Sleep and the GABA Receptor

I found a remarkable study out of the University of McGill in Montreal, Canada.

 "Dynamic changes in GABA A receptors on basal forebrain cholinergic neurons following sleep deprivation and recovery"

          "These changes in membrane GABA receptors would be associated with increased GABA-mediated inhibition of cholinergic cells following prolonged waking and diminished inhibition following sleep and could thus reflect a homeostatic process regulating cholinergic cell activity and thereby indirectly cortical activity across the sleep-waking cycle."

OK, Ok translation...... They measured the number of GABA receptors on the cell membrane and found that the number of receptors on the membrane changes when the subject is either sleep deprived or rested. They actually stained the GABA receptors sitting on the membrane. Here is a picture of the GABA receptor (the yellow thing) sitting  ON the membrane:



The little yellow things are the GABA A receptors. But the most interesting part is that they circulate in and out of the membrane. They are picked up by a little 'submarine' and brought inside the cell.  Here is a picture of the GABA receptors and the submarines:



Now why do we care? Well let's get back to the study above. They found that if the animal was sleep deprived there were many GABA receptors sitting on the membrane. But if the animal was rested, the GABA receptors were inside the cell (postsynaptic neuron) in the submarine. Here is a picture of that:

Again, why do we care? Because the submarine in Down syndrome does not work well. Down syndrome end up with GABA receptors on the membrane longer than normal. Are we in a constant state of sleep deprivation?
Tomorrow we will review the consequences of having the GABA receptor on the membrane too long.