Skip to main content


On an early demonstration of the cell boundary theorem


As stated in Prof. Friel’s letter, the paper by Friel and Tsien [1] includes a rigorous demonstration of what I recently called the cell boundary theorem [2].

I proposed the theorem to formalize an old idea, two early versions of which were cited as examples [2]. I regret that I missed the earlier formalism and demonstration.

I am also addressing all corresponding authors who have cited [2] to make them aware of the earlier work.


  1. 1.

    Friel DD, Tsien RW (1992) A caffeine- and ryanodine-sensitive Ca2+ store in bullfrog sympathetic neurones modulates effects of Ca2+ entry on [Ca2+]i. J Physiol 450:217–246

  2. 2.

    Rios E (2010) The cell boundary theorem: a simple law of the control of cytosolic calcium concentration. J Physiol Sci 60:81–84

Download references

Author information

Correspondence to Eduardo Ríos.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Ríos, E. On an early demonstration of the cell boundary theorem. J Physiol Sci 63, 161 (2013).

Download citation


  • Human Physiology
  • Cell Boundary
  • Early Formalism
  • Cell Physiology
  • Early Demonstration