Iowa state bystander. [volume] (Des Moines, Iowa) 1894-1916, 1915-02-19
Copyrisht. 1914. by A. S. Gray)
THE PARATHYRolD GLAND.

Copyrisht. 1914. "A. S. Gray)
THE PARATHYRolD GLAND.
We are compelled to use animal
such as the dog, the cat, the monke,
and the like for the purpose of secur
ing experimental confederation O
many theories because physiological
chemistry experiments along sucl
lines generally necessitate extensiv,
and dangerous surgical procedures
And although an abundance of expert
mental material is readily obtainable
the demonstrations OF theories enorm
ously important to man are necessar
lily slow, largely because of wide
spread prejudice against considering
conditions in the lower animals an
alogous to those found in the human.
SchiR noted fatal results to dogs
following removal of the thyroid in
1856 and wrote about it in 1859, but
no notice was taken of his work by
the surgical profession. Again in 1884
following reports OF the removal OF
human thyroids by Raverdin in 1882
and Kocher in 1888, Schiff wrote show.
ing that after complete extirpation
OF the thyroid all the animals died in
four to twenty.seven days. These ex-
periments were confirmed by various
observers, but in many instances the
symptoms shown by the animals sub.
sequent to the operation proved to be
OF most variable character, not only
In different species, but also in diff
ferent individuals of the same species.
A few Of the animals succumbed in a
few days. frequently with the accom-
paniment of commissions; others lived
for some months or even longer and
sank gradually from general lack of
nutrition, but occasionally dog would
survive the operation.
In the case of the human being
complete removal induced a like var
iety of symptoms, state resembling
myxedema and cretinism "a condition
of deficient development and idiocy).
besides anemia, a readiness to fatigue,
q sensation of cold and occasionally
tetany (convulsions).
The four insignificant pealike par
athyroid (near-thyroid) glands tucked
away behind the more prominent
thyroid gland for long time escaped
the eye of the anatomist, and for a
long time after they were discovered
they were given no particular consid.
GRAFTON. But careful investigation Of
these baby glands by anatomist, his.
tologist and embryologist proved them
to be Independent organs structurally
and functionally distinct from any
other tissues, and of vast importance
in the economy.
Experimental investigations demon
strated the parathyroids to be vital
organs of remarkable physiological
activity in wide range of animal
organisms. It was demonstrated that
rabbits deprived of these tiny bodies
died in commissions. Gradually the
significance of this observation dawned
upon surgeons and psychologists.
When the parathyroids alone are re-
moved the animal dies quickly with
acute symptoms, including convul-
sions; but when the thyroids alone
are removed the animal may survive
for long period, but will develop a
condition of chronic malnutrition sim
liar to the disease known 50 myxe.
dema in man. &.
The experimental evidence In the
case Of the parathyroids tends to sup
port the view that their function con-
sists OF in some way neutralizing toxic
substances formed elsewhere in the
body; they are poison destroying or
gans, whose principal function most
probably is to neutralize the metabol-
IL poisons particularly detrimental to
the nervous system. Therefore, after
removal Of these glands, death occurs
from the accumulation of the so-called
metabolic tetany poisons formed In
the blood and tissues, attacking the
nerves in the absence OF the normal
parathyroid secretions.
The tetany (convulsion) of pregnan-
cy and lactation, epilepsy, exophthalm-
ic goiter, paralysis agitans Shaking
palsy) and other conditions associated
with muscular tremor is closely identi-
fed with parathyroid insuff1ciency
And SO, too, is osteomalacia (morbid
ssoftening of bone), decaying teeth and
ricketts,. It is known that lack of lime
(calcium) in the organism leads to
tetany, hence calcium metabolism is
doubtless influenced by the parathy-
roid glands and the parathyroids In
- va course, gravely infiu-
enced Dy :. ( Of calcium. This Is a
fAct of vast Importance. as later IN.
ysstigations will prove.
Many observers have reported that