The findings could bring scientists closer to learning what causes schizophrenia, a disease that has bewildered researchers for decades and that torments an estimated one percent of the population worldwide. The team studied 10 schizophrenic patients ages 18 to 49 for levels of anandamide by measuring their cerebrospinal fluid, a liquid that surrounds the brain and spinal cord. The levels of anandamide did not vary according to age, type of medication the patients were taking, or whether the patients were male or female. We hope that by understanding how anandamide works in the brain, we can arrive at a better understanding of schizophrenia and develop more effective treatments. Although the cause of schizophrenia is not known, the disease has long been associated with abnormally high levels of another brain neurotransmitter called dopamine.
Dopamine is largely responsible for stimulating movement and other motor behavior in the brain.
Current therapies for these diseases include drugs that either hinder dopamine production or block its ability to stimulate nerve cells. In findings published earlier this year, Piomelli's team reported that the effects of dopamine appear to be regulated by a network of marijuana-like anandamide. When these cannabinoid receptors were prevented from binding to anandamide in rats, the blocked nerve cells could not inhibit dopamine's effects, and the rats experienced severe uncontrolled motor activity. Piomelli said the latest findings suggest that anandamide could be playing one of two roles in schizophrenics' brains. One theory is that since dopamine levels are already high in those with the disease, anandamide levels rise in an effort to regulate the rising dopamine levels.