Osmotically driven shape transformations in axons.
We report a cylindrical-peristaltic shape transformation in axons exposed to a controlled osmotic perturbation. The peristaltic shape relaxes and the axon recovers its original geometry within minutes. We show that the shape instability depends critically on the swelling rate and that volume and membrane area regulation are responsible for the shape relaxation. We propose that volume regulation occurs via leakage of ions driven by elastic pressure, and analyze the peristaltic shape dynamics taking into account the internal structure of the axon. The results obtained provide a framework for understanding peristaltic shape dynamics in nerve fibers occurring in vivo.
Experimentalphysik I, University of Bayreuth, D-95440, Bayreuth, Germany.
Pramod A
PA
Pullarkat
Paul
P
Dommersnes
Pablo
P
Fernández
Jean-François
JF
Joanny
Albrecht
A
Ott
D000818:Animals; D001369:Axons / Q000502:physiology*; D001693:Biological Transport, Active; D048430:Cell Shape; D002642:Chick Embryo; D007425:Intracellular Membranes / Q000378:metabolism; D007477:Ions / Q000378:metabolism; D008959:Models, Neurological; D016501:Neurites / Q000502:physiology; D009997:Osmotic Pressure; D016716:PC12 Cells; D051381:Rats; D014867:Water / Q000378:metabolism
D007477:Ions; D014867:Water