LSL 60101, a selective ligand for imidazoline I2 receptors, on glial fibrillary acidic protein concentration.
The concentration of the astrocytic marker, glial fibrillary acidic protein (GFAP) was quantitated by immunoblotting (Western blotting) in the rat brain after treatment with the novel ligand for imidazoline I2 receptors LSL 60101 [2-(2-benzofuranyl)imidazole] and its 6-methoxy derivative LSL 60125. Chronic (7-21 days), but not acute (1 day) or short-term (3 days), treatment with LSL 60101 (10 mg/kg i.p.) markedly increased (44-49%) GFAP immunoreactivity in the rat cerebral cortex. In contrast, chronic (7 days) treatment with LSL 60125 (10 mg/kg i.p.) did not significantly modify GFAP concentrations. In vitro, both drugs displayed moderate high affinity and high selectivity for imidazoline I2 receptors versus alpha 2-adrenoceptors; however, only chronic treatment with LSL 60101 (10 mg/kg i.p.) but not with LSL 60125 (10 mg/kg i.p.) was associated with an up-regulation of imidazoline I2 receptors. These data indicate that glial imidazoline I2 receptors may have a direct physiological function related to GFAP expression and that LSL 60101 could be a good tool for the study of the implication of these receptors on astrocyte activation and neuronal regeneration.
Alemany
R
R
Department of Fundamental Biology and Health Sciences, University of the Balearic Islands, Palma de Mallorca, Spain.
Olmos
G
G
Escribá
P V
PV
Menargues
A
A
Obach
R
R
García-Sevilla
J A
JA
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism; D001572:Benzofurans / Q000494:pharmacology*; D001923:Brain Chemistry / Q000187:drug effects*; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D004146:Dioxanes / Q000378:metabolism / Q000494:pharmacology; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D019329:Idazoxan / Q000031:analogs & derivatives; D007093:Imidazoles / Q000494:pharmacology*; D054755:Imidazoline Receptors; D015151:Immunoblotting; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D001572:Benzofurans; D004146:Dioxanes; D005904:Glial Fibrillary Acidic Protein; D007093:Imidazoles; D054755:Imidazoline Receptors; C095677:LSL 60101; D011955:Receptors, Drug; C058525:2-methoxyidazoxan; C014282:cirazoline; D019329:Idazoxan