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During the last decade research on neural transplantation in
mammals has grown extensively, and has attracted the attention of
many young inquisitive scientists. This growth, as the critics
point out, has been somewhat random, and has resulted neither in
the formulation of basic concepts nor in any other significant
achievement. For instance, they question-how is it possible to jump
into functional research with clinical bearing when the basic
morphological work has not yet been conducted? The criticism,
objectively speaking, is valid and is supported by the fact that
every investigator who has stepped into this unex plored field of
neurosciences has formulated questions in his own way, has followed
his own "model" oftransplantation, and has arrived at his own
unique conclusions. The potential danger, as the critics emphasize,
in this type of approach lies in that instead of evolving into a
scientifically solid and valuable field of research, it may end in
a confusing and conflicting mass of questionable claims and
subjective opinions. The present situation, very likely, is a
reflection of unrestrained enthusiasm and imaginativeness of the
investigators, and the demands of the times for the so-called
"newsworthy" and "breakthrough" publications. Despite these
limitations, two important facts have been estab lished in this
field. First, as far as transplantation of neural tissues per se is
concerned, what was considered impossible by some critics about
10-12 years ago has been shown to be possible."
The presence of nerve cells in the white matter of the spinal cord
and in the spinal and cranial nerves has attracted the attention of
some researchers in the past. Because of their location in such
unexpected regions, these neurons provided a rich field of
speculation regarding their nature and function. This was partic
ularly true about the nerve cells lying in the spinal white matter.
From phylogenetic considerations, neurons in the spinal white
matter are present more abundantly in amphibians, reptiles and
brids than in mammals. A. brief survey of literature on lower
vertebrates indicates that GASKELL (1885, 1889) was the first to
describe the displaced neurons in the white matter of the spinal
cord of alligators and various species of birds. In his
consideration they were displaced ganglion cells. In 1902 von
KOELLIKER gave an exhaustive account of such neurons in the white
matter of the spinal cord of reptiles and birds. In these animals
he observed clusters of such neurons running in longitudinal
columns and thus was able to group them into nuclei known as
"Hofmann's nuclei." Further, he suggested that these nuclei arise
from the mass of the ventral horn and that they may give rise t. o
preganglionic fibers, motor fibers or ventral commissural fibers.
In t. he ensuing years investigation of these nuclei was extended
by STREE TER, KRAUSE, TERNI, HUBER and others (quoted from ARIENS
KAPPERS et. aI., 1960, Vol. I, p. 206-210)."
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