Modelling of the possible role of glycolytic oscillations in the rapid
pulsatile insulin secretion by pancreatic beta cells
Nicolas Markadieu(1,2) and Albert Goldbeter (1)
(1)
Unite de Chronobiologie Theorique,
Faculte des Sciences CP 231,
Universite Libre de Bruxelles, B-1050 Brussels, Belgium
(2)
Department of Chemistry and CATS,
University of Copenhagen,
Universitetsparken 5, C108, 2100 Copenhagen O, Denmark
Abstract:
Experimental observations suggest that glycolytic oscillations could
underlie the rapid pulsatile secretion of insulin with a periodicity
of about 13 minutes. Since the b cells within an islet are synchronized by
gap junctions, the question arises as to how b cells from different
islets can synchronize to produce a clearly pulsatile secretion.
Indeed, if it was not the case, each islet could secrete insulin
independently, and give rise to a mean insulin secretion which is constant
in time. Using modelling, we studied the coupling between b cells from
different islets. Our theoretical approach is based on a two-variable
model for the description of the glycolytic oscillations in each of the
islets. We demonstrate that it could be possible to explain the
synchronization by automodulation of the oscillating blood glucose level
induced by the pulsatile insulin secretion.