“Catnip”: Understand the effects of catnip on felines

Catnip, also known as “catnip”, in the English translation, causes pleasant sensations for cats, in addition to helping with practical matters.

When cats rub, roll, chew or lick leaves of the herb, they don’t just revel in the plant’s intoxicating substances. The behavior also leads to the release of compounds that can protect cats from mosquitoes, according to new research from Japan.

Compounds called iridoids in catnip leaves (Nepeta Qatar) and the vine plant (actinidia polygamma) act as an insect repellent, as they are released when cats rub their bodies against the leaves, the same team found in a study published last year.

Catnip and matatabi are plants with aromatic flowers and leaves that grow in many places around the world. Dried leaves are also used in cat toys.

The group’s latest research has shown that the way cats lick and chew leaves causes 10 times the amount of these compounds to be released, on damaged leaves, making the insect repellent properties more effective.

With the help of 16 cats, the researchers compared feline responses to intact matatabi leaves, and to leaves crushed and ripped by hand by the scientists. Cats showed a more prolonged interest in interacting with damaged leaves than with intact leaves.

And then, to test whether the cats were reacting specifically to iridoids, the cats were given bowls of nepetalactone and nepetalactol — important active ingredients in catnip and matatabi, respectively.

“Cats show the same response to iridoid cocktails as to natural plants, except for chewing,” said Masao Miyazaki, a professor in the department of biological chemistry and food science at the University of Iwate in Japan, in a press release. “They lick the chemicals off the plastic dish, rub it and roll it on the dish.”

It’s the plant’s scent that triggers the behavior, according to research.

“When iridoid cocktails were placed in bowls, which were covered by a perforated plastic lid, the cats still behaved with licking and chewing, even though they could not come into direct contact with the chemicals,” Miyazaki said. “This means that licking and chewing is an instinctive behavior triggered by olfactory stimulation of the iridoids.”

In the case of matatabi, damaging the leaves triggered the release of other iridoids.

“Nepetalactol accounts for more than 90% of the total iridoids in intact leaves, but this drops to about 45% in damaged leaves as other iridoids greatly increase,” he said. “The altered iridoid mixture corresponding to damaged leaves promoted a much more prolonged response in cats.”

The work could help identify plant enzymes that could be used as insect repellents for humans, the study said.

Miyazaki said catnip and matatabi pose no risk to cats and are not addictive. The plants likely gave the cats a feeling of “euphoria,” he explained via email.