Happy M Day

Chemistry That Matters

Posted Oct 23, 2017

Source: Shutterstock

Happy Mole Day!  It is a reason to be happy. Moles are a chemical unit. There are 6.02 x 1023 atoms in one mole. Scientists need to know that because at that tiny bit of mass, you can’t go by pounds or inches or the ordinary sorts of measurement.

When my kids were in elementary school Pi Day was a bigger deal than mole day. I get it. It’s not that math is more fun than chemistry, but because Pi (3.14 etc.)  is punnier. You can have pizza Pi’s and ice cream Pi’s and all that sort of stuff. Moles conjure up bad skin.

But they are also the cute creatures who in their own way have taught us a lot about chemistry. My chemical interest these days is hormones, not just because menopause has come and gone, but because I’ve just finished a book on the history of hormones.

When I heard mole day, I thought about the rodent kind and what they’ve taught us about the chemical called oxytocin. For years, we’ve known that oxytocin was the hormone that fostered contractions in pregnant women and also helped nursing moms make milk. (That’s also why when nursing mom’s start breastfeeding newborns, their womb contracts at the same time. ) But there’s more. Researchers learned shortly after that, that oxytocin also fosters mother-baby bonding. And much of the pioneering oxytocin-bonding research was done in moles by Sue Carter, director of the Kinsey Institute.

I did a little mole searching, in honor of the other-kind-of-mole day and found this study, also on oxytocin and also moles: It found that injecting oxytocin into mole brains made them huddle more with their colony-mates. Injecting an oxytocin-blocker into their brains made them more aloof.

What does this mean for humans? We’re not sure. Oxytocin probably does play a role in mother-baby bonding, and perhaps human-human bonding. And you can buy all kinds of oxytocin sprays and candies touted to promote social interactions… and more. But we’re not there yet. The studies are intriguing but spraying or sniffing oxytocin may not have the same impact as getting it injected into the brain.

So on this very special holiday, MOLE DAY 2017, it’s a good time to think about how the unit of moles has helped foster chemical research, but the other kinds of moles, the little hairy rodents, have done a lot of good for understanding the science of brain chemistry too


Horm Behav. 2014 Apr;65(4):380-5. doi: 10.1016/j.yhbeh.2014.02.003. Epub 2014 Feb 13.