Neurité

Neurite is a term used in neuroscience to denote any projection that extends from a neuron, including axons and dendrites. The word comes from neuron, the basic nerve cell, together with the suffix -ite, indicating a process or projection.

Neurites are essential for neuronal communication. Dendrites typically receive synaptic inputs from other neurons, while axons conduct impulses away from the cell body to target neurons or effector tissues. The size, branching, and electrical properties of neurites shape the structure and function of neural circuits.

In development, neuritogenesis refers to the growth and elaboration of neurites. Growth cones at the tips explore the extracellular environment, guided by chemical cues and contact signals. Cytoskeletal dynamics, especially actin and microtubules, drive extension and steering.

Cultured neurons commonly extend neurites, and neurite outgrowth assays are used to study neuronal growth, injury response, and drug effects. Neurite morphology can be altered by injury, disease, or genetic factors, reflecting underlying cellular states.

In neurodegenerative diseases, dystrophic neurites may form around plaques or other lesions, and changes in neurite density or structure are often used as neuropathological markers.

Neurites are a general term for neuronal projections; distinguishing axons from dendrites is crucial for understanding connectivity, since their roles in signaling are complementary (output versus input). The term emphasizes cellular extensions rather than the soma.