Nitric oxide synthesis and cGMP production is important for neurite growth and synapse remodeling after axotomy.

Nitric oxide (NO) is an important signaling molecule with a variety of functions in the CNS, including a potential role in modulating neuronal growth and synapse formation. In the present study, we used tractable, identified neurons in the CNS of the pond snail Lymnaea stagnalis to study the role of endogenous NO signaling in neuronal growth and synaptic remodeling after nerve injury. Axonal damage of L.

Manipulations of spinal cord excitability evoke developmentally-dependent compensatory changes in the lamprey spinal cord.

We have examined homeostatic or compensatory plasticity evoked by tonic changes in spinal cord excitability in the lamprey, a model system for investigating spinal cord function. In larval animals, reducing excitability by incubating in tetrodotoxin or the glutamate receptor antagonists CNQX or CNQX/AP5 for 20-48 h resulted in a diverse set of cellular and synaptic changes that together were consistent with an increase in spinal cord excitability. Similar changes occurred to a tonic increase in excitation evoked by incubating in high potassium physiological solution (i.

Locomotor recovery after spinal cord lesions in the lamprey is associated with functional and ultrastructural changes below lesion sites.

While axonal regeneration continues to be the major focus of research into spinal injury, there is growing evidence for changes in functional properties below lesion sites. In this study we have used the lamprey, a model system for studying axonal regeneration after spinal injury, to examine whether functional and ultrastructural changes below lesion sites might also contribute to the recovery of locomotor function in this system. In the current study, the majority of the animals showed good functional recovery 10 weeks after lesioning, even when there was no physiological evidence for regeneration across the lesion site (although animals that recovered poorly always lacked regeneration).