Download Hormones from Endocrine Glands

Topic 21
Please refer to textbook and notes for this topic. Disorders/diseases (hypo- and hyper-secretions may be
listed below).
There are also many helpful websites like:
http://quizlet.com/10761323/endocrine-system-hormone-list-flash-cards/
Diagram One: Get a general idea of where the pituitary and hypothalamus are situated in humans.
Don’t worry about memorizing any other terms on this diagram for this topic
Do not label this diagram there is too much info here to label. But look at how the hypothalamus and
pituitary gland communicate.
Hormones from Endocrine Glands
Hypothalamus (these are releasing factors/hormones)
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Thyrotropin-releasing hormone (TRH)
o Stimulates secretion of TSH and prolactin.
Corticotropin-releasing hormone (CRH)
o Triggers the release of ACTH.
Growth hormone-releasing hormone (GHRH)
o Triggers the release of growth hormone.
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Growth hormone inhibitory hormone (GHIH) (somatostatin)
o Inhibits growth hormone secretion.
Gonadotropin-releasing hormone (GnRH)
o Triggers the release of LH and FSH.
Dopamine or prolactin-inhibiting factor (PIF)
o Inhibits prolactin secretion.
Pituitary Gland
The pituitary can be divided into the anterior and posterior gland. The hormones below are
secreted by the anterior pituitary gland, except for ADH and oxytocin, which is secreted by the
posterior pituitary gland. The hypothalamus controls the release of anterior pituitary hormones
by way of releasing factors (see above). All are anterior lobe hormones unless specified.
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Adrenocorticotropic hormone (ACTH)
o Stimulates the synthesis and secretion of adrenocortical hormones (cortisol, androgens,
and aldosterone).
Antidiuretic hormone (ADH) / Vasopressin (posterior lobe)
o Stimulates the reabsorption of water from urine in the kidneys.
o It also triggers vasoconstriction.
o Both the retention of water and vasoconstriction increases blood pressure.
Follicle-stimulating hormone (FSH)
o In women, it stimulates the growth of the ovarian follicle.
o In men, it stimulates the maturation of sperm in the testes.
Growth hormone
o Stimulates the synthesis of proteins and growth of cells and tissues.
Luteinizing hormone (LH)
o In women, it stimulates ovulation, formation of the corpus luteum and production of
estrogen and progesterone.
o In men, it stimulates the testes to produce testosterone.
Oxytocin (posterior lobe)
o Stimulates the secretion of milk from the breasts.
o Triggers and enhances of uterine contractions.
Prolactin
o Promotes the development of breasts in women and milk production and secretion.
Thyroid-stimulating hormone (TSH)
o Stimulates the synthesis and secretion of thyroid hormones (thyroxine and
triiodothyronine).
Pineal Gland
The pineal gland was believed to play no significant role in the body and was thought of as a
vestigial organ. It is now known that the pineal gland secretes melatonin and related hormones
which may play a role in sleep and possibly affect the secretion of luteinizing hormone and
follicle-stimulating hormone.
Thyroid
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Thyroxine (T4) and Triiodothyronine (T3)
o Increases the body’s metabolic rate by acting on most cells.
o Made with iodine
Calcitonin
o Promotes calcium deposition in the bones.
o Also reduces the calcium levels present in the blood and tissue fluid.
Parathyroid
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Parathyroid hormone (PTH or Parathormone)
o Increases calcium absorption from the gastrointestinal tract.
o Triggers the release of calcium from the bones.
o These two effects increase the calcium concentration in the blood.
Adrenal cortex
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Cortisol:
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It is a glucocorticoid that has a wide range of metabolic and anti-inflammatory effects
Aldosterone
o It is a mineralocorticoid that regulates the concentration of essential electrolytes in the
body. It is more sensitive to [Na] than ACTH.
Adrenal medulla
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Norepinephrine and epinephrine
o Has the same effects on target organs as stimulation by the sympathetic nerves but is
longer lasting.
Pancreas
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Insulin
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Acts on cells to increase glucose uptake from the blood.
Glucagon
o Promotes the release of stored glucose from the liver and production of glucose if
necessary.
Testes
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Testosterone
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Promotes the development and maturation of the testes, as well as the sexual
characteristics of men.
Ovaries
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Estrogen
o Promotes tissue development in the female reproductive system, including the ovaries,
Fallopian tubes (oviducts), uterus and genitalia.
o Sustains the development of the corpus luteum, as well as the sexual characteristics of
women.
Progesterone
o Promotes secretory changes in the uterus and fallopian tubes in preparation of
pregnancy.
o Stimulates the development of milk-producing tissue in the breast but does not
stimulate actual breast milk secretion.
Thymus Gland
The thymus gland in adults seems to have little functionality compared to early life but plays a
role in the maturation of immune cells (especially T-cells). It is not an endocrine gland.
Thymosin is the hormone made here.
See Teacher for details of glands other than endocrine (it may not be included in test #21)
The following tissues and organs in the body also produce and secrete hormones but are not
endocrine glands. Important SAT hormones *
Adipocytes (Fat Cells)
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Leptin
Heart
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Atrial natriuretic peptide (ANP)
Kidney
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Renin*
1,25-Dihydroxycholecalciferol
Erythropoietin
Placenta
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Human chorionic gonadotropin (HCG)*
Human somatomammotropin
Estrogen*
Progesterone*
Stomach
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Gastrin*
Ghrelin
Discussed under Digestive Hormones Topic
Small intestine
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Secretin*
Cholecystokinin (CCK)*
SOME DISORDERS OF THE ENDOCRINE SYSTEM
*important ones for SAT
1. DIABETES MELLITUS: *
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pancreas does not secrete enough insulin  cells cannot absorb glucose  low energy levels,
sugar in urine, more urine, thirst
1. DIABETES INSIPIDUS: *
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posterior pituitary does not make enough ADH or its effects are blocked, ADH helps absorb
water in the kidneys  low ADH  causes large volumes of urine
2. HYPERTHYROIDISM (GRAVES DISEASE): *
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hypersecretion of thyroxine by the thyroid gland, thyroid may be malfunctioning or too much
TSH from pituitary,  increased metabolic rate, inc. heart rate, weight loss, sweating, high B.P.,
eyeballs protrude, person may always feel hot
3. HYPOTHYROIDISM (GOITER): *
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an iodine deficiency causes less thyroxine to be released by the thyroid gland thus causing low
metabolic rate, weight gain, cold, slow pulse, puffy, also  low thyroxine  breaks the negative
feedback loop thus the pituitary keeps releasing TSH  causing the thyroid to swell up
4. HYPOTHYROIDISM (CRETINISM): in babies
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normal thyroxine levels at birth via the mother through the placenta
low thyroxine after birth  abnormal bone development, mental retardation, low body temp.,
lethargy, stunted growth
5. HYPOTHYROIDISM (MYXEDEMA): in adults
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low thyroxine  low metabolic rate, lethargy, weight gain, edema, hair loss
6. DWARFISM: *
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the anterior pituitary does not release enough growth hormone  reduced muscle and bone
growth, stunted
7. GIGANTISM/GIANTISM: *
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the anterior pituitary releases too much growth hormone  bones and muscles grow to
abnormally large sizes
8. SADS (Seasonal Affective Disorder):
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pineal gland behind the eye releases too much melatonin  cells prepare for winter, sleepy,
sad, tired, gain weight, depressed
9. ACROMEGALY: *
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anterior pituitary releases too much growth hormone after the growth plates have fused
together, bones can no longer grow in length but instead widen & thicken
Below is extra information used in class to discuss the physiology of the endocrine system: