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Organ bath experiments are conventionally used to investigate the physiological actions and effects of hormones and drugs on organ responses. We developed an experimental method to reproduce insulin secretion from isolated rat pancreas preparations, to investigate substances that promote insulin secretion ex vivo. 1,5-anhydro-D-glucitol (1,5-AG) is found in foods, and exists in humans and rodents; however, whether 1,5-AG stimulates insulin secretion remains unclear. This study aimed to assess the effects of short-term 1,5-AG stimulation on insulin secretion in both ex vivo and in INS-1E (rat-derived) cells in vitro. Our results indicated that 1,5-AG had no potency to increase the proportion of insulin outflow both in ex vivo and in vitro experiments. Insulin outflow significantly increased upon stimulation with 10 μM glimepiride, a member of the sulfonylurea class of drugs, ex vivo. Glucose-stimulated insulin secretion was observed not only in INS-1E cells but also in rat pancreatic preparations. Our findings demonstrated that short-term exposure to 1,5-AG had no effect on insulin secretion in rats.

Background/Aim: We developed an experimental method to reproduce insulin secretion from isolated rat pancreas preparations using an organ bath system. However, secretion of trypsin, another pancreatic enzyme, interferes with insulin production in such systems. We aimed to ascertain the minimum trypsin inhibitor (TI), dose for obtaining a sustained, stable rate of insulin secretion. Materials and Methods: The action of TI (1-10 μg/ml) on pancreatic preparations of male Wistar-Imamichi rats in organ bath experiments was assessed by measuring insulin, amylase, and trypsin activity. Results: The level of insulin outflow remained steady in the TI-treated samples, in contrast to that in the untreated control, where insulin secretion decreased over time. The level of amylase outflow did not change significantly. Trypsin activity was significantly lower in the TI-treated samples than in the control. Conclusion: Even low concentrations of TI can maintain insulin secretion by inhibiting trypsin activity in organ bath experiments. [ABSTRACT FROM AUTHOR]

Propofol is an anesthetic agent suspended in an emulsion system that includes egg yolk lecithin and soybean oil, because of which, there is concern about the use of propofol in patients allergic to these substances. We examined the association between propofol administration and incidence of adverse events in dogs with allergy to egg yolk lecithin and soybean oil. On the basis of the findings of an allergen-specific immunoglobulin E (IgE) test, 14 dogs with high levels (high-IgE group) and 7 dogs with low levels (normal-IgE group) of IgE were selected. Following intravenous administration of propofol, the incidence of anaphylactic reactions and plasma histamine concentrations under general anesthesia maintained with isoflurane throughout surgery were compared between the two groups. The frequency of anaphylactic reactions and plasma histamine concentrations were compared by the chi-square test and Student t-test, respectively. The statistical significance for both tests was set at P<0.05. In the high- and normal-IgE groups, the average frequencies of anaphylactic reactions after propofol administration were 21.4 and 14.3%, and the mean plasma histamine concentrations were 167.9 ± 94.5 nM and 65.7 ± 40.3 nM, respectively. Animals of neither groups experienced shock-like symptoms. These results revealed that propofol might be relatively safe, although careful perioperative anesthesia monitoring and standby protocols are required when using propofol in dogs with a history of allergic diseases or high chicken- or soybean-specific IgE levels. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study which examined the progress of pancreatitis before the onset of diabetes in WBN/Kob leptin receptor gene (Lepr) rat. Topics discussed include the onset of non-insulin-dependent diabetes secondary to pancreatitis, results of histopathology showing intense changes dependent on age such as hemorrhage or hemosiderin deposition and severity of the pancreatitis in homozygous WBN/Kob-Lepr than those of WBN/Kob rats.