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marijuana loss of appetite

Marijuana loss of appetite

Understanding how pot sparks hunger has wider implications for the study of appetite control.

But much remains unknown about how the body processes cannabinoids, Kunos says. For example, activating CB1 with a drug, as Horvath’s team did, may cause a different reaction from when it is stimulated with cannabinoids the body naturally produces.
Sudden attacks of ‘the munchies’ are triggered by a change in the hormone released by neurons.

The finding is intriguing, says Uberto Pagotto, a neuroscientist at the University of Bologna who has studied cannabinoids for many years. “It gives us a different starting point to look at CB1 receptors and the mitochondria,” he says.
Smoking marijuana may stoke a yearning for crisps, but understanding how it affects hunger is relevant not just to those who indulge in it. The drug has yielded a ripe target for scientists who seek to stimulate or suppress appetite: the receptor CB1, found in cells throughout the body.
Kola, B. et al. J. Biol. Chem. 280 , 25196 – 25201 ( 2005 ).
“Until recently, many people I’ve been speaking to have lamented that it has been incredibly hard to get funding to do this research,” says George Kunos, an expert on cannabinoids and appetite at the US National Institutes of Health in Bethesda, Maryland. But some companies have renewed their interest. One possible approach is to target only the receptors present in the peripheral nervous system, so as to avoid the psychiatric side effects of inhibiting CB1 in the brain.
Now neuroscientist Tamas Horvath, of Yale University in New Haven, and colleagues report in Nature that nerve cells called pro-opiomelanocortin (POMC) neurons play a key role in this process 3 . POMC had generally been thought to promote satiation, but Horvath’s team found that POMC neurons in the brain release not just a hunger-suppressing hormone, but also one that promotes appetite.

In 2008, for example, Sanofi-Aventis was forced to withdraw rimonabant after studies showed that the weight-loss drug was linked to depression. As a result, pharmaceutical firms including Merck, Pfizer and AstraZeneca stopped their research on similar compounds. Some of these potential treatments were in late stages of development, and pulling them likely cost the industry several billion dollars, reckons Steven Heymsfield, an obesity researcher now at Pennington Biomedical Research Centre in Baton Rouge, who had worked on Merck’s CB1 drug, taranabant.

Sudden attacks of ‘the munchies’ are triggered by a change in the hormone released by neurons.