Pituitary gland:
a small organ--about the
size of a dime and
located in the center of
the brain--which makes
hormones that affect
growth and the functions
of other glands in the
body. 1
Introduction: The
pituitary is a small
gland inside the head,
behind the bridge of the
nose. Though small, it
produces many important
hormones that regulate
basic body functions.
The major pituitary
hormones and their
effects are:
-
prolactin--controls
formation of breast
milk, influences
fertility, and
influences bone
strength;
-
growth
hormone--regulates
body growth,
especially during
adolescence;
-
adrenocorticotropin
(ACTH)--stimulates
the adrenal glands
to produce cortisol;
-
thyrotropin
(TSH)--stimulates
the thyroid gland to
produce thyroid
hormones;
-
luteinizing hormone
(LH)--stimulates the
ovaries or testes to
produce sex hormones
that determine many
features of
"maleness" or
"femaleness"; and
-
follicle stimulating
hormone
(FSH)--regulates
fertility in men
through sperm
production and in
women through
ovulation.
2
The pituitary gland,
sometimes called the
master gland, plays a
critical role in
regulating growth and
development, metabolism,
and reproduction. It
produces prolactin and a
variety of other key
hormones. These include
growth hormone, which
regulates growth; ACTH
(corticotropin), which
stimulates the adrenal
glands to produce
cortisol; thyrotropin,
which signals the
thyroid gland to produce
thyroid hormone; and
luteinizing hormone and
follicle-stimulating
hormone, which regulate
ovulation and estrogen
and progesterone
production in women, and
sperm formation and
testosterone production
in men.
The pituitary gland sits
in the middle of the
head in a bony box
called the sella
turcica. The eye
nerves sit directly
above the pituitary
gland. Enlargement of
the gland can cause
local symptoms such as
headaches or visual
disturbances. Pituitary
tumors may also impair
production of one or
more pituitary hormones,
causing reduced
pituitary function
(hypopituitarism).
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