Journal of Computational Neuroscience

, Volume 15, Issue 3, pp 367–389 | Cite as

AHP's, HAP's and DAP's: How Potassium Currents Regulate the Excitability of Rat Supraoptic Neurones

  • Peter Roper
  • Joseph Callaway
  • Talent Shevchenko
  • Ryoichi Teruyama
  • William Armstrong


We have constructed mathematical models of the electrical activity of two hypothalamic supraoptic neuro-secretory cell-types, and we support our models with new calcium imaging and in vitro electrophysiological data. These cells are neurones that project to the pituitary gland and secrete either of two hormones, oxytocin or vasopressin, into the blood from their axonal terminals. Oxytocin-secreting and vasopressin-secreting cells are closely related and physically they differ only subtly, however when physiologically stressed their discharge patterns are dramatically distinct. We first show how each potassium current contributes to the action-potentials and after-potentials observed in these cells, and we show how these after-potentials are correlated to intra-cellular calcium elevations. We then show how these currents regulate the excitability of these cells and consequently shape their discharge pattern.


Calcium Potassium Mathematical Model Vasopressin Electrical Activity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • Peter Roper
    • 1
  • Joseph Callaway
    • 2
  • Talent Shevchenko
    • 2
  • Ryoichi Teruyama
    • 2
  • William Armstrong
    • 2
  1. 1.National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of HealthBethesdaUSA
  2. 2.Department of Anatomy and NeurobiologyUniversity of Tennessee College of MedicineMemphisUSA

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