périkaryon

A perikaryon, also known as a soma, is the cell body of a neuron. It contains the neuron's nucleus and the majority of its organelles, including the endoplasmic reticulum, Golgi apparatus, and mitochondria. The perikaryon is responsible for maintaining the neuron's life and function, synthesizing proteins and other molecules necessary for neurotransmission. It is also the site of integration of synaptic inputs received by the dendrites.

The perikaryon typically has a roughly spherical or pyramidal shape. Extending from the perikaryon are two main types of processes: dendrites and an axon. Dendrites are branched extensions that receive signals from other neurons, while the axon is a single, long projection that transmits signals to other neurons or effector cells. The cytoplasm of the perikaryon is called the neuroplasm and contains neurofilaments and microtubules that contribute to the structural integrity of the cell and aid in the transport of materials within the neuron.

The health and integrity of the perikaryon are crucial for neuronal function and survival. Damage or dysfunction of the perikaryon can lead to various neurological disorders. For instance, in neurodegenerative diseases like Alzheimer's and Parkinson's, the perikaryon undergoes significant pathological changes, including the accumulation of abnormal protein aggregates. Understanding the perikaryon's structure and function is fundamental to comprehending neuronal communication and the basis of neurological diseases.