By: Melissa Cornwell
According to the NIH, our enteric nervous system (ENS) has two main types of cannabis receptors (CBs). These receptors include CB1 and CB2 (along with G protein and other minor receptors). Our endocannabinoid system (ECS) plays an important role within this system. It has a major hand in motility and parastalsis (squeezing movements to propel food), inflammation and immunity, stomach/ intestinal secretions, pain pathways, nausea/ vomiting pathways, and appetite control. Hundreds of cannabis ingredients, such as cannabinoids, affect this system by binding to these receptors. When binding occurs, the cannabinoids can either activate it (start) or inhibit (stop) the receptor from doing its job. Each cannabis ingredient works by interacting and binding to these individual receptor sites, mimicking our own natural endocannabinoids, such as anandamide and 2-AG. What exactly is happening when cannabis interacts with our intestinal system? Research is far from complete, but lets explore some of what is known.
The CB1 receptor is the major receptor found in our enteric nervous system. Our enteric system consists of all body parts associated with digesting food, such as your stomach, esophagus, and “guts.” Manipulating this receptor appears to stimulate appetite, control nausea, increase pain threshold, affect stomach/ intestine contractions, help control stomach secretions, decrease inflammation, and stop mucosal lining damage in reflux disease (GERD). Activating this receptor can decrease stomach pressures, delay stomach emptying, and increase your appetite for high energy foods. Inhibiting this receptor was found to decrease appetite in rat studies. THC, the most abundant cannabinoid in cannabis, has been shown to majorly bind to this receptor (and to other receptors to a lesser extent).
The CB2 receptor is mainly found in immune/ inflammatory cells but is found in lesser amounts throughout the system. Manipulating this receptor leads to decreased inflammation, helps protect from bone loss, calms gut motility, and affects the emetic pathway (nausea/ vomiting). This receptor plays a key role in inflammatory bowel diseases. CBD, the second most abundant cannabinoid on the plant, has been shown to weakly bind to these receptors, but majorly acts by binding to other target sites. CBN, another cannabis cannabinoid, primarily binds to this receptor.
Examples of diseases affecting the enteric system include irritable bowel disease (IBD) and irritable bowel syndrome (IBS). IBD symptoms are partially due to gut spasms, pain, and inflammation. This disorder is thought to be caused from a genetic problem with immunity. Research shows that anandamide levels (a natural cannabinoid inside the human body) are much lower in these patients’ inflamed gut tissues. The inflammation leads the body to increase the number of cannabinoid receptors in the inflamed area. This helps control the inflammation by processing more cannabinoids. IBS is a disorder causing pain and motility issues. The exact disease cause is unknown but suffers have been shown to have easily stimulated gut spasms. Cannabis helps decrease the painful, debilitating cramps that comes with many of these enteric disorders by relaxing the smooth muscles that control the contractions. Essentially, it acts as a muscle relaxer for your digestive system.
Current treatment regimens for diseases of the enteric system leave much to be desired. The list of potential side effects from pharmaceutical therapies are disheartening and potentially debilitating. Cannabis has been labeled a “low risk” therapy regimen by many experts. This means that compared to alternatives, the potential side effects are less medically concerning. Studies report cannabis use may possibly lead to worsening of schizophrenic symptoms, temporary impairment and euphoria, tachycardia, low blood pressure, impeding thinking and psychomotor performance, tolerance development, respiratory infections/ lung injury in heavy cannabis smokers, decreased male fertility, and myocardial (heart) ischemia. Cannabis therapy is not for everyone and does come with some risks for some people. Patients are encouraged to consult their doctor prior to starting cannabis to prevent potential drug interactions and medical contraindications. Overall, cannabis should be considered a first line of therapy for certain diseases… certainly not a last resort option, especially in resistant cases.