Effect of intracellular delivery of energy metabolites on intracellular Ca2+ in mouse islets of Langerhans

Autor: Kerstin Nolkrantz, Gabriella M. Dahlgren, Robert T. Kennedy
Rok vydání: 2005
Předmět:
Zdroj: Life Sciences. 77:2986-2997
ISSN: 0024-3205
Popis: Regulation of glucose-induced oscillations in intracellular Ca2+ concentration ([Ca2+]i) was investigated by using a novel technique, electroporation from an electrolyte-filled capillary, to deliver energy metabolites to the intracellular compartment of mouse islets. Intracellular application of ATP resulted in a nifedipine-sensitive increase in [Ca2+]i, consistent with a KATP-channel dependent mechanism of Ca2+ influx. [Ca2+]i in islets exposed to 10 mM glucose oscillated with a period of approximately 3 min, often superimposed with faster oscillations. Electroporation of ATP blocked all types of oscillations and elevated [Ca2+]i while delivery of ADP had no effect on oscillations. Intracellular delivery of glucose-6-phosphate or fructose-1,6-bisphosphate tended to transform slow oscillations to fast oscillations. These results demonstrate that modulation of ATP concentrations and glycolytic flux are important in development of slow oscillations.
Databáze: OpenAIRE