PAIN KILLERS come in all shapes and sizes but few as unexpected as a 10ft-long snake. Forget your aspirins and paracetamols, scientists have discovered a substance in snake venom that can block pain as effectively as morphine.
And this is no ordinary snake. The black mamba is considered the world’s deadliest and its bite can kill in as little as 20 minutes.
Yet the venom also contains a powerful pain blocker as strong as opiate drugs but without the negative side-effects. The finding opens up the potential to develop new kinds of analgesics able to block the nerves that handle pain, say the French research team who publish their findings this morning in the journal Nature.
The black mamba has a fearsome reputation across eastern and central Africa. “It is regarded as one of the world’s most deadly snakes, mainly due to its size – it can reach three to four metres but averages two to three metres – and its aggressive demeanour,” explained Rob Gandola of the Herpetologcal Society of Ireland.
It is also one of the quickest land snakes, rising up off the ground a metre or more and actively pursuing its prey at up to 20km/h. It is territorial and tends to strike repeatedly at potential prey or aggressors.
“Mambas are pretty good generalists in their diet. They’ll eat anything they can kill from rodents to birds and even other snakes,” he said.
They can live in a variety of habitats, have a massive distribution range and a tendency to turn up in people’s homes.
Previous research had shown that snake toxin can open up pain pathways along nerve cells in humans and animals, but the French group found a substance in black mamba venom that does the opposite, blocking off pain.
Studies with mice showed the substance, mambalgin, could stop pain as effectively as morphine but did not trigger side-effects such as respiratory distress, the authors write. Mambalgin is a nerve blocker that complements the attack on the neural pathways in the mamba’s prey, Mr Gandola said. “Basically, these peptides help to overload the nervous system . So the end result is the paralysis you see with mamba envenomation. It’s definitely not there to inhibit pain transmission,” he said.
“It is essential to understand pain better to develop new analgesics,” the French authors write. “The black mamba peptides discovered here have the potential to address both of these aims.”
