Possible Interaction: Arginine and Gamma-Aminobutyric Acid

“AI is also expressed in various extrahepatic tissues and may play a role in regulating arginine levels and in providing ornithine for biosynthetic reactions that generate various critical intermediary metabolites such as glutamate, glutamine, GABA , agmatine, polyamines, creatine, proline, and nitric oxide.”

“In both cultured cerebral neurons and RINm5F cells, the addition of arginine induced the release of GABA , whereas neither high K(+) concentration nor glucose had any effect.”

“In these cells as well as in cultured cortical neurons, arginine stimulates the release of GABA and glutamate probably as the result of its electrogenic transport.”

“Pre-… with ARG and/or CAR significantly mitigated the neural changes induced by hypoxia and attenuated the elevated levels of NF-κB, …-α, IL-6, caspase-3, and BAX, while ameliorated the reduced levels of Bcl-2, NADR, DOP, SER, and GABA , with the best improvement … with the combination.”

“We conclude that basal NO production and moderate NO production (possibly induced by L-arginine ; 100 microM) inhibit basal GABA release from amacrine cells and GCL cells.”

“The contents of GABA and Glu in synaptosome were decreased in the presence of L-arginine.”

“The same dose of L-arginine , 60 min after administration, decreased the concentrations of both NO and GABA and increased the convulsion frequency of picrotoxin.”

“Moreover, GABA + L-Arg treated brains showed a fourfold increase in GABA level (383.3%, p < 0.01) when compared to controls.”

“Following microdialysis of L-arginine , muscle contraction augmented GABA levels (from 0.45+/-0.07 to 2.18+/-0.09 ng/10 microl) and attenuated changes in MAP and HR.”

“Following microdialysis of L-arginine , muscle contraction significantly attenuated GABA levels (from 1.34+/-0.19 to 0.33+/-0.10 ng/10 microl) and augmented changes in MAP and HR in response to muscle contraction.”

“Isoguvacine evoked an outward current (at -60 mV) in a concentration-dependent manner with an EC50 of 62+/-8 microM. The gamma-aminobutyric acid (…. L-Arginine (3 mM) also shifted the isoguvacine concentration-response curve to the left, with a new EC50 of 29+/-5 microM. L-Arginine (… GABA (….”

“Whole-cell patch-clamp recordings showed that the specific substrate of NOS L-arginine (L-Arg, 10(-4) M) or the NO donor sodium nitroprusside (10(-5) M) provoked a long-lasting inhibition of the current evoked by GABA (5 x 10(-6) M).”