Neuroscience For Kids
NO (Nitric Oxide) for Snakebite
August 19, 2011
You have just been bitten by an Eastern Brown
snake. The snake's highly neurotoxic venom is making it's way through
your body. In time, the venom will prevent the release of acetylcholine from your neurons, your
breathing will stop and you could die. What do you do?
In a few years, you might be able to apply an ointment to the bite to slow the spread of venom and save your life. This ointment could be based on the research of Australian scientists who studied the effect of an ointment that contains nitric oxide (NO).
Nitric oxide works by slowing the pump that brings chemical molecules into the lymphatic system. Using this knowledge, the scientists developed an experiment and found that NO-containing ointment slowed the spread of an injected simulated venom into the lymphatic system of human subjects. Without the ointment, the venom took only 13 minutes to get from the foot to the groin; when the NO ointment was applied to the injection site, the venom took 54 minutes to travel from the foot to the groin.
The NO-containing ointment also delayed the symptoms of Eastern Brown snake venom in anesthetized rats. Without ointment, rats stopped breathing 65 minutes after the venom was injected; when the NO ointment was placed on the leg 20 seconds after the venom was injected, the time when rats stopped breathing went up to 96 minutes.
The use of NO-containing ointment still has some problems. For example, it may be that the ointment is useful only if it is applied very soon after a bite and it may not work for all venoms. Certainly, the ointment will not cure a snakebite, but it may buy enough time for people to get to the hospital for help.
References and more information:
- Saul, M.E., Thomas, P.A., Dosen, P.J., Isbister, G.K., O'Leary, M.A., Whyte, I.M., McFadden, S.A. and van Helden, D.F., A pharmacological approach to first aid treatment for snakebite, Nature Medicine, 17:809-811, 2011.
- 1998 Nobel Prize Announcement for nitric oxide research
Copyright © 1996-2011, Eric H. Chudler, University of Washington
