title: In vitro and in vivo pharmacological characterization of a neuropeptide S tetrabranched derivative.
abstract: The peptide welding technology (PWT) is a novel chemical strategy that allows the synthesis of multibranched peptides with high yield, purity, and reproducibility. With this approach, a tetrabranched derivative of neuropeptide S (NPS) has been synthesized and pharmacologically characterized. The in vitro activity of PWT1-NPS has been studied in a calcium mobilization assay. In vivo, PWT1-NPS has been investigated in the locomotor activity (LA) and recovery of the righting reflex (RR) tests. In calcium mobilization studies, PWT1-NPS behaved as full agonist at the mouse NPS receptor (NPSR) being threefold more potent than NPS. The selective NPSR antagonists [ (t) Bu-D-Gly(5)]NPS and SHA 68 displayed similar potency values against NPS and PWT1-NPS. In vivo, both NPS (1-100 pmol, i.c.v.) and PWT1-NPS (0.1-100 pmol, i.c.v.) stimulated mouse LA, with PWT1-NPS showing higher potency than NPS. In the RR assay, NPS (100 pmol, i.c.v.) was able to reduce the percentage of mice losing the RR after diazepam administration and their sleep time 5 min after the i.c.v. injection, but it was totally inactive 2 h after the injection. On the contrary, PWT1-NPS (30 pmol, i.c.v.), injected 2 h before diazepam, displayed wake-promoting effects. This PWT1-NPS stimulant effect was no longer evident in mice lacking the NPSR receptor. The PWT1 technology can be successfully applied to the NPS sequence. PWT1-NPS displayed in vitro a pharmacological profile similar to NPS. In vivo PWT1-NPS mimicked NPS effects showing higher potency and long-lasting action.
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Ruzza
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Rizzi
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Malfacini
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Alice
authors.initials: A
authors.lastname: Pulga
authors.affiliation: Department of Chemical and Pharmaceutical Sciences and LTTA, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Pacifico
authors.affiliation: Department of Chemical and Pharmaceutical Sciences and LTTA, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Severo
authors.initials: S
authors.lastname: Salvadori
authors.affiliation: Department of Chemical and Pharmaceutical Sciences and LTTA, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Trapella
authors.affiliation: Department of Pharmaceutical Sciences, University of California Irvine Irvine, California, 92697.
authors.forename: Rainer K
authors.initials: RK
authors.lastname: Reinscheid
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Girolamo
authors.initials: G
authors.lastname: Calo
authors.affiliation: Department of Chemical and Pharmaceutical Sciences and LTTA, University of Ferrara 44121, Ferrara, Italy.
authors.forename: Remo
authors.initials: R
authors.lastname: Guerrini
keywords: Calcium mobilization; PWT-NPS; locomotor activity; mice; neuropeptide S; neuropeptide S receptor; righting reflex