Corticosteroids are used in the treatment of many diseases; however, they also induce various side effects. Dexamethasone is one of the most potent corticosteroids, and it has been reported to induce the side effect of impaired salivary gland function. This study aimed to evaluate the effects of dexamethasone on mouse submandibular gland function to gain insight into the mechanism of dexamethasone-induced salivary hypofunction. The muscarinic agonist carbachol (CCh) induced salivary secretion and was not affected by short-term dexamethasone treatment but was decreased following long-term dexamethasone administration. The expression levels of the membrane proteins Na+-K+-2Cl− cotransporter, transmembrane member 16A, and aquaporin 5 were comparable between the control and long-term dexamethasone treatment groups. The CCh-induced increase in calcium concentration was significantly lower in the presence of extracellular Ca2+ in the long-term dexamethasone treatment group compared to that in the control group. Furthermore, CCh-induced salivation in the absence of extracellular Ca2+ and Ca2+ ionophore A23187-induced salivation was comparable between the control and long-term dexamethasone treatment groups. Moreover, salivation induced by the Ca2+-ATPase inhibitor thapsigargin was diminished in the long-term dexamethasone treatment group. In summary, these results demonstrate that short-term dexamethasone treatment did not impair salivary gland function, whereas long-term dexamethasone treatment diminished store-operated Ca2+ entry, resulting in hyposalivation in mouse submandibular glands.

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Long‐term climate monitoring by universities provides fundamental data for various disciplines in the natural sciences. Kyoto University once managed 10 university forest stations and is currently managing five. At these stations, climate data have been monitored almost since the establishment of each station until today, with the exception of the stations in foreign countries. We compiled and report the monthly climate data at these forest stations from the start of monitoring until December 2018. These data are important for investigating environmental changes in East Asia, including China (Taiwan), South Korea (Chosen) and Russia (Sakhalin, Karafuto) over the last 100 years. Long‐term monitoring often involves minor and major changes in the monitoring procedures, devices and even monitoring sites due to unavoidable circumstances, such as technological advances, changes in standard methods and climatic and anthropogenic disasters. Therefore, associated metadata on the monitoring methods are also important. We also compiled metadata on changes in monitoring methods. In addition, to examine the effects of changes in the methods on the observed climate data, we compared the values recorded before and after the change for each climate variable at each monitoring site. Methodological changes affected only a few variables, with the exception of humidity. Careful interpretation may be required when a researcher uses humidity data in any analysis. The complete data set for this abstract published in the Data Paper section of the journal is available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2020-03.1/jalter-en.

Background: Hypofunction of different organs in the body is associated with diabetes, including in the oral cavity. Diabetes is often associated with xerostomia, but the underlying mechanism is not well characterized. Thus, the mechanisms underlying diabetes-induced xerostomia were investigated in this study in KK-A y mice as an experimental model of type 2 diabetes. Methods: The mechanisms involved in diabetes-induced xerostomia were investigated using the ex vivo glandular perfusion technique, histological analysis, and immunohistochemical and intracellular signaling analyses. Results: Ex vivo submandibular gland secretions from KK-A y mice decreased by 30% following stimulation with 0.3 μmol/L carbachol (CCh), a cholinergic agonist. Acinar cell weight was comparable between KK-A y and control mice, whereas duct cell weight was significantly greater in KK-A y mice. Concentrations of Na + and Cl − in the secreted saliva decreased significantly in KK-A