title: Activation of orexin/hypocretin type 1 receptors stimulates cAMP synthesis in primary cultures of rat astrocytes.
abstract: The effects of orexins, which are also named hypocretins, on cAMP formation were examined in primary cultures of rat astrocytes. Orexin A, an agonist of OX₁ and OX₂ receptors, stimulated cAMP production with an EC₅₀ value of 0.68 μM and potentiated the forskolin-induced increase in the nucleotide synthesis. [Ala¹¹-D-Leu¹⁵]orexin B, an agonist of OX₂ receptors, was inactive. The effects of orexin A were antagonized by SB 408124, a selective blocker of OX₁ receptors, but were not affected by TCS OX2 29, a selective antagonist of OX₃ receptors. We hypothesized that the activation of OX₁ receptors stimulated cAMP synthesis in primary rat astrocyte cultures.
authors.affiliation: Department of Pharmacodynamics, Medical University of Łódź, Muszyńskiego 1, PL 90-151 Łódź, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Woldan-Tambor
authors.forename: Kaja
authors.initials: K
authors.lastname: Biegańska
authors.forename: Anna
authors.initials: A
authors.lastname: Wiktorowska-Owczarek
authors.forename: Jolanta B
authors.initials: JB
authors.lastname: Zawilska
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism; D000242:Cyclic AMP / Q000096:biosynthesis*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D064446:Orexin Receptors; D000068797:Orexins; D010671:Phenylurea Compounds / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D018013:Receptors, Neuropeptide / Q000378:metabolism*
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D064446:Orexin Receptors; D000068797:Orexins; D010671:Phenylurea Compounds; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; C542397:SB 408124; D000242:Cyclic AMP