Chaos in a System of Interacting Nephrons
Urine is formed from blood by a process of filtration followed by selective reabsorption and secretion. The basic functional unit is the nephron of which there are about 30,000 in a rat kidney (1 million in a human kidney).
Recent experimental results have revealed an oscillatory behaviour of the proximal intratubular pressure in rat nephrons with a typical period of 20–30 sec. The oscillations are assumed to arise from temporal self-organisation in the glomerular filtration of the individual nephron. While for normal rats these oscillations have a well-defined frequency and amplitude, highly irregular oscillations are observed for spontaneously hypertensive rats.
We present some simulation results from models of non-interacting as well as coupled nephrons and compare these with results from analysis of experimental data.
KeywordsPhase Portrait Correlation Dimension Pressure Oscillation Afferent Arteriole Irregular Oscillation
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