Amanda Gil Period 3 Endocrine System
Major Functions
Homeostatic Mechanisms of Hormone Regulation
Steroid vs Non-steroid Hormones
Major Endocrine Glands/Organs
Diseases
diabetes inspidus: condition resulting from insufficient ADH
pituitary dwarfism: GH deficiency in childhood
gigantism: GH over secretion in childhood
acromegaly: GH over secretion in adulthood
hypothyroidism: under activity of thyroid gland, causes low metabolic rate, fatigue, weight gain in adults, causes cretinism in infants- poor bone growth
hyperthyroidism: overactivity in thyroid gland, causes high metabolic rate, restlessness, overeating, eye protusion, and can lead to the formation of a goiter
hypoparathyroidism: deficiency of PTH due to surgical removal or injury of to glands resulting in a decrease in blood calcium
hyperparathyroidism: excess of PTH, possibly due to parathyroid tumor and results in an increase in blood calcium
Addison disease: hyposecretion of glucorticods and mineralocorticods
Cushing syndrome: hypersecretion of adrenal cortisol hormones
diabetes mellitus: metabolic disease due to lack of insulin and inability of cells to recognize insulin
long term stress: lower resistance to infections/cancers, high BP, astherosclerosis, GI ulcers
causes disturbance in metabolism of carbohydrates, fats, and proteins
high blood glucose harms eyes, heart, kidneys, peripheral nerves
glucose entry into body cells is impaired
symptoms: hyperglycemia, glycosuria, polydipsia, polyphagia, acidosis
Type 1 diabetes mellitus: insulin dependent diabetes mellitus, autoimmune disorder where beta cells are destroyed so insulin production decreases/stops
Type 2 diabetes mellitus: noninsulin dependent diabetes mellitus, insulin is produced but not recognized
hypothalamus
anterior pituitary
posterior pituitary
pineal gland
parathyroid
thyroid
kidneys
pancreas
ovaries
adrenal cortex
stomach mucosa
intestinal mucosa
adipose tissue
adrenal glands
testes
adrenal medulla
gonads
placenta
T3 and T4 hormones control metabolic rate and growth and development ---->most tissues
GnRH hormone is associated with the production and secretion of LH/FSH in the pituitary gland ---> pituitary gland
secretin hormone deals with digestive secretions --->liver, pancreas, stomach
corticosteroid hormone controls key functions in the body, acts as anti-inflammatory, maintains blood sugar levels, BP strength, and regulates salt/water---> liver, adipose, brain, lung
thymus
epinephrine and norepinephrine increases metabolism and heart rate as a response to stress and excersize---> all tissues
thymosins provide immune response ---> t lymphocytes
Leptin hormone controls appetite, secretion proportional to fat stores---> Brain
GH deals with growth and development to all body tissues
LH stimulates ovulation and estrogen/testosterone secretion---> ovaries, testes(leydig cells)
renin regulates BP and aldosterone secretion---> smooth muscles in blood vessels and adrenal cortex
cortisol deals with metabolism and its response to stress and excersize--->all tissues
ACTH stimulates cortisol secretion and controls production of sex hormones and gametes ---> and renal cortex
inhibit inhibits synthesis and release of FSH/LH ---> pituitary gland and hypothalamus
FSH stimulates ovarian follicle growth, estrogen secretion, and sperm/egg production --->ovaries/testes
progesterone maintains pregnancy--->corpus luteum
melatonin stimulates circadian rhythm reproduction---> various tissues
TSH stimulates the production and secretion of thyroid hormones--->thyroid gland
PRL stimulates milk production and lactation --->mammary gland
dopamine creates feeling pleasure, satisfaction and motivation--->adrenal glands, kidneys
oxycotin stimulates contraction of uterus and milk ducts ---> uterine smooth muscles and mammary glands
EPO stimulates blood cell production --->bone marrow
aldosterone regulates salt, water balance and BP ---> primarily kidneys
gastrin promotes acid secretion --->stomach and intestines
calcitonin lowers blood calcium and phosphate---> bone
ADH stimulates water secretion and blood pressure ---> kidney, tubules, arteriole smooth muscles
insulin lowers blood sugar levels and stimulates metabolism of glucose ---> most body tissues but mostly muscles and liver
estrogen promotes development of secondary femal sex characteristics and menstrual cycle ---> reproductive organs
glucagon: elevates blood glucose levels ---> primarily liver
progesterone stimulates the lining of the uterus and prepares breasts for milk production ---> uterus
PTH elevates blood calcium---> bones, kidneys, small intestines
testosterone stimulates male sexual characteristics and maturation---> reproductive organs
negative feedback
positive feedback
steroid: derived from cholesterol
non steroid: produced from amino acids- amines, peptides, proteins, glycoproteins
works with the nervous system to maintain homeostasis
cells, tissues, organs called endocrine glands
endocrine glands secrete hormones into body fluids
hormones diffuse into bloodstream to act on specific target cells some distance away
precise in their actions on specific target cells
communicate with cells using hormones
endocrine glands and their hormones regulate metabolic processes within cells and the body
hormones: estrogen, testosterone, aldosterone, cortisol
hormones: norepinephrine, epinephrine, thyroid, antidiuretic, oxycotin, thyrotropin- releasing hormone, parathyroid, growth, prolactin, FSH, LH, thyroid stimulating
lipid soluble, can pass through cell membranes
carried in bloodstream weakly bound to plasma proteins
protein receptor located inside cell
hormone receptor complex binds with DNA and activates specific genes that direct the synthesis of specific proteins
the new protein can function as an enzyme that transports protein/hormone receptor then carries out the effects of a steroid hormone
combine with receptors in target cell membranes that have a binding and activity site
first messenger hormones
second messenger: chemicals in cell that respond to binding of a hormone and causes changes in a cell
signal transduction is the cascade of biological activity through the cell membrane to the inside, starting with the binding of a hormone
other proteins are activated as they carry out effects of the hormone
release of hormones from hypothalamus controls secretions of interior pituitary and its hormones affects activity of other endocrine glands directly
usually control hormone releases
gland is sensitive to concentration of substances it regulates
hormone level rises, exerts effects and further secretion is inhibited by negative feedback and then hormone secretion decreases
concentration of hormones drops below normal levels and causes inhibition removed and gland secretes move again
hormone levels remain constant and fluctuate within a normal range
target gland stimulates hypothalamus or pituitary to increase hormone release
stimulates secretion of target gland
the release of oxyctocin is controlled through positive feedback