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Understanding the long-term impact of scientific findings requires understanding the dynamic process of new research fields' formation. In new research fields, slow-cited papers (SCP) and the awakeners (AW) are more likely to exist, indicating explorers revisited underrated but significant past papers relocating the findings in the new paradigm. This study acquired SCP-AW pairs located in the integrated point of two different research fields using the inheritance of clusters. We found that research field integration, including SCP-AW pairs, was diverse but followed a similar pattern throughout history, generating an equal mix of SCP and AW fields. The recent trend toward more AW-centric disciplinary combinations supports the belief that field integration will become increasingly technology-driven in the coming years.

Nesfatin-1 is an anorectic peptide expressed in both peripheral tissues and brain areas involved in the regulation of feeding, emotion and emesis. The aim of the present study is to characterize the distribution of NUCB2/nesfatin-1 in Suncus murinus and to investigate the actions of nesfatin-1 to affect gastrointestinal contractility, emesis, food and water intake, and locomotor activity. The deduced amino acid sequence of S. murinus nesfatin-1 using in silico cloning showed high homology with humans and rodents. NUCB2 mRNA was detected throughout the entire brain and in the gastrointestinal tract, including the stomach and gut. Western blot analysis and immunohistochemistry confirmed the expression of nesfatin-1 protein in these regions. The NUCB2 mRNA levels in the hypothalamus, hippocampus and brainstem were significantly decreased, whereas that in the striatum were increased after 24 h starvation compared to ad libitum-fed animals (p < 0.05). In in vitro studies, nesfatin-1 (0.3–1,000 pM) failed to contract or relax the isolated gastric antrum and intestinal segments. In conscious, freely moving animals, intracerebroventricular administration of nesfatin-1 (1–50 pmol) induced emesis (p < 0.05) and suppressed 6-h cumulative food intake (p < 0.05), without affecting the latency to feeding. Nesfatin-1 (25 pmol, i.c.v.) decreased 24-h cumulative food and water intake by 28.3 and 35.4%, respectively (p < 0.01). No significant differences in locomotor activity were observed. In conclusion, NUCB2/nesfatin-1 might be a potent regulator of feeding and emesis in S. murinus. Further studies are required to elucidate the mechanism of actions of this peptide as a mediator linking the brainstem NUCB2/nesfatin-1 to forebrain system.

Gastric contractions show two specific patterns in many species, migrating motor contractions (MMC) and postprandial contractions (PPCs), that occur in the fasted and fed states, respectively. In this study, we examined the role of somatostatin (SST) in gastric motility both in vivo and in vitro using the Asian house shrew (Suncus murinus). We performed in vivo recordings of gastric motility and in vitro organ bath experiments using S. murinus, which was recently established as a small laboratory animal for use in tests of gastrointestinal motility. SST (1.65 µg kg−1 min−1) was intravenously administered during phase II of MMC and PPCs. Next, the effect of SST on motilin-induced gastric contractions at phase I of MMC was measured. Cyclosomatostatin (CSST), an SST receptor antagonist, was administered at the peak of phase III of MMC. In addition, the effect of SST (10−11–10−9 M) on motilin-induced gastric contractions was evaluated using an organ bath experiment in vitro. In conscious, free-moving S. murinus, the administration of SST decreased the occurrence of the spontaneous phase II of MMC and PPCs. Pretreatment with SST and octreotide suppressed the induction of motilin-induced gastric contractions both in vivo and in vitro. Administration of CSST before the peak of spontaneous phase III contractions had no effect on gastric contractions. Endogenous SST is not involved in the regulation of gastric MMC and PPCs, but exogenous SST suppresses spontaneous gastric contractions. Thus, SST would be good for treating abnormal gastrointestinal motility disorders.