Glucose increases activity and Ca2+ in insulin-producing cells of adult Drosophila.
We sought to understand the mechanisms underlying glucose sensing in Drosophila melanogaster. We found that insulin-producing cells (IPCs) of adult Drosophila respond to glucose and glibenclamide with a burst-like pattern of activity. Under controlled conditions IPCs have a resting membrane potential of -62+/-4 mV. In response to glucose or glibenclamide, IPCs generate action potentials at a threshold of -36+/-1.4 mV with an amplitude of 46+/-4 mV and width of 9.3+/-1.8 ms. Real-time Ca imaging confirms that IPCs respond to glucose and glibenclamide with increased intracellular Ca. These results provide the first detailed characterization of electrical properties of IPCs of adult Drosophila and suggest that these cells sense glucose by a mechanism similar to mammalian pancreatic β cells.
Kréneisz
Orsolya
O
Departments of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut 06269, USA.
Chen
Xinnian
X
Fridell
Yih-Woei C
YW
Mulkey
Daniel K
DK
D000818:Animals; D002118:Calcium / Q000502:physiology*; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D004331:Drosophila melanogaster / Q000166:cytology* / Q000378:metabolism* / Q000502:physiology; D005947:Glucose / Q000378:metabolism* / Q000494:pharmacology; D005905:Glyburide / Q000494:pharmacology; D006706:Homeostasis / Q000187:drug effects / Q000502:physiology; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D054086:KATP Channels / Q000187:drug effects / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D023421:Models, Animal
D007004:Hypoglycemic Agents; D007328:Insulin; D054086:KATP Channels; D005947:Glucose; D005905:Glyburide; D002118:Calcium