The endocrine system is comprised of glands that produce hormones which are chemicals released into the bloodstream to stimulate reactions in target organs. The hypothalamus regulates the pituitary gland which controls other endocrine glands. The pituitary gland produces hormones that regulate growth, metabolism, reproduction, lactation, and water balance. Other important glands are the thyroid, parathyroid, adrenal, pancreas, ovaries and testes which regulate processes like calcium levels, stress response, blood sugar, and sexual development.

2. Endocrine System
• Comprised of glands
and other tissues that
produce hormones

3. Endocrine System
• Hormones
– chemicals produced in
response to specific stimuli
that stimulate reactions in
specific body organs and
tissues
– released directly into the
bloodstream, interact with
receptors causing the
target tissue to perform a
specific function

4. Endocrine System
• Hypothalamus
– Regulates and
coordinates many
endocrine organs by
regulating the release
of hormones from the
pituitary gland
– Regulates body
temperature, appetite,
and thirst

5. Hormones of the Hypothalmus
• Anti-diuretic hormone (ADH): increases water
absorption into the blood by the kidneys
• Corticotropin-releasing hormone (CRH): triggers the
release of corticosteroids, which help regulate
metabolism and immune response
• Gonadotropin-releasing hormone (GnRH): stimulates
the release of follicle stimulating hormone (FSH) and
luteinizing hormone (LH), which work together to ensure
normal functioning of the ovaries and testes

6. Hormones of the Hypothalmus
• Growth hormone-releasing hormone (GHRH) or growth hormone-
inhibiting hormone (GHIH): triggers the release of growth hormone (GH);
GHIH has the opposite effect . GH is essential to maintaining a healthy body
composition (bone, muscle growth)
• Oxytocin: aids with: ability to trust, body temperature, sleep cycles, and
lactation
• Prolactin-releasing hormone (PRH) or prolactin-inhibiting hormone
(PIH): prompts the production of prolactin for milk production. PIH inhibits
prolactin
• Thyrotropin releasing hormone (TRH): triggers the release of thyroid
stimulating hormone (TSH), which stimulates release of thyroid hormones -
regulate metabolism, energy, and growth and development

7. Endocrine System
• Pituitary
– Anterior pituitary
– Posterior pituitary
• Important roles in
regulating growth,
metabolism,
reproduction, lactation,
and water balance

8. Hormones of the Anterior Pituitary
• Adrenocorticotropic hormone (ACTH): ACTH stimulates the adrenal
glands to produce hormones
• Follicle-stimulating hormone (FSH): FSH works with LH to ensure normal
functioning of the ovaries and testes
• Growth hormone (GH): GH is essential in early years to maintaining a
healthy body composition and for growth in children. In adults, it aids
healthy bone and muscle mass and affects fat distribution
• Luteinizing hormone (LH): LH works with FSH to ensure normal
functioning of the ovaries and testes
• Prolactin: Prolactin stimulates breast milk production
• Thyroid-stimulating hormone (TSH): TSH stimulates the thyroid gland to
produce hormones.

9. Hormones of the Posterior Pituitary
• Anti-diuretic hormone (ADH): prompts
the kidneys to increase water absorption in
the blood
• Oxytocin: contracting the uterus during
childbirth, milk production, trust

10. Endocrine System
• Thyroid gland
– Thyroxine
• Regulates metabolism,
and calcitonin
– Calcitonin lowers
blood calcium levels
when high by
inhibiting osetoclasts
• Parathyroid gland
– Parathyroid hormone
• Raises blood calcium
levels when low by
stimulating osteoclasts

11. Endocrine System
• Adrenal glands
– Located on top of
kidneys
– Adrenal cortex
produces cortisol and
sex hormones
– The adrenal medulla
produces epinephrine
and norepinephrine

12. Endocrine System
• Pancreas
– Produce bicarbonate
(buffer) and digestive
enzymes
– Insulin
• Keeps glucose
concentrations from
getting too high
– Glucagon
• Triggers release of
glucose when
concentrations are low

13. Endocrine System
• Ovaries
– Produce estrogens, progesterone
– Prepare the reproductive tract for pregnancy
and are also responsible for female sexual
behavior and mammary gland development
• Testes
– Produce testosterone and estrogens
– Involved in sperm production and maturation
as well as the secondary sex characteristics
of males