Blue-ringed Octopus Research Articles

Chemistry of maculotoxin: A potent neurotoxin isolated from Hapalochlaena maculosa

The toxin from Hapalochlaena maculosa (the blue-ringed octopus) has been isolated in a chromatographically pure state. The toxin (maculotoxin) is a stable, highly polar compound, having a relatively low molecular weight. Maculotoxin behaves as a cation under certain conditions and was shown to be chemically similar to, but distinct from, tetrodotoxin.

Octopus neurotoxins: Low molecular weight non-immunogenic toxins present in the saliva of the blue-ringed octopus

Octopus neurotoxins: Low molecular weight non-immunogenic toxins present in the saliva of the blue-ringed octopus

Maculotoxin, a potent toxin secreted by Octopus maculosus Hoyle

The posterior salivary (venom) glands of the blue-ringed octopus, Octopus (Hapalochlaena) maculosus Hoyle have been shown to contain a neurotoxin which is pharmacologically very similar to tetrodotoxin and saxitoxin. The toxin, which has been called “maculotoxin,” causes hypotension, bradycardia, and respiratory paralysis in rabbits and rats. The hypotension can be temporarily reversed with l-epinephrine or l-norepinephrine. Evidence is presented which suggests that respiratory failure after intravenous injection is due to blockade of muscular nerve axons. The toxin blocks transmission in the sciatic nerve of the toad and the rat, and at low dose levels appears to have neuromuscular blocking activity. At higher dose levels the muscle membrane also becomes inexcitable. It is without significant effect on the acetylcholine-induced contraction of the chronically denervated rat diaphragm, the toad rectus abdominis, or the guinea pig ileum. Animals can be resuscitated after a marginal lethal dose by artificial ventilation alone, provided this is instituted before hypoxia becomes severe.