This site is 100% ad supported. Please add an exception to adblock for this site.

Lecture 32


undefined, object
copy deck
Action of Thyroid hormone
-almost all organs in body are target of thyroid hormone; it increases protein synthesis and cell respiration; thus increasing metabolic rate (by stimulating the synthesis of uncoupling proteins; these dissociate electron transport and ATP synthesis; lead
Activation of Adrenal medulla
-adrenal gland innervated by sympathetic neurons so its activated when sympathetic ns is activated (during fight/flight)
Addison's Disease
-hyposecretion (too little) of corticosteroids and mineralocorticoids; leads to low blood glucose; Na and K imbalance; and weakness
Adrenal Cortex
-cells here secrete 3 different kinds of sterooid hormones -collectively called corticosteroids or corticoids
Adrenal Medulla
-secretes epinephrine and norephinephrine; similar to effect of sympathetic nervous system activation but lasts longer (increase heart rate, resp rate, blood glucose, etc)
-steroid hormone secreted by adrenal cortex -involved in regulation of metabolism -ex: cortisol; regulated by release of ACTH from anterior pituitary -cortisol raises level of glucose and other energy rich molecules in blood -cortisol results in
Location of Adrenal Glands
Paired organs that cap superior borders of kidneys
Melatonin and Circadian Rhythm
-circadian rhythm (24 hour patterned period) -night-> activity of SCN rises (more melatonin secreted)
-steroid hormone secreted by adrenal cortex -regulate amt of Na and K in body -ex: aldosterone acts on kidneys -causes kidneys to retain Na and water and loose K in urine -affects circulatory system *increases blood pressure and volume; regulates
pineal gland
-found in brain; secretes hormone called melatonin; secretion of melatonin shows a circadian rhythm
Role of pineal gland in regulation of emotional state
-SAD-seasonal affective disorder -depression when days get shorter, improved by light exposure -SAD affects 20% of pop of Alaska; only 2.5% in Florida -melatonin level is high in SAD patients (but reduced by light exposure)
Role of Pineal Gland in sexual development
-inhibits GnRH secretion
sex steroids
-steroid hormone secreted by adrenal cortex -supplemental source in addition to the gonads
Stress response of adrenal gland
-ALARM: adrenal medulla is activated (prepares body for fight/flight) -RESISTANCE: adrenal cortex is active (-cortisol release-> breakdown of fat; -cortisol inhibits protein synthesis->immune system is suppressed) -EXHAUSTION: adrenal cortex becomes ina
Structure of Adrenal Glands
-outer cortex and inner cortex -have different functions -origin of cells of medulla made from the same tissue that makes sympathetic neurons -so cells of medulla and sympathetic neurons are very similar
T3 and T4 Travel Methods
-travel to target cells in blood attached to carrier proteins; once free of carrier T4 can enter cells; in cells T4 is converted to T3 (the active form)
thyroid glands
-secrete thyroid hormone (molecules T3 and T4 collectively; thyroid follicles take iodide from blood and secrete it into the interior of the thyroid gland; it is used to make hormones called T3 and T4; release of T3 and T4 triggered by stimulation by TSH
thyroid goiter
-effect of change in secretion of thyroid hormone; too little iodine in diet; abnormal growth of thyroid gland; symptoms include low bmr and large thyroid gland
Transport of thyroid hormone
-lipid soluble; diffuses across cell membrane and acts in nucleus of target cells where it regulates gene transcription; like a steroid hormone, thyroid hormone acts via nucleus
Treatment of Addison's Disease
-use of glucocortisoids and mineralocorticoids; test for hormone that regulates adrenal cortex
Tumor of Adrenal Medulla
-result of hypersecretion (too much) of epinephrine and norepinephrine; symptoms are hypertension and high blood glucose

Deck Info