Cannabis-Induced Appetite Stimulation Explored in Rodent Experiments

Researchers at Washington State University (WSU) recently published a study examining the connection between cannabis and appetite (1). They examined the effect of cannabis ingestion on rodents to gauge their brain activity and behavior relating to food (1). As explained in the introduction of the study, cannabis increases appetite, but the neurobiological processes that regulate this are not yet fully known (1). The researchers conducted the study with the hypothesis that appetite stimulation is increased by the cannabinoid-1 receptors (CB1R) in the mediobasal hypothalamus (MBH), which stimulate Agouti Related Peptide (AgRP) neurons necessary for promoting food-seeking behavior (1). The study, “Cannabis Sativa targets mediobasal hypothalamic neurons to stimulate appetite,” was published in December 2023 in the journal Scientific Reports (1).

In several different experiments, mice and rats were exposed to vaporized cannabis that contained 7.8% tetrahydrocannabinol (THC) and 0.5% cannabidiol (CBD), and then their feeding habits and other activities were recorded (1). Researchers also used in vivo calcium imaging of MBH neurons (1).

Some of the outcomes listed in the results section included the following (1):

• Cannabis augments food-motivated behavior
• Cannabis augments metabolic activity
• Vapor cannabis stimulates food anticipatory responses in MBH neurons
• CB1R activation disinhibits AgRP neurons
• AgRP neurons regulate the appetite stimulatory properties of cannabis sativa

“Based on these results, we conclude that MBH neurons contribute to the appetite stimulatory properties of inhaled cannabis,” the researchers concluded (1).

“When the mice are given cannabis, neurons come on that typically are not active,” explained Jon Davis, lead study author and assistant professor of neuroscience at WSU (2). “There is something important happening in the hypothalamus after vapor cannabis.”

The data, the researchers explained in the discussion section, are the first to provide a detailed explanation on the in vivo connection between cannabis ingestion and appetite stimulation (1).

“We now know one of the ways that the brain responds to recreational-type cannabis to promote appetite,” Davis added (2).

References

1. Wheeler, E. C.; Choi, P.; De Howitt, J.; Gill, S.; Watson, S.; Yu, S.; Wahl, P.; Diaz, C.; Mohr, C.; Zinski, A.; et al. Cannabis sativa targets mediobasal hypothalamic neurons to stimulate appetite. Scientific Reports 2023, 13 (1) DOI: 10.1038/s41598-023-50112-5.
2. Cannabis activates specific hunger neurons in brain. EurekAlert!. January 16, 2024.