Glutamate opens the synaptic gates. GABA holds the gates closed.
"The astrocytes, which are the Cinderellas of the brain, consume large amounts of oxygen mopping up and recycling the GABA and the glutamate, which is a neurotoxin," Somersalo said.
More oxygen requires more blood flow, although the connection between cerebral metabolism and hemodynamics is not fully understood yet.
All together, "It's a surprising expense to keep inhibition on," he said.
The group plans to more closely compare energy use of excitatory and inhibitory neurons by running simultaneous simulations of both processes.
The researchers are plumbing basic science but their goal is to help solve human problems.
Brain disease or damaging conditions are often difficult to diagnose until advanced stages. Most brain maladies, however, are linked to energy metabolism and understanding what is the norm may enable doctors to detect problems earlier.
The toll inhibition takes may, in particular, be relevant to neurodegenerative diseases. "And that is truly exciting" Calvetti said.
|Contact: Kevin Mayhood|
Case Western Reserve University