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Carbon cycling and productivity within Weno Island of Micronesia enclosed by the coral reef may be likely self-maintained and insignificantly affected by the open ocean. Therefore, it is important to understand the role of the mangrove known as providing the organic matter and habitats for many organisms in this enclosed area. In order to trace the nutritional source of fauna (mostly invertebrates) in the mangrove forest of Weno island, we analyzed the fatty acid (FA) and carbon and nitrogen stable isotopes of potential nutritional sources (mangrove leaf & pneumatophore, seagrass leaf & root, surface sediment, and particulate organic matter (POM) in water) and consumers (4 gastropods and anomura). The mangrove and seagrass contained the abundance of 18:2ω6, and 18:3ω3, whereas FAs associated with phytoplankton and bacteria were accounted for a high proportion in the surface sediment and POM. FA composition of consumers was found to be similar to those of the surface sediment, mangrove, and seagrass. These were also confirmed through the mixing model of stable isotope for contribution of nutritional sources to consumers. Overall results with the feeding types of investigated mangrove fauna indicate that investigated mangrove fauna obtained their nutrition from the various sources, i.e. the mangrove for Littorina cf. scabra, the microalgae for Strombus sp., and omnivorous Pagurus sp. and Terebralia cf. palustris. However, it is obvious that the nutrition of most species living in the mangrove ecosystem is highly dependent on the mangrove, either directly or indirectly. More detail food-web structure and function of the mangrove ecosystem would be established with the analysis of additional fauna and flora. [ABSTRACT FROM AUTHOR]

Background/Aims Histamine-2 receptor antagonists (H2RA) are used to treat acid-related disorders and functional dyspepsia. In contrast to other H2RAs, nizatidine promotes gastric emptying (GE). We investigated the effects of nizatidine and famotidine on intragastric pH and the GE rate in rats exposed to stress. Materials and Methods We used 8-week-old male Wistar rats. Based on administration of water or drugs after an overnight fast, the animals were categorized into the nonstress-water, stress-water, stress-nizatidine, stress-famotidine, and stress-nizatidine with mosapride groups. The rats had access to pre-weighed food for 10 minutes, and those in the stress groups were exposed to 1 hour of restraint stress. Intragastric pH was measured under isoflurane anesthesia, and the GE rate was measured after the rats were sacrificed. Results The GE rate was significantly lower in the stress-water and stress-famotidine groups than in the nonstress-water group. However, GE in the stress-nizatidine and stress-nizatidine with mosapride group did not significantly differ from that in the nonstress- water group. The GE rate was significantly higher in the stress-nizatidine with mosapride than in the stress-famotidine group. Intragastric pH was significantly higher in the stress-nizatidine and stress-famotidine groups than in the stress-water group. Nonetheless, there was no significant difference in pH between the stress-nizatidine and stress-famotidine groups. The intragastric pH was slightly but significantly higher in the stress-nizatidine with mosapride group than in the stress-nizatidine and stress-famotidine groups. Conclusions In contrast to famotidine, nizatidine prevents stress-induced GE delay, which suggests that nizatidine is superior to other H2RAs for treatment of functional dyspepsia associated with delayed GE.

Background/Aims Studies in healthy humans have reported that the addition of mosapride to acid suppressants resulted in higher intragastric pH than acid suppressant administration alone. We investigated the effect of the addition of mosapride to famotidine on the intragastric pH and gastric emptying rate (GER) in rats. Materials and Methods Sixty male Wistar rats were used in this study. Experimental groups were divided into control, famotidine-only, mosapride-only, and famotidine with mosapride (combination). The first experiment was performed in non-stressed rats. Mosapride was administered by oral gavage 1 hour before the meal, and famotidine was administered just before the meal. The rats were provided with food for 30 minutes. The intragastric pH was measured under isoflurane anesthesia, and the GER was measured after harvesting the stomach. In the stress experiment, rats were exposed to 1-hour restraint stress immediately after mosapride administration and subjected to the same process as in the experiment with the non-stressed rats. Results The famotidine-only and combination groups showed significantly higher gastric pH levels than the control group in non-stressed (P

Background/Aims: Stress has a role in the pathogenesis of functional dyspepsia (FD) and influences food intake in humans and animals. Prokinetic drugs have been used in FD, and some of these drugs reverse the feeding inhibition (FI) induced by acute restraint stress in rats. We aimed to evaluate the effect of DA-9701 on FI induced by acute restraint in rats. Materials and Methods: Male Sprague-Dawley rats were divided into 6 groups: Control (no stress), Stress+vehicle, and Stress+DA-9701 at doses of 1, 3, 10, and 30 mg/kg (n=6∼7). DA-9701 or vehicle was administered through gastric gavage 45 minutes before stress. After 60 minutes of stress, pre-weighed chow was given and the weight of remaining food was measured 30 and 60 minutes later. The effect of DA-9701 on FI was compared after pretreatment with WAY100635, a 5HT1A antagonist. Results: The restraint stress group had significantly less food intake than the control group. After feeding, rats given 1 and 3 mg/kg of DA-9701 showed increased food intake at 60 minutes, but this was not statistically significant. Rats given 10 mg/kg of DA-9701 showed significantly increased food intake at 30 minutes and 60 minutes (P＜0.05). Interestingly, rats given 30 mg/kg of DA-9701 showed a significant decrease in food intake, similar to that of the vehicle group. The beneficial effect of 10 mg/kg of DA-9701 on FI was abolished by the pretreatment with WAY100635. Conclusions: Acute restraint stress reduced food intake in rats and pretreatment with DA-9701 improved stress-induced FI.