A study conducted by scientists at The Scripps Research Institute in San Diego, California shows that the hypocretin molecule in the brain may actually make some people more likely to become addicted to cocaine than others, according to a report published by Science Daily. The hope now is that medications can be developed to specifically target the body’s hypocretin system and that, when coupled with cognitive behavioral therapies, they can work to better treat cocaine addiction.
This discovery can perhaps better explain why some people take a drug and are instantly addicted to it, while others can take a drug for the first time and walk away, or take the drug several times before an addiction finally begins to take hold. Because the mechanisms of the brain are so complex at the molecular level, scientists are working to better understand how it happens that a person can go from being an occasional drug user to suffering from full-blown addiction, and hypocretin may have the answer.
Hypocretin’s is part of the larger picture that is the body’s hypothalamic hypocretin/orexin (HCRT) system, which is a network that sends signals to the brain. Scientists have known that the HCRT system is involved in how the brain reacts to illicit drugs and alcohol, but until now they were not quite sure where it factored into cocaine addiction.
Another name for hypocretin is orexin, and the main role of hypocretin in the body is to regulate arousal, appetite, and wakefulness. One of the more common forms that narcolepsy can take on, wherein the sufferer has a temporary loss of muscle tone (known as cataplexy), is actually caused by the depletion of orexin in the brain as a result of the cells that produce it actually turning on it and destroying it.
The study that the scientists at The Scripps Research Institute conducted involved two groups of rats. The first group of rats was given the option of taking cocaine for an hour per day, the way a short-term, occasional drug user would use the drug. The second group of rats were permitted to take cocaine for six hours per day, which more closely resembled the habits of someone who was addicted to the drug.
It was discovered that the second group of rats, in compulsively using cocaine, actually sensitized their HCRT systems to the point where their systems actually sought out more of the drug. This is because the more cocaine that was introduced to their systems, the more hypocretin their bodies made, which led to an overactive central amygdala. This overactive state created anxiety in the rats that caused them to seek out more of the drug, increasing their daily intake of it in much the same way as humans do.
Now here’s where potential treatment may come in. When the scientists gave the rats what they referred to as an “antagonist” to block activity at one of their two central amygdala’s HCRT receptors, they actually became less interested in seeking out more cocaine. This further supports the idea that focusing on the HCRT system can provide additional options for successful treatments against addiction and even against a potential relapse.