Modeling neurite outgrowth on laminin in vitro

Experimental parameters were measured and incorporated into a mathematical model to describe axonal outgrowth on the extracellular matrix molecule, laminin, in vitro. To elucidate the role of laminin and other basement membrane components in axonal growth and guidance, a systematic analysis of the effects of these various molecules on outgrowth characteristics such as the rate and direction of growth is required. Ideal parameters for measuring these characteristics appear to be the root-mean-square speed, s, and the directional persistence time, P, of the growing axon tip. These quantities were measured for neurons obtained from the superior cervical ganglia of one day-old neonatal rats, mechanically dissociated into single cells and cultured in serum-free medium. To illustrate the potential effects of the observed concentration dependence of these parameters on axonal outgrowth, the ability of an axon to traverse a laminin substrate was examined using a hypothetical model for the axon trajectory based on the measured s and P