The figure shows a section of the gray matter of the brain.
A large multipolar neuron stands out in the center of the image. Its cell body, also called the perikaryon, and several processes extending from it are highlighted in green.
The nucleus of the large neuron is highlighted in light blue. It contains loosely arranged chromatin, which gives the nucleus a relatively pale appearance. A large nucleolus, highlighted in dark blue, is also clearly visible.
Two other neurons, also highlighted in green, can be seen in the image. They can be recognized by their characteristic staining, their processes, and the appearance of their nuclear chromatin.
The nucleus of the large neuron is highlighted in light blue. It contains loosely organized chromatin and one or more large nucleoli, highlighted in dark blue.
Two other neurons, also highlighted in green, can be seen in the image. They can be recognized by their characteristic staining, the processes extending from their cell bodies, and the appearance of their nuclear chromatin.
In addition to the neurons described above, the image contains many smaller nuclei, most likely belonging to neuroglial cells (glial cells). Their nuclei are highlighted in dark blue. Routine hematoxylin and eosin (H&E) staining does not reveal their processes clearly enough to distinguish the different types of neuroglial cells. Their characteristics and identification will be described later in this chapter.
Most of the image is occupied by pink-stained material containing numerous fine filaments. This material consists largely of neuronal and neuroglial cell processes. In routine histological preparations, these processes cannot usually be assigned to specific cell types or individual cells. The different types of neuroglial cells and their processes will be examined later in this chapter.
Nervous tissue has a high metabolic demand and requires a continuous supply of oxygen and nutrients. Consequently, it is highly vascularized. Numerous small spaces can be seen within the pink-stained tissue; these correspond to blood capillaries, some of which are highlighted in red.
