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The next anterior pituitary hormone that we'll discuss is adrenocorticotropic hormone or ACTH.
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This hormone is also called corticotropin because it is secreted by the corticotropic cells. The
precursor to corticotropin is pro-opiomelanocortin. ACH stimulates the adrenal cortex to
release corticosteroids such as cortisol and aldosterone. Regulation of ACTH release is triggered
by the hypothalamic corticotropin-releasing hormone in daily rhythms with the highest
levels of this hormone being released in the morning. Internal and external factors that alter
the release of this corticotropin-releasing hormone include things like fever, hypoglycemia
or low blood sugar, and stressors. For example, stress triggers the release of corticotropin-releasing
hormone which then leads to the production of cortisol which we sometimes refer to as a
stress hormone. The next anterior pituitary hormones that we'll discuss are the gonadotropins.
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These are follicle-stimulating hormone and luteinizing hormone. These are going to be secreted
by the gonadotropic cells of the anterior pituitary. Follicle-stimulating hormone is going to
be responsible for stimulating the production of gametes in the male with sperm and the female
with the ovum. Luteinizing hormone produces the production of gonadal hormones. In females,
luteinizing hormone helps a mature follicle of the ovum and triggers ovulation as well as the
release of estrogen and progesterone. In males, the luteinizing hormone stimulates the
production of testosterone. Luteinizing hormone and follicle-stimulating hormone are both
absent from the blood in prepubertal boys and girls, so before puberty. Regulation of
gonadotropin release is triggered by gonadotropin-releasing hormone during and after puberty
and is suppressed by gonadal hormones by way of negative feedback. The next anterior
pituitary hormone that we'll discuss is prolactin. Prolactin is going to be secreted by the
prolactin cells of the anterior pituitary. This directly stimulates milk production in females and
wow males do have prolactin. The role in males is not well understood. Regulation of prolactin
release is controlled by the prolactin-inhibiting hormone known as dopamine. Prolactin-inhibiting
hormone is going to prevent the release of prolactin until the prolactin is needed for lactation.
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With decreased levels of prolactin-inhibiting hormone, you get lactation after childbirth.
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Prolactin is also going to be stimulated by increased estrogen levels. This is the reason why
during the menstrual cycle breast swelling and tenderness occurs. Rising blood levels of
prolactin usually are going to happen toward the end of a pregnancy. Also, suckling is going to
stimulate prolactin release and promote continued milk production after childbirth.