Intercellular Ca2+ waves sustain coordinate insulin secretion in pig islets of Langerhans.
Insulin release was investigated in parallel with changes in cytosolic calcium concentration, [Ca2+]i, in pig islets stimulated by glucose. After two days in culture, glucose stimulation failed to induce insulin release, and caused limited [Ca2+]i changes in few cells. After ten days, insulin response was partially restored and [Ca2+]i recordings revealed a slow oscillatory activity of the whole islet. Slow oscillations appeared to be due to the average [Ca2+]i variations resulting from the spreading of waves throughout the islet. These waves demonstrate the reestablishment of functional cell coupling, which appears to play a critical role in insulin release.
Bertuzzi
F
F
Medicine Department, DIBIT, San Raffaele Scientific Inst., Milano, Italy.
Zacchetti
D
D
Berra
C
C
Socci
C
C
Pozza
G
G
Pontiroli
A E
AE
Grohovaz
F
F
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D005456:Fluorescent Dyes; D016257:Fura-2; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008856:Microscopy, Fluorescence; D018715:Microscopy, Video; D009991:Oscillometry; D013552:Swine
D005456:Fluorescent Dyes; D007328:Insulin; D005947:Glucose; D002118:Calcium; D016257:Fura-2