How arginine enhances the effect of GABA
GABA improves sleep and increases the release of growth hormone, but the effect of supplementation is often modest. This is mainly because it is difficult for GABA to pass to blood brain barrier, and to reach the brain. In 2002, researchers from the University of Madras in India published an animal study showing that L-arginine increases GABA uptake by the brain.
Study
The researchers experimented with rats. They gave their test animals injections with compounds such as L-arginine and GABA in their small intestine. To some degree, this form of administration imitates the effect of oral administration.
Results
Both L-arginine and GABA increased the GABA concentration in the brain of the rats. The combined addition of L-arginine and GABA, however, caused an even greater increase in GABA concentration.
L-Arginine is a precursor of nitric oxide [NO]. The arginine analog N-nitro-L-arginine methyl ester [L-NAME] blocks the conversion of L-arginine to NO. Administration of L-NAME ensured that L-arginine no longer increased GABA uptake by the brain.
Conclusion
"Our study shows that L-arginine increases blood-brain barrier permeability to GABA and that L-NAME completely abolishes this", write the researchers. "We believe that these effects are mediated by NO and that NO contributes to increased blood-brain barrier permeability to GABA."
If that's right, then supplements like beet juice or L-citrulline could also improve the effect of GABA. And probably those combinations work even better than the combination with L-arginine.
Source: Brain Res Bull. 2002 Jan 15;57(2):231-6.
GABA improves sleep and increases the release of growth hormone, but the effect of supplementation is often modest. This is mainly because it is difficult for GABA to pass to blood brain barrier, and to reach the brain. In 2002, researchers from the University of Madras in India published an animal study showing that L-arginine increases GABA uptake by the brain.
Study
The researchers experimented with rats. They gave their test animals injections with compounds such as L-arginine and GABA in their small intestine. To some degree, this form of administration imitates the effect of oral administration.
Results
Both L-arginine and GABA increased the GABA concentration in the brain of the rats. The combined addition of L-arginine and GABA, however, caused an even greater increase in GABA concentration.
L-Arginine is a precursor of nitric oxide [NO]. The arginine analog N-nitro-L-arginine methyl ester [L-NAME] blocks the conversion of L-arginine to NO. Administration of L-NAME ensured that L-arginine no longer increased GABA uptake by the brain.
Conclusion
"Our study shows that L-arginine increases blood-brain barrier permeability to GABA and that L-NAME completely abolishes this", write the researchers. "We believe that these effects are mediated by NO and that NO contributes to increased blood-brain barrier permeability to GABA."
If that's right, then supplements like beet juice or L-citrulline could also improve the effect of GABA. And probably those combinations work even better than the combination with L-arginine.
Source: Brain Res Bull. 2002 Jan 15;57(2):231-6.
