Investigation of the syncytial nature of detrusor smooth muscle as a determinant of action potential shape

Research output: Chapter in Book/Report/Conference proceedingChapter


  • Shailesh Appukuttan
  • Mithun Padmakumar
  • John Young
  • Keith Brain
  • Rohit Manchanda

Colleges, School and Institutes

External organisations

  • University of Portsmouth


Unlike most excitable cells, certain syncytial smooth muscle cells are known to exhibit spontaneous action potentials of varying shapes and sizes. These differences in shape are observed even in electrophysiological recordings obtained from a single cell. The origin and physiological relevance of this phenomenon are currently unclear. The study presented here aims to test the hypothesis that the syncytial nature of the detrusor smooth muscle tissue contributes to the variations in the action potential profile by influencing the superposition of the passive and active signals. Data extracted from experimental recordings have been compared with those obtained through simulations. The feature correlation studies on action potentials obtained from the experimental recordings suggest the underlying presence of passive signals, called spontaneous excitatory junction potentials (sEJPs). Through simulations, we are able to demonstrate that the syncytial organization of the cells, and the variable superposition of the sEJPs with the “native action potential”, contribute to the diversity in the action potential profiles exhibited. It could also be inferred that the fraction of the propagated action potentials is very low in the detrusor. It is proposed that objective measurements of spontaneous action potential profiles can lead to a better understanding of bladder physiology and pathology

Bibliographic note

H., Dierckx, Fenton, F. H., Filippi, S., Pumir, A., Sridhar, S., eds. (2019). Simulating Normal and Arrhythmic Dynamics: From Sub-Cellular to Tissue and Organ Level. Lausanne: Frontiers Media. doi: 10.3389/978-2-88963-067-7


Original languageEnglish
Title of host publicationSimulating normal and arrhythmic dynamics: from sub-cellular to tissue and organ level
EditorsHans Dierckx, Flavio H. Fenton, Simonetta Filippi, Alain Pumir
Publication statusPublished - 20 Sep 2019


  • urinary bladder, smooth muscle, detrusor, syncytium, action potentail shape, feature correlation, neuron model