Tension Dependent Growth and Retraction of Neurites

Neurons are cells that carry electrical impulses. The growth of axons in these cells has been of interest for some time. Experiments have been performed to understand the tension dependent growth of axons but there are few models in the literature that can explain the characteristics of axon growth. Here we propose a growth model that is based on diffusion limited polymerization of microtubules in the axon. The tension in the axonal membrane determines the compressive force on the polymerizing microtubules and this controls the rate of growth. We show that the growth process of an axon that is coupled to a device which can measure and apply forces on it can be described by an ordinary differential equation. Solutions of this equation for various loading conditions reproduces the data in many recent experiments.