Fang blennies — the tiny fish found in reef areas — have surprised scientists with their unique, heroin-like venom used in repulsing predators. The composition, mode of delivery and range of applications of the venom have become promising areas of study.
According to a new research, what makes It peculiar is the way the small fish takes on predators by injecting their jaws with venom that is loaded with opium-derived substances.
The fang blennies do not use venom for capturing prey but uses it as a means of defense to escape predators by giving them a heroin-like high.
Fang blennies are the preferred fish for home aquariums. Being small, they become an easy target for predators who try to gobble them up. When any predator tries to eat up this tiny fish, fang blennies retaliate by sinking their powerful canines into the predator's jaw and escape the grip unruffled.
"This study showed that the venom delivery system, the big fangs, evolved before the venom did," said study author Nicholas Casewell from the Liverpool School of Tropical Medicine.
No Pain But Sedation From Fang Blennies Venom
Normally, a venomous fish bite will be highly painful. It has been estimated that there are some 2,500 poisonous fishes and they deliver venom through fins or tails.
The venom of fang blennies is different as fang blenny is one of the two fish species that injects venom by biting the attacker just as a snake does.
In the case of fang blenny, the venom causes no pain as it contains opioid hormones and acts like painkillers.
"Its venom is chemically unique. The fish injects other fish with opioid peptides that act like heroin or morphine, inhibiting pain rather than causing it," said co-lead researcher Brian Fry from the University of Queensland in Australia.
Among related studies, the most notable was the one conducted by George Losey in 1972 who even conducted tests of the venom on mice and himself.
"The toxicity of the bite of Meiacanthus atrodorsalis was assayed by force-biting the tails of two white laboratory mice and my hand," Losey wrote in his study.
The new study mainly focuses on how the venom actually works.
Scope For Applications In Pharmaceuticals
The new study presumes that a drop in blood pressure on the predators when fang benny gives a sting and have been revealed by researchers.
The findings have been published in Current Biology.
"For the fang blenny venom to be painless in mice was quite a surprise," noted Fry.
When a sudden drop in blood pressure hits the predator, the attacker gets disorientated and fails to give a chase.
"By slowing down potential predators, the fang blennies have a chance to escape," said Fry.
The proteomic analysis of fang blenny venom showed three components — a neuropeptide as in cone snail venom, lipase as in scorpions, and an opioid peptide.
When blenny venom was injected into lab mice, the mice had no signs of pain.
"Fish with venomous dorsal spines produce immediate and blinding pain," said Fry.
Now scientists are hoping that more research into fish venom and the chemicals in it could be useful in developing applications for pharmaceuticals. The research hogs credit for shining a fresh spotlight on fish venom in general.
