Above is one of the fabulous tapestries hung in Christiansborg Palace, Copenhagen. Commissioned by the current Queen, this one depicts the Vikings (great travellers themselves).
Having recently undertaken long distance travel across many time zones, the prevention of jet lag has been on my mind. Some of my friends swear by melatonin, especially the controlled release form. I am a fan of the natural melatonin stimulant – sunlight. Exposure to intense natural light is supposed to increase nocturnal melatonin levels and it is a good excuse to get out an explore wherever you have just landed!
That’s all well and good, but what is the relevance to the title of this post? One of the fellow authors of this blog, slowlywaving, recently regaled me with the fascinating story regarding evidence that anaesthesia interrupts circadian rhythms. It all revolves around the study of bees.
Bees have a stong circadian timer which governs much of their behaviour and also helps with their navigation in conjunction with the sun compass. Amongst other things it enables them to judge how much time has passed whilst they have been in the hive so that when they leave the hive, they can maintain their heading back to a great source of nectar, even though the position of the sun may have changed dramatically.
A group of researchers decided to use bees to test the effect of anaesthesia on circadian rhythms. In our initial discussion, the thought was that the bees were anaesthetised with propofol and there was some discussion about how this could possibly be achieved (anyone trying cannulating a bee? do they even have veins? you can find the answer here if you are interested). As it turns out, isoflurane was used and the bees received a 6 hr daytime anaesthetic.
On awakening from the anaesthetic, the bees behaved in a manner consistent with them sensing a time 4-5 hours earlier than the actual time. They headed off to find their food at the bearing it would have been at, relative to the sun, several hours previously! They did a whole lot of fancy genetic testing and determined that the effect was related to dramatic slowing of the circadian rhythm. How cool! Interestingly night time perception was unchanged, which apparently fits with the hypothesis.
So how could we use this to prevent jet lag? Just imagine being anaesthetised (it would be much easier with propofol than isoflurane, assuming that it has the same effect) prior to being put on your long haul flight. You are then awoken at the same hour that you were anaesthetised, but in your new location and, voila, no jet lag!! Do you think it would take off? (sorry…)
The other fascinating part of the story revolves around tracking the bees. It involves tiny radar transponders and a disused airbase, but perhaps that can be a story for another day….
For those of you interested I have posted a copy of the article at aGasgal’s site