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

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心机构，不一定为研究者机构。脉冲式胰岛素输出，由细胞内Ca 2+的振荡引起，反映了细胞内响应分泌燃料的振荡代谢。我们质疑振荡周期是否是保守的或不同的刺激，糖酵解是否是必不可少的振荡反应的表现，以及是否营养过剩的环境影响振荡规律。我们已经确定，一个<$-细胞振荡的Ca 2+模式是独立的类型所施加的分泌燃料（葡萄糖，丙酮酸甲酯（MeP），α-酮异己酸（KIC）。因此，无论刺激燃料的类型如何，单细胞在反复刺激时都会以相同的模式做出反应。亚刺激（4 mM）葡萄糖的存在是没有必要获得振荡响应MeP或KIC。几个小时的葡萄糖剥夺（细胞在亚刺激浓度的MeP存在下培养）没有阻止燃料刺激的振荡反应，也没有阻止胰岛素分泌。

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), a-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.