Molecular Link Between the Active Component of Marijuana and Alzheimer's Disease Pathology

[KittyWampus]

37. As someone who smoked pot on a prodigious level many years ago it most certainly is not.

Last edited Sat Mar 9, 2013, 02:10 PM - Edit history (1)

It's sad how far into denial some pot smokers are. The Science isn't behind you.

How marijuana makes you forget

The drug impairs users’ working memory — the ability to retain and use information over short periods of time. Neuroscientists Giovanni Marsicano of the University of Bordeaux, France, and Xia Zhang of the University of Ottawa Institute of Mental Health Research now show that this common side effect occurs because of a previously unknown signalling mechanism between neurons and non-neuronal cells called astrocytes. Their work is published today in Cell1.

The star-shaped astrocytes have long been considered nothing more than support cells that protect neurons. “Our study provides compelling evidence that astrocytes control neurons and memory,” says Zhang. “The supporting actor has become the leading actor.”

The psychoactive ingredient of marijuana is tetrahydrocannabinol (THC). Using microelectrodes implanted into the brains of anaesthetized rats, the researchers found that the compound weakens the connections, or synapses, between neurons in the hippocampus, a structure that is crucial for memory formation.

They repeated these experiments in two types of mice that had been genetically modified to alter their production of CB1 receptors, the molecules that interact with THC in the brain. One mouse strain lacked CB1 receptors in hippocampal neurons that synthesize the neurotransmitter glutamate; the other lacked them in those that synthesize the neurotransmitter GABA.

http://www.nature.com/news/how-marijuana-makes-you-forget-1.10152#/ref-link-1