endocrine system

anterior pituitary (adenohypophysis)

make and release its own hormones: GH, TSH, ACTH, LH, FSH, PROLACTIN

gonadotropin-releasing hormone (GnRH)

made by hypothalamus; travels to AP & tells pituitary to release LH & FSH; signals pituitary to to release/inhibit hormones

growth hormone (GH)

stimulates elongation of bone and cartilage in children before growth plates close; stimulates cell reproduction & cell regeneration

thyroid-stimualting hormone (TSH)

tells thyroid gland how much thyroid hormone to make; hypothyroidism (↓ TH ↑TSH) + hyperthyroidism (↑ TH ↓ TSH)

adrenocorticotropic hormone (ACTH)

tells adrenal glands to make cortisol l

luteinizing hormone (LH)

W: triggers ovulation, manage monthly cycles, helps form corpus luteum with makes progesterone for early pregnancy

M: tells leydig cells to make testosterone, aids in making healthy sperm cells

follicle-stimulating hormone

W: stimulates growth of ovarian follicles

M: helps testicles make sperm

prolactin

stimulate milk production

posterior pituitary (neurohypophysis)

stores & releases hormones made by hypothalamus: oxytocin & antidiuretic hormone (ADH)

oxytocin

triggers muscle contractions during childbirth and milk flow during breastfeeding

antidiuretic hormone (ADH)

tells your kidneys to hold onto water, which controls how much urine you make and keeps your blood fluid levels and blood pressure balanced

hypothalamus

link between nervous & endocrine systems

adrenal medulla

inner core of adrenal gland that secretes epinephrine (adrenaline) + norepinephrine (noradrenaline) to control FOF

adrenaline (epi)

“fight or flight”; ↑ HR, boost BP, expand airways, redirecting blood flow, ↑ sugar

noradrenaline (norepi)

constrict blood vessels & redirect blood where needed

adrenal cortex

outermost layer of adrenal gland which produce hormones that help regulate metabolism & immune response

zone reticularis (innermost)

secretes androgens (male sex hormone) like DHEA (precursor for estrogen & testosterone)

zona fasciculata (middle)

secrete glucocorticoids (cortisol)=manage metabolism & response to stress

zone glomerulosa (outer)

secrete mineralocorticoids (aldosterone)=control BP & balance salt/water

thyroid gland

regulates body’s metabolic rate and energy production

positive feedback

feedback mechanism that amplifies the effects of a system

pineal gland

secretes melatonin, regulates circadian rhythm & control sleep-wake cycles

pancreas

exocrine and endocrine functions

endocrine function

clusters of cells called pancreatic islets that produce hormones like insulin (lowers blood sugar) and glucagon (raises blood sugar) directly into the bloodstream (ductless)

exocrine function

s; lipase for fats, amylase for carbohydrates, and proteases for proteins which travel through ducts (sweat, salivary, mammary) into the small intestine to break down food

thyroxine (T4)

secreted by thyroid gland regulating metabolism, HR & growth

parathyroid gland

raise calcium levels by releasing parathyroid hormone

calcitonin (thyroid)

lower calcium levels

aldosterone

made in adrenal glands; tells kidney to keep sodium and water while getting rid of potassium

infundibulum

connects hypothalamus to AP and responsible for transport of hormones

dwarfism

↓ GH, short stature with normal proportions

acromegaly

↑ GH, large hands/feet, protruding jaw

addison’s disease

↓ cortisol & aldosterone; ↓ weight & BP, fatigue

cushing’s disease

↑ cortisol; ↑ weight & blood sugar

diencephalon

consist of thalamus, hypothalamus, pineal gland

thymosin

aids in maturation of T-lymphocytes, essential for immune response

cortisol

increase blood sugar levels, reduce inflammation

isthmus

connects two lobes of thyroid gland