their food sources. Actually, the chemical makeup of their toxin is almost identical to that of the poison dart frogs. They secrete neurotoxic alkaloid compounds known as batrachotoxins. These toxins are lipophilic, and can permeate unbroken skin. They bind to nerve cells, and basically “break” them - they open up the sodium channels in the cells (permanently depolarizing them) so that the nerves can no longer fire, and a flaccid paralysis ensues.

Bizarrely, the tetrodotoxin of the pufferfish may be a possible “treatment” for batrachotoxin-induced paralysis. Tetrodotoxin is non-competitive with batrachotoxin (meaning it wouldn’t be trying to bind to the same part of the cell, and wouldn’t have to remove the batrachotoxin first), and causes an extreme tetanic (stiff) paralysis, because it causes nerve cells to enter a state where they’re permanently firing and can’t stop.

Well, toxin or not, no deaths due to the pitohui have ever been recorded. The Papuan natives see pitohuis as “rubbish birds” because of their toxins, and avoid hunting them. Surely a few natives or explorers have died eating them in the past, but they aren’t an active threat to anyone.

The birds of New Guinea and the adjacent Papuan Islands. R. Bowdler Sharpe and John Gould, 1875-1888.

Source: biomedicalephemera