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

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Abstract

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.

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Authors and Affiliations

  1. National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA

    Peter Roper

  2. Department of Anatomy and Neurobiology, University of Tennessee College of Medicine, 855 Monroe Avenue, Memphis, TN, 38163, USA

    Joseph Callaway, Talent Shevchenko, Ryoichi Teruyama & William Armstrong

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  1. Peter Roper
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  2. Joseph Callaway
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  3. Talent Shevchenko
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  4. Ryoichi Teruyama
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  5. William Armstrong
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Roper, P., Callaway, J., Shevchenko, T. et al. AHP's, HAP's and DAP's: How Potassium Currents Regulate the Excitability of Rat Supraoptic Neurones. J Comput Neurosci 15, 367–389 (2003). https://doi.org/10.1023/A:1027424128972

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