hormones are slow to act some even months to years!
hormones are blood borne
hormones are also neurotransmitters
ENDOCRINE GLANDS
organs that produce endocrine hormones :: hypothalamus, pineal gland, pituitary gland, thyroid gland, adrenal glands, pancreas, ovary, testes
PATHOLOGY ASSOCIATED WITH THE ENDOCRINE SYSTEM
gigantism :: due to hypersecretion of growth hormone
Cushing's syndrome :: due to hypersecretion of cortisol (stress hormone). can cause type 2 diabetes bc its a glucocorticoid
hypothyroidism :: due to dec amt of circulating thyroid hormone. iodine deficiency. can cause a goiter.
HORMONES ARE EVERYWHERE
many hormones are for cellular communication
leptin :: as adipocytes inc, leptin inc which signals to the brain that there is a lot of energy available for use
ghrelin :: when the stomach / small intestine are empty they produce ghrelin to signal to the hypothalamus to make you feel hungry
HORMONE ACTION
hormones can act in 3 different fashions
endocrine fashion :: acting at a great distance in the body
paracrine fashion :: acting nearby the target cells ex. prostaglandins and nitric oxide
autocrine fashion :: acts on it self ex. growth factor IGF1
SIGNAL TRANSDUCTION FOR HORMONES
hydrophilic hormones :: cannot go through the plasma membrane thus the cells tend to cell-surface receptors ex. oxytocin and insulin; moves in the blood easily
* second messenger :: water-soluble hormones cause these to produce within the cell to tell it to do smth. it amplifies the signal
lipophilic hormones :: can through the plasma membrane of a cell so it uses a intracellular receptor ex. estrogen and testosterone