Résumé
The dorsal root ganglia contain a variety of sensory neurons that transduce somatic stimuli. Following peripheral nerve injury, sensory neurons have to adapt to a new environment in order to successfully promote their axonal elongation. Unsuccessful regeneration leads to post-traumatic neuropathies, such ataxia and pain-related behavior, which are often chronic and mostly resistant to current treatments. Understanding the cellular and molecular mechanisms leading to improved neurite re-growth is a major step to propose a new therapy for nerve repair. It has been demonstrated that a prior in vivo nerve injury enhances both peripheral and central axonal regeneration following a second injury. In vitro, the neurons conditioned by the first traumatism display a faster, elongated mode of neurite growth called regenerative growth. The neuronal growth cone is a highly motile mechanosensitive structure at the tip of the axon. Elasticity is a determining parameter of membrane mechanical properties and provides important information toward the health and function of the cell. Interestingly, it has been shown that membrane tension influences growth cones dynamics. We have investigated, using DIC and AFM, the morphology and the membrane mechanical properties of adult sensory neurons from mice DRG following left sciatic nerve injury.