Presynaptic gamma-aminobutyric acid type B receptor-mediated regulation of vesicular gamma-aminobutyric acid transporter expression in the gerbil hippocampus.
Changes in vesicular gamma-aminobutyric acid (GABA) transporter (VGAT) expression in the gerbil hippocampus after treatment with baclofen (GABA(B) receptor agonist) or phaclofen (GABA(B) receptor antagonist) were investigated to identify the GABA(B) receptor-mediated regulation of VGAT expression. In the baclofen-treated seizure-resistant gerbils, VGAT expression was significantly reduced, as compared with the control animals, thus the VGAT immunoreactive pattern in these gerbils was similar to that in control seizure-sensitive (SS) gerbils. In the phaclofen-treated SS gerbils, VGAT expression was dramatically elevated, compared to SS gerbil controls. Our findings demonstrated that GABA(B) receptor-mediated regulation of VGAT expression may be another mechanisms for presynaptic GABA release, which is accompanied by a reduction in Ca(2+) conductance by the inhibition of voltage-gated Ca(2+) channels.
Kang
Tae-Cheon
TC
Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea. tckang@hallym.ac.kr
Park
Seung-Kook
SK
Hwang
In Koo
IK
An
Sung-Jin
SJ
Won
Moo Ho
MH
D000818:Animals; D002352:Carrier Proteins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D050485:GABA Plasma Membrane Transport Proteins; D005786:Gene Expression Regulation / Q000502:physiology*; D005849:Gerbillinae; D006624:Hippocampus / Q000737:chemistry / Q000378:metabolism*; D008565:Membrane Proteins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D026901:Membrane Transport Proteins; D027361:Organic Anion Transporters; D018080:Receptors, GABA-B / Q000502:physiology*; D017661:Receptors, Presynaptic / Q000502:physiology*
D002352:Carrier Proteins; D050485:GABA Plasma Membrane Transport Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D027361:Organic Anion Transporters; D018080:Receptors, GABA-B; D017661:Receptors, Presynaptic