Pharmacological characterization of prostaglandin E 2 EP2 and EP4 receptors in male rat locus coeruleus neurons ex vivo.

Autor: Nazabal A; Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/ EHU), E-48940 Leioa, Bizkaia, Spain., Mendiguren A; Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/ EHU), E-48940 Leioa, Bizkaia, Spain. Electronic address: aitziber.mendiguren@ehu.eus., Pineda J; Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/ EHU), E-48940 Leioa, Bizkaia, Spain.
Jazyk: angličtina
Zdroj: Biochemical pharmacology [Biochem Pharmacol] 2024 Dec; Vol. 230 (Pt 3), pp. 116602. Date of Electronic Publication: 2024 Nov 05.
DOI: 10.1016/j.bcp.2024.116602
Abstrakt: The inflammatory mediator prostaglandin E 2 (PGE 2 ) binds to G s -coupled EP2 and EP4 receptors. These receptors are located in the locus coeruleus (LC), the principal noradrenergic nucleus in the brain, but their functional role remains unknown. In this study, the PGE 2 EP2 and EP4 receptors in LC cells from male rat brain slices were pharmacologically characterized by single-unit extracellular electrophysiology. The EP2 receptor agonists butaprost (0.01-10 μM) and treprostinil (0.03-10 µM) and the EP4 receptor agonists rivenprost (0.01 nM-1 µM) and TCS2510 (0.20 nM-2 µM) increased the firing rate of LC neurons in a concentration-dependent manner. The EP2 receptor antagonist PF-04418948 (10 nM) hindered the excitatory effect of butaprost and treprostinil while the EP4 receptor antagonist L-161,982 (30 and 300 nM) blocked the excitatory effect caused by rivenprost and TCS2510. The effects of butaprost and rivenprost were prevented by extracellular sodium replacement but were not modified by the protein kinase A (PKA) activator 8-Br-cAMP (1 mM) or the inhibitor H-89 (10 μM). However, the G βγ subunit blocker gallein (20 μM) hindered the stimulatory effect of butaprost while the G αs subunit inhibitor NF449 (10 µM) prevented that of rivenprost. Finally, rivenprost-induced stimulation (30 nM) was not occluded by butaprost (1 µM). In conclusion, activation of EP2 and EP4 receptors excites LC noradrenergic neurons through sodium-dependent currents via different G protein subunits in male rat brain slices. EP2 and EP4 in the LC may constitute pharmacological targets for the treatment of pain, fever, drug addiction, anxiety and neuroinflammatory diseases.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier Inc.)
Databáze: MEDLINE
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