Nanomechanics of Mice Sensory Neurons as Measured by Atomic Force Microscopy

We use atomic force microscopy (AFM) to study the morphological and nanomechanical properties of mice dorsal root ganglia sensory neurons in regenerative growth mode. A prior peripheral nerve injury in vivo, promotes a rapid elongated mode of sensory neurons neurite regrowth in vitro. Complementary differential interference contrast microscopy results show that conditioned axotomy, induced by sciatic nerve injury, did not increase somatic size of adult lumbar sensory neurons but promoted the appearance of larger growth cones. Our AFM data indicate that neurons having a regenerative growth are characterized by softer growth cones, compared to control neurons. The increase of the growth cone membrane elasticity suggests a modification in the ratio and the inner framework of the main structural proteins.