Page 344 - Atlas of Histology with Functional Correlations

FIGURE 9.5 ■ Spinal cord: midcervical region (transverse section). Stain: silver
impregnation (Cajal method). Low magnification.

FIGURE 9.6 | Spinal Cord: Anterior Gray Horn,

Motor Neurons, and Adjacent Anterior White

Matter

A section of the white matter and the gray matter of the anterior horn of the
spinal cord is illustrated at a higher magnification. The gray matter contains

large, multipolar motor neurons (2, 3). These are characterized by numerous
dendrites (5, 6) that extend in different directions from the perikaryon (cell
bodies). In some neurons, the nucleus (8) is visible with its prominent nucleolus
(8). In other neurons, the plane of section missed the nucleus and the perikaryon

appears empty (2). Surrounding the motor neurons are the small, light-staining,
supportive cells, the neuroglia (7).

The white matter contains closely packed myelinated axons. In cross
sections, the axons (1) appear dark-stained and surrounded by clear spaces that
are the remnants of the lost myelin sheaths. The axons in the white matter

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