BETA CELL OSCILLATORY RESPONSE IS NOT RESULT OF A SINGLE COMPONENT ACTION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 与细胞内钙离子振荡平行的脉动胰岛素输出，反映了细胞内对分泌燃料的振荡新陈代谢。我们质疑振荡周期是否保守或随刺激而变化，糖酵解是否对振荡反应的表现是必需的，营养过剩的环境是否影响振荡规律性。我们已经确定，细胞内振荡的钙离子模式与所用的分泌燃料类型(葡萄糖、丙酮酸甲酯(MEP)、异丙酮酸酮酯(KIC))无关。因此，无论刺激燃料的类型如何，单细胞在重复刺激时都会以相同的模式做出反应。亚刺激性(4 MM)葡萄糖的存在不是获得MEP或KIC振荡反应的必要条件。几个小时的葡萄糖剥夺(细胞在亚刺激浓度的MEP存在的情况下培养)并没有阻止燃料刺激的振荡反应，也没有阻止胰岛素的分泌。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Pulsatile insulin output, paralleled by oscillations in intracellular Ca2+, reflects oscillating metabolism within ¿-cell in response to secretory fuels. We questioned whether oscillatory periodicity is conserved or varied from stimulation to stimulation, whether glycolysis is essential for the manifestation of the oscillatory response and whether the environment of nutrient oversupply affects oscillatory regularity. We have determined that a ¿-cell oscillatory Ca2+ pattern is independent of the type of applied secretory fuel (glucose, methyl-pyruvate (MeP), ¿-ketoisocaproate (KIC). Single cells thus respond with the same pattern when repeatedly stimulated, regardless of the type of stimulatory fuel. Presence of sub-stimulatory (4 mM) glucose was not necessary to obtain oscillatory response to MeP or KIC. Several hours of glucose deprivation (cells were cultured in the presence of sub-stimulatory concentration of MeP), did not prevent fuel-stimulated oscillatory response, nor insulin secretion.