Similarities of K+ATP channel expression and Ca2+ changes in pancreatic beta cells and hypothalamic neurons.

The mechanisms through which pancreatic beta cells recognize and respond to changes in circulating glucose are well understood. Evidence is accumulating that a subpopulation of neurons in the ventromedial hypothalamus (VMH) use similar cellular mechanisms to sense changes in extracellular glucose. In the present study, we used PCR and single-cell calcium imaging techniques to investigate whether glucose-sensing cells in the pancreas and hypothalamus employ a similar set of stimulus-response elements. Dispersed cells from mouse pancreata and hypothalamus were used in conjunction with the insulin-secreting cell line MIN6. We present functional data suggesting that both pancreatic and a subpopulation of hypothalamic cells exhibit glucose- and tolbutamide-evoked changes in cytosolic calcium and consider some clinical implications of different glucose sensors using the same mechanisms.