title: Synchronization of period-doubling oscillations in vascular coupled nephrons.
abstract: The mechanisms by which the individual functional unit (nephron) of the kidney regulates the incoming blood flow give rise to a number of nonlinear dynamic phenomena, including period-doubling bifurcations and intra-nephron synchronization between two different oscillatory modes. Interaction between the nephrons produces complicated and time-dependent inter-nephron synchronization patterns. In order to understand the processes by which a pair of vascular coupled nephrons synchronize, the paper presents a detailed analysis of the bifurcations that occur at the threshold of synchronization. We show that, besides infinite cascades of saddle-node bifurcations, these transitions involve mutually connected cascades of torus and homoclinic bifurcations. To illustrate the broader range of occurrence of this bifurcation structure for coupled period-doubling systems, we show that a similar structure arises in a system of two coupled, non-identical Rössler oscillators.
authors.affiliation: Department of Physics, The Technical University of Denmark, 2800 Lyngby, Denmark. laugesen@fysik.dtu.dk
authors.forename: J L
authors.initials: JL
authors.lastname: Laugesen
authors.forename: E
authors.initials: E
authors.lastname: Mosekilde
authors.forename: N-H
authors.initials: NH
authors.lastname: Holstein-Rathlou
mesh_terms: D000818:Animals; D025461:Feedback, Physiological; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000502:physiology; D008954:Models, Biological; D009399:Nephrons / Q000098:blood supply* / Q000502:physiology*; D009991:Oscillometry; D011312:Pressure; D051381:Rats; D013997:Time Factors