Hi,
From what I read, GABA doesnot cross Blood Brain barrier. It enters brain if BBB is damaged and if there are any leaks. However, a few papers say that a small fraction does get transported across the BBB, via a carrier. GABA is also used as a crude test to see if BBB is intact. If you feel the effects of GABA: BBB is leaky! Ron has done quite bit of research on BBB and he may know more about GABA transport. I wonder if we survey pWPs here on the use of GABA, may be we get the answer to a million $$ question(Ron's hypothesis) "Is BBB intact in PWPs?" I will wait till Ron gets back from his vacation......

girija