Further studies on the pharmacological profile of the neuropeptide S receptor antagonist SHA 68.
Neuropeptide S (NPS) regulates various biological functions by selectively activating the NPS receptor (NPSR). Previous studies demonstrated that the non-peptide molecule SHA 68 acts as a selective NPSR antagonist. In the present study the pharmacological profile of SHA 68 has been further investigated in vitro and in vivo. In cells expressing the mouse NPSR SHA 68 was inactive per se up to 10microM while it antagonized NPS-stimulated calcium mobilization in a competitive manner showing a pA(2) value of 8.06. In the 10-50mg/kg range of doses, SHA 68 counteracted the stimulant effects elicited by NPS, but not those of caffeine, in mouse locomotor activity experiments. In the mouse righting reflex assay SHA 68 fully prevented the arousal-promoting action of the peptide. The anxiolytic-like effects of NPS were slightly reduced by SHA 68 in the mouse open field, fully prevented in the rat elevated plus maze and partially antagonized in the rat defensive burying paradigm. Finally, SHA 68 was found poorly active in antagonizing the NPS inhibitory effect on palatable food intake in rats. In all assays SHA 68 did not produce any effect per se. In conclusion, the present study demonstrated that SHA 68 behaves as a selective NPSR antagonist that can be used to characterize the in vivo actions of NPS. However the usefulness of this research tool is limited by its poor pharmacokinetic properties.
Ruzza
Chiara
C
Department of Experimental and Clinical Medicine, Section of Pharmacology and Neuroscience Center and National Institute of Neuroscience, University of Ferrara, via Fossato di Mortara 19, 44100 Ferrara, Italy.
Rizzi
Anna
A
Trapella
Claudio
C
Pela'
Michela
M
Camarda
Valeria
V
Ruggieri
Valentina
V
Filaferro
Monica
M
Cifani
Carlo
C
Reinscheid
Rainer K
RK
Vitale
Giovanni
G
Ciccocioppo
Roberto
R
Salvadori
Severo
S
Guerrini
Remo
R
Calo'
Girolamo
G
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology; D002460:Cell Line; D004435:Eating / Q000187:drug effects; D005106:Exploratory Behavior / Q000187:drug effects; D006801:Humans; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D009479:Neuropeptides / Q000494:pharmacology*; D023303:Oxazolidinones / Q000494:pharmacology*; D011719:Pyrazines / Q000494:pharmacology*; D051381:Rats; D018013:Receptors, Neuropeptide / Q000037:antagonists & inhibitors*
C529493:3-oxo-1,1-diphenyltetrahydrooxazolo(3,4-a)pyrazine-7-carboxylic acid 4-fluorobenzylamide; D014151:Anti-Anxiety Agents; D009479:Neuropeptides; D023303:Oxazolidinones; D011719:Pyrazines; D018013:Receptors, Neuropeptide; D002110:Caffeine