What is it about the bite of the famous Texas coral snake that makes it so excruciatingly painful for so long? New research has pinpointed the cause, and it literally makes your nerves feel like they're being dipped in acid.
The bite of Micrurus tener tener contains a toxin called MitTx which is made of two compounds that on their own don't cause any pain. But when the two combine, they activate ASIC1, an acid sensing ion channel on your nerve fibres. It attacks the part of your nerves that are designed to react with pain when exposed to low pH, which accounts for the excruciating pain of the bite. These nerves generally signal when something has gone severely wrong with your body to drop the pH, like a massive injury, but the venom triggers them without actually acidifying your tissue.
What makes this discovery particularly interesting from a pain perspective is that the majority of research into acid pathways have focused on ASIC3, which is mostly used for sensory neurons. ASIC1, on the other hand, is distributed throughout the brain and used for a number of purposes — it takes far less of the toxin to activate. Hopefully this research will lead into a more effective way of counteracting the bite of this snake, and alleviating the pain it can cause.
Image credit: National Natural Toxins Research Center at Texas A&M University-Kingsville