THYROID GLAND MIDTERM CC2

thyroid gland

located in front of the lower neck

thyroid gland

bow tie or butterfly like

follicles

structural units of thyroid gland

colloid

thyroglobin

__________________: homogenous viscous fluid consisting mainly glycoprotein iodine complex called ___________

t3, t4 and calcitonin

thyoid gland secretes

t3 and t4

follicular cells

food (t3 and t4)

control the rate at which cells burn fuels from _____________ for energy

CNS and brain

follicular cells: t3 and t4

_________________ activity and ______________ development

cardiovascular

bone and tissue

follicular cells: t3 and t4

__________________ stimulation. __________ and ________________ growth and development

gastrointestinal and sexual maturation

follicular cells: t3 and t4

________________ regulation and _______________ maturation

calcitonin

parafollicular cells (c-cells):

calcium

calcitonin: regulation of

99.8%

how many percent is t3 in bound (albumin, prealbumin and globulin)

99.98%

how many percent if t4 in bound (albumin, prealbumin and globulin)

0.2%

how many percent is t3 in free

0.02%

how many percent is t4 in free

globulin and albumin only

t3- ____________ and ____________ only

10%

30% TBPA

60% TBG

t4: albumin (_____________)

prealbumin (______________)

globulin (______________)

hypothalamus TRH -----> pituitary gland TSH ---------> thyroid gland (t3 and t4)

mechanism for the production of thyroid hormone

1. for tissue growth

2. for development of CNS

3. elevated heat production

4. control oxygen consumption

5. it infleunce carbohydrate and protein metabolism

6. for energy conservation

thyroid hormones function

3,5,5' triiodothyronine

t3 is also known as

t3 (triiodothyronine)

it has the most active thyroid hormonal activity.

75%-80% (tissue deiodination

t3 is almost _______________ is produced fromt the _______________ of t4

t3 thyrotoxicosis

t3 principal application is in diagnosing ________________

hyperthyroidism

t3 better indicator of recovery from _____________ (as well as recurrence)

80-200 ng/dl

1.2-3.1 mmol/l

reference value of t3 in adults

105-245 ng/dl

1.8-3.8 mmol/l

reference value of t3 in children 1-14 years old

3,5, 3'5 tetraiodothyronine

t4 is also known as

t4 (tetraiodothyronine)

principal secretory product

t4 (tetraiodothyronine

the major fraction of organic iodine in the circulation

t4 (for t3 production)

t3 is a prehromone for ______________

thyroid gland

all circulating t4 originates in the

5.5-12.5 ug/dl

71-161 mmol/l

reference value for t4 in adult

11.8-22.6 ug/dl

152-292 mmol/l

reference value of t4 in children

iodine

______________ is the most important element in the biosynthesis of thyroid hormones

50%

iodine intake below _______________ can cause deficiency

monoiodotyrosine (MIT) and diiodotyrosine (DIT)

iodination of tyrosine residues in the thyroglobulin results in formation of ________________ and __________________

many tissues

conversion of t4 to t3 takes place to ___________

metabolically inactive

protein bound hormones are ______________

one iodine from inner ring

reverse t3 is produced by removal of ____________________ from ______________ of t4 (product of t4 metabolism

very long time

latent period:

t3 and t4 have a ___________________ period before effect

12 hours

t3 around

72 hours

t4 around

2 days

biological half life of t3

7 to 9 days

biological half life of t4

basal metabollic rate (BMR)

main action of T3 and T4

increase ________________________

carbohydrate, protein and fat metabolism

main action of t3 and t4

increase _______________, _____________ and ____________

catecholamines

main action of t3 and t4:

potentiate action of the _____________

endocrine system

main action of t3 and t4:

interaction with other ___________

CNS

main action of t3 and t4

effect on the ___________

vitamin A and retinal synthesis

main action of t3 and t4

increase _______________ and _______________

agenesis

complete absence

incomplete descent

from base of tongue of trachea

lingual thyroid

complete failure to descent from base of tongue

thyroglossal cyst

segment of duct persists and presents as lump for years later

hyperthyroidism

refers to an excess of circulating thyroid hormone

slim and thin (due to calorie burning)

hyperthyroidism most patients are ____________ and __________ (due to ______________)

appetite and weight

hyperthyroidism increase _____________ and decrease ____________

exophthalmia

hyperthyroidism presence of ______________

1. heat intolerance

2. increase activity

3. tachycardia

hyperthyroidism last 3 conditions

hypothyroidism

develops whenever insufficient amount of thyroid hormone are available to tissues

obese

hypothyroidism patients are _______________ in nature

appetite and body weight

hypothyroidism decrease in _____________, increase in _____________

edomatous cholesterol level

hypothyroidism _________________; increase in _____________

cold intolerance

decreased activity

hypothroidism last 2 conditions

thyrotoxicosis

overactive thyroid gland makes too much thyroxine

thyrotoxicosis

applied to a group of syndromes caused by high levels of free thyroid hormones in the circulation

low

normal

increase (plummer's disease)

(thyrotoxicosis)

TSH is _________________, FT4 is ________________ but _________________ ft3-> t3 thyrotoxicosis (________________)

1. mood swings

2. restless

3. sleep difficultiews

4. tremor of hands

5. palpitations

6. sore eyes (sensitivity, irritations and trouble focusing

7. goiter

features of thyrotoxicosis

grave's disease

hyperthyroidism with peculiar edema behind the eyes called exolphthalmos which causes the eye to protrude

thyroid stimulating immunoglobulins

grave's disease hypersecretion of ______________________

smoothly enlarged and overactive

(grave'sdisease) autoimmune disease:

whole gland is _______________________ and the whole gland is _______________

6x

grave's diseae occurs _____________ more commonly in woman than in men

grave's disease

_____________ receptors antibodies

1. exophthalmos

2. pritibial myxedema

features of grave's disease

Riedel's thyroditis (reidel's trauma)

the thyroid turns into a woody or stony hard mass

low and normal

shows no clinical symptoms but TSH level is ______________, and t3 and t4 is ________________

subacute granulomatous

associated with neck pain, low grade fever and swing in thyroid function test

thyroid peroxidase antibodies

in subacute granulomatous this antibodies are absent

ESR and thyroglobulin

subacute granulomatous

___________ and _____________ levels are elevated

myxedema

caused by autoimmune damage to the thyroid, or surgical removal

underactive

myxedema:

_______________ thyroid gland

nonpitting swelling

myxedema:

describe the peculiar ______________________ of the skin

mucopolysaccharides

myxedema:

the skin becomes infiltrated by ________________

thyroxine secretion

myxedema

primary thyroid failure -> decline in _______________ secretion by thyroid gland

anterior pituitary gland and secretes TSH

myxedema

__________________ detects this fall and secretes ______________

1. decreases BMR

2. deepening of voice

3. depression and tiredness

4. cold intolerance (puffy face)

5. anemia

6. weight loss

7. slow speech

8. dry, yellow skin

9. constipation

10. bradycardia

11. eventual myxedema coma

clinical features of myxedema

chronic autoimmune thyroiditis

hashimoto' disease other name

hashimoto's disease

the common cause of primary hypothyroidism

1912

described by hashimoto in

hashimoto's disease (antibody mediated immune response)

an autoimmune disease in which thyroid gland is attacked by variety of __________________

lymphoid tissue

hashimoto's disease

the thyroid is replaced by a nest of ____________

goiter

associated with enlargement of the thyroid gland

autoantibodies (hashimoto's disease

acquired hypothyroidism in later childhood due to development of ___________ to thyroid tissue components

cretinism (iodine)

is a condition of severely stunted physical and mental growth due to untreated congenital deficiency of thyroid hormones (congenital hypothyroidism) due to maternal nutritional deficiency to ____________

physical and mental

cretinism

_____________ and ___________ retardation

t4 (decreased)

screening test for cretinism

TSH (increased)

confirmatory test for cretinism

heel prick blood test

cretinism prevention:

babies at 5 to 10 days have ________________

thyroid function (thyroxine)

cretinism prevention

_________________________ -measures TSH; if TSH is high ___________ is given immediately