Applied Mathematics Colloquium: Dr. Patrick Fletcher
NIH/NIDDK
Friday, December 8, 2017 · 2 - 3 PM
Title: Modeling spontaneous and stimulated electrical activity in pituitary
corticotroph cells
Speaker: Patrick Fletcher, NIH/NIDDK
Abstract: The electrical activity and calcium dynamics of pituitary corticotroph
cells has been recently demonstrated to be strikingly diverse, both
spontaneously and in response to the agonists corticotropin-releasing hormone
(CRH) and arginine vasopressin (AVP). These cells typically fire tall, sharp
action potentials when spontaneously active, but a variety of other spontaneous
patterns have also been reported, including various modes of bursting. We
demonstrate this diversity with electrophysiological measurements and use
mathematical modeling to investigate its possible sources. The model is
explored using fast-slow analysis and GPU-accelerated numerical simulations. In
the model, variation in as few as two parameters can give rise to many of the
types of patterns observed in electrophysiological recordings. We compare the
known mechanisms for CRH, AVP, and glucocorticoid actions, showing how the
context of the cell's ionic conductances dictates the effects of
agonists.