Endocrine Packet 1

types of glands

sebaceous gland (sweat)

mammary glands (lactate)

organs that secrete hormones

endocrine system

a network of glands that produce the hormones used for communication between cells

gland

an organ that produces a hormone

endocrine gland

releases a hormone into the blood

hormone

chemical messengers that travel through the blood to their target organ or cell

what do hormones target

some hormones target only one organ and others target multiple cells in the body

what do hormones control

mood, growth, development, organs, metabolism, and reproduction

what system do glands work based on

negative feedback

• gland A detects low levels of hormone B

• gland A releases hormone A

• hormone A stimulates gland B to produce hormone B

• when hormone B levels return to normal, gland A stops making hormone A

components of the endocrine system

• pituitary, pineal, and hypothalamus in the brain

• thyroid and parathyroid in the throat

• thymus between the lungs

• adrenal on top of the kidneys

• pancreas behind the stomach

• ovaries and testes in the pelvic region

hypothalamus

• connection between the nervous system and endocrine system

• tells the pituitary gland when to start and stop releasing hormones

what is the endocrine system’s master gland

the pituitary gland

pituitary gland

• takes info from the brain and tells other organs what to do

• divided into anterior and posterior lobes

anterior pituitary gland hormones

• follicle stimulating hormone

• luteinizing hormone

• adrenocorticotropic hormone

• thyroid stimulating hormone

• prolactin

• growth hormone

follicle stimulating hormone

stimulates the development of the ova and sperm

luteinizing hormone

the production of estrogen and testosterone

adrenocorticotropic hormone

stimulates the adrenal glands to produce other hormones

thyroid stimulating hormone

stimulates the thyroid gland to produce T3 and T4 (thyroid hormone)

prolactin

produces lactate in breast feeding mothers

growth hormone

promotes cell division in cartilage and bones

posterior pituitary gland hormones

oxytocin and antidiuretic hormone (vasopressin)

oxytocin

helps with milk ejection during breast feeding

antidiuretic hormone (vasopressin)

regulates blood pressure and water balance in the body using the kidneys

pineal gland

produces melatonin to help you prepare for sleep

thyroid gland

produces T3 and T4 which regulates growth and metabolism

hyperthyroidism

too much thyroid hormone - everything happens faster

ex: high heart rate, diarrhea, weight loss

hypothyroidism

too little thyroid hormone - everything happens more slowly

ex: slow heart rate, constipation, weight gain

what else does the thyroid produce

calcitonin which helps maintain bone strength by incorporating calcium into the bones

what part of the thyroid produces calcitonin

the C cells

parathyroid glands

• 4 small glands located on the posterior side of the thyroid

• help with bone health by regulating calcium and phosphorus levels through PTH

• named for their location - they have nothing to do with thyroid hormone

thymus

• produces white blood cells called T lymphocytes which help fight infection while children’s immune systems are developing

• atrophies over time

layers of the adrenal glands

adrenal cortex - outside

adrenal medulla - inside

adrenal medulla

produces the “fight or flight” hormone - adrenaline (epinephrine)

adrenal cortex

produces hormones that regulate electrolytes, blood sugar, and sexual function (salt sugar and sex)

pancreas

• part of the digestive and endocrine systems

• produces insulin and glucagon which are used for regulating glucose levels in the blood and cells

ovaries

• produce estrogen and progesterone

• develop breasts at puberty, regulate menstruation, and support pregnancy

testes

• produce testosterone in men

• allow growth or facial and body hair, penis growth, and sperm production

if you have an endocrine disorder you may have problems with

• development during pregnancy

• becoming pregnant

• managing stress

• weight gain

• weak bones

• lack of energy

acromegaly

• a person continues producing too much growth hormone after growth has stopped and bones get larger

• usually affects the hands, feet, and face

• happens in middle age

adrenal insufficiency

• lack of the stress hormone cortisol

what is a common cause of adrenal insufficiency

addison’s disease - autoimmune disease that destroys the ability of the adrenal cortex to produce cortisol

what is a complication of untreated adrenal insufficiency

adrenal crisis due to electrolyte imbalance which may be fatal

amenorrhea

• lack of a period for three menstruation cycles or more

• associated with low levels of estrogen

natural causes for amenorrhea

• pregnancy

• menopause

abnormal causes of amenorrhea

• excessive exercise

• low body fat

• PMOS

• surgery

• thyroid disorders

cushing syndrome

• too much cortisol in the body

• caused by excessive steroid use or overproduction of cortisol

symptoms of cushing syndrome

• weight gain

• stretch marks

• bruising easily

• weakened muscles / bones

• hump on their upper back

hyperthyroidism

• thyroid is producing too much thyroid hormone - everything happens faster

• high heart rate, weight loss, diarrhea, trouble sleeping, nervous feeling

hypogonadism

• testes / ovaries produce little or no sex hormones

• low testosterone in men

• low estrogen in women

hypothyroidism

• thyroid gland produces low levels of thyroid hormone - everything slows down

• slow heart rate, weight gain, constipation, tired, muscle and joint pains

hypopituitarism

• low levels or hormones that are secreted by the pituitary gland

• glands controlled by the pituitary do not receive their messages

causes of hypopituitarism

damage or tumor on the pituitary

multiple endocrine neoplasia

• genetic disorders that cause tumors on two or more endocrine glands

• may be inherited from parents or arise sporadically

• tumore produce increased amounts of their hormones based on the organ they involve

osteoporosis

• the hormones needed for healthy bone are at low levels

• testosterone is low in men, estrogen is low in women

• the rate of new bone growth does not equal the rate of bone loss

• may be caused by increased parathyroid hormone

• decreased bone density over time leads to hip and spine fractures

polyendocrine metabolic ovarian syndrome (PCOS formerly)

• an imbalance of reproductive hormones that causes no egg production or the egg to not drop during ovulation

• usually due to high androgen (testosterone) levels in women

• causes acne, growth of hair on the face/chin, and irregular periods

precocious puberty

• when puberty happens at a very young age - younger than 8 for girls, and 9 for boys

• due to inappropriate production of gonadotropin releasing hormone from the hypothalamus (central)

• ovarian cyst can cause elevated estrogen (peripheral)

• testicular tumor can cause elevated testosterone (peripheral)

premature ovarian failure

• when estrogen declines before age 40 from reduced production by the ovaries

causes of premature ovarian failure

genetic disorders, surgery, or chemotherapy

when is a decline in estrogen considered normal

after age 40 along with menopause

what factors affect the endocrine system

• stress, infections, chemical exposure

• genes and lifestyle factors can increase risk for endocrine disorders