Baclofen binding sites in rat kidney.
The occurrence and distribution of gamma-aminobutyric acidB (GABAB) receptor binding sites were examined in cryostat sections of the rat kidney using [3H](-)-baclofen as ligand. Specific binding was saturable and of high affinity, and was characterized by a Kd value of 24.6 nM and a Bmax of 0.17 pmol/mg tissue. Specifically bound [3H](-)-baclofen was displaced by various agonists and antagonists in a manner consistent with their known order of potency at GABAB receptors. Autoradiographic experiments showed baclofen binding to have a characteristic pattern of distribution within the cortex, whereas the medulla was not labeled. These findings are consistent with the presence of GABAB receptors in the kidney cortex, and suggest a role for GABA in the modulation of renal calcium and/or potassium transport.
Erdö
S L
SL
Zentrum Anatomie, Georg-August-Universität, Göttingen, F.R.G.
D000818:Animals; D001345:Autoradiography; D001418:Baclofen / Q000378:metabolism*; D007668:Kidney / Q000737:chemistry*; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000032:analysis*
D011963:Receptors, GABA-A; D001418:Baclofen