Destruction of anterior horn cells related to
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Answer:
Anterior horn cells (α-motor neurons), located in the anterior gray matter of the spinal cord, are found at every segment and are concentrated in the cervical and lumbosacral enlargements. Morphologic differentiation of the anterior horn cells is most evident from 12 to 14 weeks' gestation. There is a period of normal differentiation, followed by programmed cell death. Anterior horn cells are clustered into medial and lateral cell divisions (Figure 140-1). The medial group is subdivided into ventromedial and dorsomedial components. The ventromedial component innervates the superficial larger muscles, and the dorsomedial component innervates the small, deep muscles adjacent to the spine. The lateral cell mass is also subdivided into groups. The ventrolateral group innervates extensor muscles, and the centrodorsal group innervates flexor muscles. These groups of neurons are located in a relatively small region; therefore deleterious influences harm cells from more than one group and weakness may be widespread.
Motor neurons in the nuclei of brainstem cranial nerves are homologous to spinal cord anterior horn cells. Therefore pathologic mechanisms that compromise the cranial motor neurons may initiate symptoms and signs that mimic anterior horn cell dysfunction in the spinal cord. Muscular atrophy, severe weakness, and fasciculations without sensory deficit are signs of anterior horn cell disease. When sensory function is impaired in conjunction with anterior horn cell disease, dysfunction of adjacent tracts of the spinal cord or the peripheral nerves may be present.
Answer:
Motor neurons in the nuclei of the brainstem cranial nerves are homologous to the spinal cord anterior horn cells. The destruction of the anterior horn cells of the spinal cord would result in the loss of voluntary motor impulses because it is majorly related to the motor impulses.