If you want to see a cat behave like it’s on drugs, give them a bit of nepeta cataria, better known as catnip. Dried or fresh, the catnip leaf has a clear effect on most cats, making them behave like they are “high.”
But why? What is it about the catnip plant that creates this reaction? And what, if any, purpose does the plant serve for our feline friends beyond euphoria?
The chemical compound that gives them the high
As explained in a TedEd video by Jaap de Roode, these were questions Japanese cat behavior expert Masao Miyazaki and chemist Toshio Nishikawa set out to study in 2013. Their research teams started studying a plant called silver vine, which sparks a similar response in cats.
First, they extracted individual chemical compounds from the plant and dribbled them in various combinations onto filter papers. When they brought in cats to see which compounds the felines were drawn to, it became clear. The cats overwhelmingly chose the filter papers containing the compound nepatalactol.
Then the researchers tested the blood of cats that had interacted with nepatalactol and found their systems flooded with endorphins, stress-relieving hormones that block pain signals and increase happy feelings. Catnip contains a similar chemical, nepatalactone, that gives cats that signature “high.”
Big cats respond to the eurphoric compound in catnip as well
And it’s not just house cats that have this response. The researchers took their treated filter papers to zoos to test them on big cats like leopards, lynxes, and jaguars. They, too, “dove face first” into the papers that contained the nepetalactol compound. This discovery led scientists to believe there must be some evolutionary reason for this shared trait.
The silver vine researchers presented their findings at a conference and got some interesting feedback. An evolutionary biologist pointed out that nepetalactol and nepetalactone are classified as an iridoid, which has properties that repel insects. Could it be possible that cats were using these plants as a natural bug spray?
What mosquitos have to do with catnip
The best guess of researchers is that cats are attracted to catnip and silver vine specifically for this bug repellent effect. The euphoric state causes cats to rub against the plant (which we can see with our house cats when they roll around in it on the floor). The rubbing distributes the nepetalactone onto their fur.
“To test this,” the video explains, “researchers set up cages of mosquitoes that cats could stick their heads into. And sure enough, the cats that had been treated with nepetalactol got fewer mosquito bites than the cats in the control group. The same effect was true for the scientists who’d volunteered their arms in solidarity with their feline subjects.”
The researchers also found that biting, licking, and rubbing the plant also made it release more of the mosquito-repelling compound.
“So your cat isn’t just ripping open their bags of catnip to be annoying,” the video concludes. “Their evolutionary instincts are just trying to get even more of that bug protection.”
Isn’t nature amazing?
