Register for an account


Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.


Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.


This Is Your Brain's Anti-Drug

Neuroskeptic iconNeuroskepticBy NeuroskepticMay 29, 2010 12:10 AM


Sign up for our email newsletter for the latest science news


What's youranti-drug? Well, it might well be hemopressin. At least, that's probably your anti-marijuana.

Hemopressin is a small protein that was discovered in the brains of rodents in 2003: its name comes from the fact that it's a breakdown product of hemoglobin and that it can lower blood pressure.

No-one seems to have looked to see whether hemopressin is found in humans, yet, but it seems very likely. Almost everything that's in your brain is in a mouse's brain, and vice versa.

Pharmacologically, hemopressin's literally an anti-marijuana molecule: it's an inverse agonist at CB1 receptors, which are the ones targeted by the psychoactive compounds in marijuana, and also by the neurotransmitters known as endocannabinoids. Cannabinoids turn CB1 receptors on, hemopressin turns them off.

Artificial CB1 blockers were developed as weight loss drugs, and one of them, rimonabant, made it onto the market - but it was banned after it turned out that it caused depression and anxiety in many people.

So hemopressin is Nature's rimonabant: in which case, it ought to do what rimonabant does, which is to reduce appetite. And indeed a Journal of Neurosciencepaper just out from Godd et al shows that it does just that, in rats and mice: injections of hemopressin reduced feeding.

Interestingly, this worked even when it was injected by the standard route under the skin - many proteins can't enter the brain if they're given this way, because they can't cross the blood-brain barrier, meaning that they have to be injected directly into the brain, which makes researching them much harder. So hemopressin, with any luck, will be pretty easy to study. Any volunteers for the first human trial...?


Dodd, G., Mancini, G., Lutz, B., & Luckman, S. (2010). The Peptide Hemopressin Acts through CB1 Cannabinoid Receptors to Reduce Food Intake in Rats and Mice Journal of Neuroscience, 30 (21), 7369-7376 DOI: 10.1523/JNEUROSCI.5455-09.2010

    3 Free Articles Left

    Want it all? Get unlimited access when you subscribe.


    Already a subscriber? Register or Log In

    Want unlimited access?

    Subscribe today and save 70%


    Already a subscriber? Register or Log In