The aim of this study was to investigate adenosine receptor sites in whole brain membranes of the saltwater teleost fish, Mugil cephalus, using the Al receptor selective agonist, [H-3]- N-6-cyclohexyladenosine ([H-3]-CHA). Specific binding was saturable and reversible. A single class of high-affinity binding sites was identify, showing K-d and B-max values of 1.43 +/- 0.26 nM and 69.5 +/- 5.4 fmol/mg protein, respectively. In competition experiments, the following adenosine analogues, CHA, (2-[p-(2-carboxyethyl)-phenylethylamino]-5'-N-ethylcarboxamidoadenosine) (CGS21680), 5'-(N-cyclopropyl)carboxamidoadenosina (CPCA) and N-6-[2-(3,5-dimethoxyphenyl)-2-(2methylphenyl)-ethyl]adenosine (DPMA), displaced [H-3]-CHA specifically bound to brain membranes, revealing that the high-affinity binding sites have some pharmacological properties of mammalian Al adenosine receptors. Furthermore, our findings indicate that in captivity chemical pollution determines a decrease of the K-d value corresponding to a 5-fold increase in affinity, whereas it does not induce any variation of the receptor density. (C) 1998 Elsevier Science Ltd. All rights reserved.
|Autori:||Giannaccini G; Betti L; Dini M; Giannoni P; Ori M; Mazzoni MR; Lucacchini A|
|Titolo:||Influence of chemical pollution on brain adenosine receptors of Mugil cephalus|
|Anno del prodotto:||1998|
|Digital Object Identifier (DOI):||10.1016/S0269-7491(98)00131-6|
|Appare nelle tipologie:||1.1 Articolo in rivista|