Endocrine System Flashcards
What controls the pituitary gland?
What does it release in order to control it?
- hypothalamus
- releasing and inhibiting hormones.
What is the function of the endocrine system?
has a set of organs that secrete/ produce hormones, aka chemical messengers, into the circulatory system, which transports the hormones to go and affect target organs.
neurotransmitters from nervous system are also chemical messengers
Endocrine hormones are released into the [_____]
blood stream
Exocrine products are sent through [____] to [___]
- ducts
- skin or mucus membrane
products include: sweat, tears, enzymes-ie. digestive enzymes, mucus
____ type of hormones bind to cell membrane receptors on surface of target organs
- amino acids based [polar]
___ type of hormones binds to intracellular receptors
* list examples of these types of hormones
- steroid [non-polar] ie. estrogene, progesterone, testosterone, cortisol, aldoesterone, thyroxine
What hormones are released by the Hypothalamus? (look at image on ipad)
- TRH (thyrotrpoin releasing hormone) –> stimulate TSH release from anterior pituitary
- Dopamine (and estrogen and progesterone released from ovaries)–> inhibit prolactin release from anterior pituitary
- CRH –> stimulate ACTH release from anterior pituitary
- GHRH (GROWTH HORMONE RELEASING HORMONE) –> stimulate GH release from anterior pituitary
- somatostatin –> inhibit GH release from anteiror pituitary
- GnRH (GONADotropin releasing hormone)–> stimulate FSH and LH release from anterior pituitary
- What hormones does the anterior pituitary gland release?
- Where is this structure located?
- What is the general function of these hormones?
- ACTH, TSH, FSH, LH, PRL, GH, MSH (melanocyte stimulating hormone)
- base of the brain
- controls growth and development
ACTH
What secretes this?
stimulates adrenal cortex to secrete corticosteroids (steroid hormones of adrenal cortex) aka glucocorticoids
TSH
What secretes this?
stimulates the thyroid gland to release thyroid hormone (T3 and T4)
FSH
What secretes this?
Gamete production
* Female: stimulates production/development of ova aka eggs (oogenesis) as well as follicle maturation
* Male: spermatogenesis
LH
What secretes this?
Sex hormone production
* females ovaries: estrogen and progesterone; surge triggers ovulation
* males testis: testosterone
Prolactin (PRL)
stimulates milk production in the mammary gland
inhibited by dopamine release from hypothalamus and also estrogen and progesterone release during pregnancy
Growth hormone
stimulates growth (long bones that are still growing @ epiphyseal plate and muscles) and metabolic functions and cell repair
almost all cells have receptors for this
MSH
What secretes this?
causes melaoncytes to make pigement on the skin, hair, and iris
- What hormones does the posterior pituitary gland release?
- Where is this structure located?
- Special note about these posterior pituitary gland hormones?
- ADH/ vasopression and oxytocin
- behind the anterior pituitary
- both these hormones are MADE in the PVN of hypothalamus but are RELEASED in the posterior pituitary
ADH
* what is the other name?
* when is this activated?
What secretes this?
- vasopressin
- causes late DCT and collecting tube to reabsorb water (water retention)–> increases blood volume (and so BP) or decreases dehydration and so less urine produced
- low bp, when sweating alot or high plasma osmolarity ie. high salts, electrolytes
pth
oxytocin
What secretes this?
stimulates
* uterus contraction to induce labor in child birth and after birth allows uterus to go back to normal size and to prevent excessive post-partum blood loss.
* contraction of smooth muscle around mammary glands to stimulate lactation- milk let down- when the child stimulates the nipples
* stimulates brain to allow emotional bonding (ie. after orgasm or mother and child)
secreted by posterior pituitary BUT made in the hypothalamus
- What hormone does the pineal gland secrete?
- Where is the pineal gland located?
- melatonin
- CENTER of the brain B/W THE 2 HEMISPHERES (epithalamus)
Melatonin
What secretes this?
regulates sleep cycles (makes you sleepy); biorhythms
pineal gland (epithalamus) at the center of the brain b/w the 2 hemispheres when it is dark
- What hormones does the thyroid gland release?
- Where is this structure located?
- What is the general function of these hormones?
What stimulates the thyroid gland to release hormones?
- T3, T4, calcitonin
- neck
- regulation of growth, development, and metabolism
TSH
T3
What secretes this?
metabolism, causes cells to use more energy (increases ATP production)
T4
What secretes this?
metabolism and temperature; causes cells to use more energy (increases ATP production)
Calcitonin
What secretes this?
inhibits the release of Ca from bones and stimulates the storage of Ca in bone –> decreases blood Ca
- What is hormone is secreted by the parathyroid gland?
- What cells in parathyroid gland secrete this?
- Where is it located?
- PTH
- chief cells
- 4 glands on the thyroid
PTH
What secretes this?
stimulates
* bone breakdown and release of Ca from bones into the blood from indirect activation of osteoclasts bc PTH binds to osteoblasts only, which then through cell to cell contact activate osteoclast precursor cells into osteoclasts
* Ca reabsorption from kidneys DCT (direct and indirect) and Ca absorption from small intestines (indirect) through PTH aid (BUT NOT REQUIRED) in activation of Vit D in the kidney’s, so Ca can be used to later build bone or be used in other parts of the body bc Ca is needed for cell communication in neurons and in muscle contractions.
* all to increase blood Ca
direct= PTH direct cause; indirect= thru PTH Vit D activation
What hormones are secreted by the thymus?
thymosin
the thymus involutes with age