E4: thyroid Flashcards
endocrine glands general functions
- take up precursor molecules
- synthesize hormones
- store hormones
- release hormones into the ECF (rapid release)
general causes of endocrine gland problems
- glad dysfunction:
- failure of feedback system
- failure of receptors on target cells
what are three causes of gland dysfunction
- trauma/destruction
- tumors
- autoimmune
KNOW PG 4.12 OF HANDOUT PACKET
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which loop is the main loop
the short loop
hypothyroidism
deficiency of thyroid hormone resulting in slowed body metabolism (myxedema)
cause of hypothyrodism
- congenital (cretinism)
- post hyperthyroid treatment
- defective hormone synthesis (autoimmune, drug-induced, iodine def)
- insufficient stimulation
patho chain of hypothyroidism
hypothalamus–> T.R.H–> ant. pituitary–> TSH–> thyroid–> decreased T3, T4 to the cells–> decreased cell metabolism and decreased response to SNS stimulation
clinical mani of hypothyroidism
- enlarged thyroid (goiter)(thyroid increases mass due to TSH)
- related to slow body metabolism:
- –wt gain
- –dry skin and hair
- –lethargy
- –forgetfulness
- –depression
- –constipation
- –sensitivity to cold
- –slow movements
- –edema
- –decreased response to SNS=decreased HR
main feedback loop in hypothyroidism
short loop (main loop) something causes less thyroid hormones to be released into blood stream (t3-T4 –» ant pit to stimulate and increase production of TSH)(will cause an increase of TSH)
hyperthyroidism
excess thyroid hormone resulting in increased metabolic rate and an increased sensitivity to stimulation by the SNS
with hypothyroidism, what will lab values look like?
- low T3 and T4
- high TSH (prob with thyroid)
- low TSH ( prob above thyroid)
cause of hyperthyroidism
- tumors
- increased TSH
- genetic
- autoimmune
main feedback loop in hyperthyroidim
short loop: something causes too much thyroid hormone to be released causing an increased cell matabolism and increased response to SNS stimulation
(T3 and T4–» ant pit to inhibit production of TSH)
what are the labs going to look like in hyperthyroid if the problem is the thyroid itself
- increased T3, T4
- decreased TSH