Complex model of the lower urinary tract

Abstract

The complex model of the lower part of the urinary tract is introduced. It consists of the detrusor smooth muscle cell model and the detailed 1D model of the urethra flow. The nerve control is taken into account. In future this model will allow to simulate the influence of different drugs and mechanical obstructions in the bladder neck and urethra. A general muscle model involving the calcium dynamics in the smooth muscle cell and the growth and remodelling theory will be shortly introduced. For the modelling calcium dynamics the approach of Koenigsberger published in Biophysical Journal (Koenigsberger, M., Sauser, R., Seppey, D., Beny, J.-L., Meister, J.-J., Calcium dynamics and vosomotion in arteries subject to isometric, isobaric and isotonic conditions, Biophysical Journal 95 (2008) 2 728–2 738.) was adopted. The model includes the ATP consumption calculation according to Hai et al. (Hai, C. M., Murphy, R. A., Adenosine 5’-triphosphate consumption by smooth muscle as predicted by the coupled four-state crossbridge model, Biophysical Journal 61(2) (1992) 530–541.). The main part is devoted to the development of a simple bladder model and the detrusor contraction during voiding together with the detailed model of the urethra flow.