Cooperative phase dynamics in coupled nephrons

The individual functional unit of the kidney (the nephron) displays oscilla tions in its pressure and flow regulation at two different time scales: Rel atively fast oscillations associated with the myogenic dynamics of the affe rent arteriole, and slower oscillations related with a delay in the tubulog lomerular feedback. Neighboring nephrons interact via vascularly propagated signals. We study the appearance of various forms of coherent behavior in a model of two such interacting nephrons. Among the observed phenomena are in-phase and anti-phase synchronization of chaotic dynamics, multistability , and partial phase synchronization in which the nephrons attain a state of chaotic phase synchronization with respect to their slow dynamics, but the fast dynamics remains desynchronized.