Tensas gazette., 1915-03-05
(Copyrisht. 1914. by A. S. Cray)
THE THYROID GLAND.


Before the appearance of any GEN.
trail nervous system in the lowest or
ganisms 1t is by chemical means, by
so called automatic excitation through
the action of products of decomposi-
tion by the organs in different parts
of the body, that any coordination OF
function is determined, either among
the different organs Of a colony or
among the various cells making up
a multicellular organism such as a
sponge.
The mechanism which determines
the movement of phagocytic cells-a
phagocyte is any cell possessing the
property of absorbing and digesting-
the chase of food, the escape from
noxious environment or the approach
OF sexual cells, has been given the
name of chemotaxis. The name sig
nifies the attraction or repulsion ex-
hibited by certain chemicals to living
cells. Since the application Of these
chemical stimuli depends on their diff
fusion through the medium bathing
the cells, the process very obviously
must necessarily be both slow and
lasting.
The most important and definite
knowledge concerning the actions OF
these internal chemical secretions has
perhaps resulted from work done on
the thyroid glands, those shieldlike
vesicular bodies filled with colloid ma
terial located on the sides OF the
trachea (windpipe) just below our
adams apple" (the thyroid carti-
lage). Carried by the blood to all
parts of the body, the metabolic pro-
ducts Of the thyroid gland affect every
other gland and tissue and may act
either to heighten or to reduce the
activity of other organs. according to
their specific function.
In 1856 Schiff showed that removal
of the thyroid in dogs is followed usu-
ally by the death Of the animals in
one to four weeks.
The disturbances appearing after
removal of the thyroid affect the most
widely different organic systems Of the
body. The skin, especially that Of the
head and face. becomes greatly swol-
len because of an accumulation Of
mucin In the subcutaneous connective
tissue. Subsequently the skin becomes
hard, rough and dry: its secretion
ceases; the hairs change and fall out;
the visible mucous membranes be-
come swollen and the voice becomes
harsh and monotonous. The internal
organs exhibit marked pathological
changes; the kidneys and the liver
undergo fatty and colloid degeneration
and the arterial walls take on a hya-
line (crystalline) degeneration. Meta
bolism is abnormally low; that is to
say. not only is the appetite poor. but
the ability to convert the food taken
into the body, to break down and re-
lease the energy therein contained. is
decreased.
Disturbances of the nervous and
muscular system following removal Of
the thyroid are profound: not infre-
quently functional disturbances such
as epilepsy ensue. All those parts Of
the brain which are active In the physi.
cal functions become functionally much
reduced. and In myxedematous cases
we meet with weak memory, extreme
irritability. stupidity and the like; all
Of which in turn find expression In a
marked decline of muscular tone and
In vigor Of the body movements sener-
ally.
In man any material disturbance in
the function of the thyroid produces
arrangement in the temperature and
heat regulating ability of the body;
the subnormal temperature is one of
the most constant symptoms and the
patient feels cold constantly.
In the growing organism liter sup
preston of the thyroid the ZONES fall
considerably behind in their develop
ment and the ossidcation of the carti.
lagos connecting bone processes is
materially delayed. The physical dis
turbances in the young are generally
more pronounced than in grown per-
sons.
Schiff and many others have found
that all these evil results of the COM
plete or partial destruction Of the thy.
roid In dogs might be obviated by
grating pieces of the thyroid into the
body. and this knowledge was quickly
applied with astonishing results to
human beings in cases of myxedema
and cretinism. Then. instead of graft.
ing thyroid tissues. 1t was found that
injection Of extracts under the skin,
or. better still. the simple feeding of
thyroid material. gave similarly favor
able results-the individuals recov.