Although cannabis has long been known to cause memory loss, research published in the journal Cell has managed to explain the mechanism of this process. Juan Mendizabal and Pedro Grandes, neuroscientists of the UPV/EHU, have participated in the research together with France, Canada, China and the United States.
Tetrahydrocannabinola (THC) is the main psychoactive component of marijuana. Like any other medicine, THC acts on certain protein receptors. In this case, THC acts on CB1 receptors, i.e. on astrocytes. These receptors when activated in the hippocampus release glutamate, which has an exciting function in the central nervous system. The chain continues. Glutamate released from astrocytes causes the activation of NMDA receptors in neurons, so other glutamate receptors, called AMPA, disappear from the neuronal surface. When AMPA disappears, communication between the hippocampus neurons is depressed and therefore memory is altered.
UPV neuroscientists have located the CB1 receptor in astrocytes. The first evidence is the role of astrocytes, some nervous system cells, in a cognitive function such as memory. In fact, until now they were mainly associated with the function of support, nutrition and protection of neurons, that is, they were said to have a secondary function.
The experiment was done on the mouse. Wild mice with CB1 protein and genetically modified mice that do not contain this protein have been used. They have found that in the latter, THC does not affect neuronal synapses, the hippocampus.
These results show that CB1 receptors present in astrocytes play a fundamental role in cognitive impairment caused by cannabinoids. The question is whether marijuana launches a similar mechanism in the human brain. You could expect it to, because this drug alters short-term memory, both in humans and rodents.
Source: www.basqueresearch.com