Lecture 21 Flashcards
What is the difference between tropic and trophic?
Tropic (aka:tropin) = affects other endocrine gland (tropic can be trophic) | trophic = affects growth
What are 4 significant things about the pineal gland?
true endocrine gland | makes melatonin | thought to store the soul | needs to get light signal through eyes or will easily cause depression
What role does the pineal gland play?
plays an important role in sleep/wake cycle
What are thyroid hormones used for? Are they essential for everyone?
needed for normal growth and development in children | adults do not need thyroid hormones or thyroid gland = can live without it
What do thyroid hormones have a long term effect on?
metabolism
What are the 2 thyroid hormones? Which one is the active one?
T3 and T4 | T3 = active one | need to convert T4 into T3
What happens to infants born with thyroid deficiency?
will be developmentally delayed, can be treated
What are amine hormones?
derived from tyrosine | contain iodine
What is the thyroid follicle?
in thyroid | makes thyroid hormones in the colloid = 2-3 month supply | single epithelial layer wall | filled with colloid
What is the Thyroid-Binding Globulin?
protein that circulates in blood | transports lipophilic T3 and T4 hormones
Where is the thyroid gland located?
under larynx, very vascularized
What secretes calcitonin?
C-cells in the thyroid gland
What is colloid?
glycoprotein
What is calcitonin?
hormone making bone denser
How many days is the half-life of iodine?
8 days
What is TRH and TSH?
thyrotropin releasing hormone | thyroid stimulating hormone
What is the origin and chemical nature of thyroid hormones?
from thyroid follicle (colloid) | iodinated amine
What is the half-life of T3 and T4?
T3 : 1 day | T4 : 6-7 days
What are 3 whole body/tissue reactions to thyroid hormones?
thermogenesis = increase O2 consumption | adults = protein breakdown | kids = protein building
What is catabolism and anabolism?
catabolism = breakdown (CAT=bulldozer) | anabolism = building
What is a Goiter? (3 characteristics)
excessive stimulation of TSH on thyroid gland = enlarges thyroid gland | not enough iodine in system | more T3 and T4 made
What is Myxedema?
hypothyroid people | deposits under skin = causes eye bags
What is Exophthalmos?
hyperthyroid people | bulging eyeballs
What is hyperthyroidism?
condition, excess production of T3 and T4
What mechanism of disease in Grave’s Disease?
thyroid-stimulating immunoglobulin = over synthesized »_space;> acts like TSH on thyroid gland = hyperthyroidism
What is Grave’s Disease?
a form of hyperthyroidism
Why doesn’t negative feedback work in Grave’s disease?
stimulation is not based on TSH = body senses TSH levels are normal | doesn’t measure TSI levels
What is thyroid-stimulating immunoglobulin (TSI)?
protein part of immune system
What is hypothyroidism due to?
low iodine
How does hypothyroidism cause a goiter?
T3 and T4 levels decrease = stimulates anterior pituitary to make more TSH | TSH buildup = enlarged thyroid gland
Where are parathyroid glands located?
4 glands behind thyroid gland
What is significant about parathyroid gland?
removal = causes death | makes parathyroid hormone | senses plasma calcium levels
What is the chemical nature of parathyroid hormone and its half-life?
peptide hormone | half-life = < 20 mins
What is the whole body/tissue reaction due to the parathyroid hormone?
increases plasma calcium
What triggers the release of parathyroid hormone?
decrease in plasma calcium from parathyroid glands
What are the 3 organs that parathyroid hormone act on?
bone | kidney | intestines
Where are the adrenal glands located?
on top of kidneys
What are the 2 embryonic tissues of adrenal glands?
adrenal cortex = outter (steroid hormones) | adrenal medulla = inner
What hormone stimulates the adrenal gland?
ACTH = adrenocorticotropic hormone
What are the 4 regions of the adrenal gland that secretes hormones?
zona glomerulosa | zona fasciculata | zona reticularis | adrenal medulla
In which region of the adrenal gland is aldosterone secreted?
zona glomerulosa
In which region of the adrenal gland are glucocorticoids secreted?
zona fasciculata | glucocorticoids = cortisol
In which region of the adrenal gland are sex hormones secreted?
zona reticularis
In which region of the adrenal gland are catecholamines secreted?
adrenal medulla | catecholamines = epinephrine
What are the 2 areas in which steroid hormones are made?
adrenal cortex | gonads
What molecule are steroid hormones made out of?
cholesterol
What are the 5 steroid hormones made from cholesterol?
aldosterone | progesterone | estradiol | testosterone | cortisol (stress hormone)
How does cortisol affect adipose tissue?
causes lipolysis = breakdown lipids
How does cortisol affect muscles?
protein catabolism = breakdown of protein
How does cortisol affect the liver?
gluconeogenesis = making glucose, byproduct = ketones
How does cortisol affect the immune system?
suppresses overresponse of immune system
