[Design, synthesis and activities of 4-(2-acetoxybenzoylamino) butyramide derivatives].

To explore new agents of gamma-aminobutyric acid (GABA) derivatives with more potent antiepileptic activity, a series of 4-(2-acetoxybenzoylamino) butyramide derivatives were designed and synthesized. All of the novel compounds (5a-51) were synthesized from GABA as starting material, and their structures were confirmed with IR, 1H NMR, EI-MS and elemental analysis. Preliminary pharmacological test in vitro showed that all target compounds displayed strong antiepileptic activities and were worth for further study. The structure-activity relationship of 4-(2-acetoxybenzoylamino) butyramide derivatives was also discussed preliminarily.

[Design, synthesis and antiepileptic activity of 4-(2-acetoxybenzoylamino) butyrate derivatives].

A series of 4-(2-acetoxybenzoylamino) butyrate derivatives were designed and synthesized. All of the novel 12 compounds (7a-7k) were synthesized from gamma-aminobutyric acid (1) as starting material, and their structures were confirmed with IR, 1H NMR, EI-MS and elemental analysis. Preliminary pharmacological test in vitro showed that most of these title compounds possessed antiepileptic activity. Compounds 7i-7k displayed strong antiepileptic activity and are worth for further development. Compounds 4, 7d-7h showed moderate antiepileptic activity. The structure-activity relationship of 4-(2-acetoxybenzoylamino) butyrate derivatives is also discussed preliminarily.

Central Neuropeptide S inhibits distal colonic transit through activation of central Neuropeptide S receptor in mice.

Neuropeptide S (NPS), the endogenous ligand of NPS receptor (NPSR), regulates many biological functions, including arousal, anxiety, locomotion and food intake. NPSR mRNA is expressed in several regions of central autonomic network through which the brain controls visceromotor and other responses essential for survival. However, the role of NPS/NPSR system in regulating gastrointestinal motor is still unknown. Here, we studied the effects of NPS on distal colonic transit in mice. Intracerebroventricular (i.c.v.) injection of NPS (1-1000 pmol) inhibited fecal pellet output and bead expulsion in a dose-dependent manner. However, intraperitoneal injection of NPS (1000 and 10000 pmol) did not affect fecal pellet output and bead expulsion. In vitro, NPS (0.1-10 microM) also did not modulate distal colonic contractions. Furthermore, i.c.v. co-administration of [D-Val(5)]NPS, a pure and potent NPSR antagonist, dose-dependently antagonized the inhibitory effects of NPS on fecal pellet output and bead expulsion. In conclusion, our results firstly indicate that central NPS inhibits distal colonic transit through the activation of central NPSR, which implicate that NPS/NPSR system might be a new target to treat function disorder of distal colon.

Neuropeptide S facilitates spatial memory and mitigates spatial memory impairment induced by N-methyl-D-aspartate receptor antagonist in mice.

Neuropeptide S (NPS) is a recently discovered peptide shown to be involved in regulating arousal and anxiety. NPS receptor (NPSR) mRNA is expressed significantly in the major input and output regions of hippocampal formation, which are critical in the modulation of learning and memory. However, the role of NPS/NPSR system in regulating of learning and memory is still unknown. Here, we use the Morris water maze (MWM) to determine the effects of NPS on spatial learning and memory following intracerebroventricular (i.c.v.) injection in mice. Our data show that i.c.v. injection of NPS facilitates spatial memory in the MWM without significant alteration of latency to the target and swimming speed. Furthermore, NPS (i.c.v.) mitigates spatial memory impairment induced by the selective N-methyl-d-aspartate receptor antagonist MK801. Taken together, our results firstly demonstrate that NPS facilitates spatial memory and mitigates MK801-induced spatial memory impairment in mice.