D-Aspartate binding sites in rat Harderian gland.
Amino Acids
; 38(1): 229-35, 2010 Jan.
Article
in En
| MEDLINE
| ID: mdl-19153642
ABSTRACT
Radioligand binding of D-[(3)H]aspartic and L-[(3)H]glutamic acids to plasma membranes from rat Harderian gland was evaluated. Binding was optimal under physiological conditions of pH and temperature, and equilibrium was reached within 50 min. Specific binding for D-Asp and L-Glu was saturable, and Eadie-Hofstee analysis revealed interaction with a single population of binding sites (for D-Asp K(d) = 860 +/- 28 nM, B(max) = 27.2 +/- 0.5 pmol/mg protein; for L-Glu, K(d) = 580 +/- 15 nM and B(max) = 51.3 +/- 0.8 pmol/mg protein). L-[(3)H]glutamate had higher affinity and a greater percentage of specific binding than did D-[(3)H]aspartate. The pharmacological binding specificity of L-[(3)H]glutamate indicated an interaction with NMDA-type receptors. Specifically, the order of potency of the displacing compound tested was L-Glu > D-Asp > NMDA > MK801 > D-AP5 > glycine. For D-[(3)H]aspartate, the data revealed an interaction of D -Asp with either NMDA-type receptors or putative specific binding sites.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Aspartic Acid
/
Harderian Gland
Limits:
Animals
Language:
En
Journal:
Amino Acids
Journal subject:
BIOQUIMICA
Year:
2010
Document type:
Article
Affiliation country:
Italy