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Flashcards in Endocrine Glands Deck (94)
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1
Q

what are the main cell type in the neurohypophysis?

A

pituicytes (astrocytic neuroglia)

2
Q

How is blood supplied to the adrenal glands?

A
  1. through medullary ateries (running directly from the capsule passing over cortex.. directly into the medulla) = have OXYGEN RICH HORMONE POOR blood 2. through capillaries that go THROUGH the cortex and eventually gets to the medulla as OXYGEN POOR HORMONE RICH blood and then dumps into veins
3
Q

what factor(s) stimulate/inhibit:TSH?

A

TRH (+)

4
Q

how do protein hormones act vs. steroid hormones? where are protein hormones produced vs. steroid hormones?

A

protein hormones: produced in Rough ER (to golgi to vesicles to release at cell surface); act on the cell surface receptros and exert their physiological effect via second messenger system steroid hormones: produced in smooth ER + mitochondria; act via binding to target cells’ DNA (intracellular receptor) and causing production of new proteins and hormone specific responses

4
Q

what does the zona reticularis of the adrenal cortex produce? is it dependent on ACTH?

A

gonadocorticoids mostly dehyroepiandrosterone; dependent on ACTH

5
Q

what type of cell is prolactin?

A

lactotrope or mammotrope

6
Q

what type of cells is ACTH?what percentage of the cells in the anterior pituitary?

A

Corticotrope (15%)

6
Q

what is the function of T3 and T4?

A

regulate tissue basal metabolism of carbohydrates, proteins, fats; heat production, body tissue growth and development

7
Q

how do glial and pinealocytes of the pineal gland differ histologically?

A

glial cells have a darker nuclei than pinealocytes

7
Q

what does the pineal gland function in?

A

secrete serotonin and melatonin to regulate gonadal function and circadian rhythm

8
Q

what is Thyrotropic Hormone (TSH) cell class: acidophil or basophil?

A

Basophil

8
Q

what is the function of ACTH?

A

stimulates production of glucocorticoids and gonadocorticoids in adrenal cortex

8
Q

what factor(s) stimulate/inhibit: ACTH ?

A

CRH (+)

8
Q

what is the clinical relevance of a pituitary adenoma on GH?

A

acromegaly in adults; gigantism in children

9
Q

what is the function of prolactin?

A

dtimulates mammary gland development and production of milk

9
Q

How is the thyroid gland arranged? what is stored in the different areas of its arrangement?

A

into spherical follicles; lumen of follicles is filled with colloid

9
Q

how does the adrenal cortex produce aldosterone?

A

in the z. glomerulus, cholesterol taken up and by receptor mediated endocytosis of LDLs and modifies it

11
Q

where is prolactin secreted from? what percentage of the cells in the anterior pituitary?

A

from adenophypophysis; 20%

12
Q

what is the histology of oxyphil cells?

A

get bigger andbigger (full of mitohondria) with aging.. therefore large eosinophilic cells

13
Q

where is the pituitary gland located?

A

attached to base of brain; lies within the sella turcica in sphenoid; covered by diaphragma sellae which is part of the dura mater

13
Q

what is the pituitary gland derived from?

A

adenohypophysis: from surface ectoderm (oral) from Rathke’s pouch neurohyophysis: from neural ectoderm from the floor of diencephalon (proenceph)

13
Q

what does the colloid inside the lumen of the thyroid gland’s lumen represent?

A

the stored secretory product of the follicular cells

14
Q

do endocrine glands have ducts?

A

NO

15
Q

what is Adrenocorticotropic hormone (ACTH) cell class: acidophil or basophil?

A

Basophil

16
Q

what is unique about the development of the pineal gland?

A

it forms as an extension on the dorsal posterior part of the roof of the diencephalon and is coered by a capsule; it is continuous with the pia mater and extends into the gland as septa and trabeculae

17
Q

what type of cells are present in the thyroid gland?

A

thyroid follicular and parafollicular cells (c-cells)

18
Q

what stimulates GH? what inhibits GH?

A

GNRH = + somatostatin = -

19
Q

what are the cell types in the parathyroid gland?

A
  1. principal/cheif cells 2. oxyphil cells
20
Q

which of the layers of the adrenal cortex is basophilic? eosinophilic?

A

z. glomerulosa = basophilic z.fasiculata = eosinophilic Z. reticularis = both (2-toned)

22
Q

what is the function of LH and FSH?

A

stimulate follicle development in ovary and spermatogenesis in testis

23
Q

what is the clinical relevance of a pituitary adenoma on FSH and LH

A

often no symptoms

24
Q

what is the synthesis of PNMT induced by? why does this make sense?

A

induced by glucocorticoids; come from the venous drainage from the zona fasiculata (through the series of capillaries… hormone rich, oxygen poor)

24
Q

What is Cushings syndrome? symptoms?

A

Hyperadrenocorticism; increaed activity of adrenal cortex leads to obesity, hirsutism, moon face, thinning of skin, and lipodystrophy

25
Q

do thyroid parafollicular cells make any contact with the lumen of the follicle

A

NO

26
Q

which do you have more of ? T3 or T4?

A

T4

28
Q

Cell class, cell type, location of secretion in pituitary, and hypothalamic regulator of: Growth Hormone

A

Acidophil; somatotrope, 50% of cells released from adenophypophysis, GNRH stimulates GH; Somatostatin inhibts GH

29
Q

what is Thyrotropic Hormone (TSH) cell typewhat percentage of the cells in the anterior pituitary?

A

thryotrope (5%)

29
Q

what factor(s) stimulate/inhibit:prolactin?

A

TRH (+) dopamine (-)

30
Q

how many endocrine organs are on each adrenal gland?

A

2: adrenal cortex + adrenal medulla

31
Q

what converts norepinephrine to epinephrine?

A

PMNT (phenylethanolamine N-methyltransferase)

33
Q

what factor(s) stimulate/inhibit: FSH / LH

A

GnRH (+)

34
Q

how does blood flow from the z. fasiculata to the z. reticularis?

A

via fenestrated capillaries

35
Q

what is FSH and LH cell class: acidophil or basophil?

A

Basophil

35
Q

what is oxytocin’s target organ?

A

uterine smooth muscle, mammary gland, myoepithelial cells

36
Q

What hormones are secreted from the pars nervousa?

A

ADH, Oxytocin

37
Q

what is the function of TSH?

A

stimulates production of thyroid hormone

38
Q

what is found in the adrenal medulla?

A

post ganglionic neurons WITHOUT THEIR AXONS

39
Q

what types of cells are FSH and LHwhat percentage of the cells in the anterior pituitary?

A

Gonadotrope (10%)

39
Q

what is ADH’s target organ

A

collecting ducts of kidney for increased water resorption

39
Q

what does the adrenal medulla produce?

A

80% = epinephrine 20% norepinephrine

41
Q

what cells and what type of material are very prevalent in pars intermedia?

A

contains colloid filled cysts; BASOPHILS + CHROMOPHOBES

41
Q

where are the adrenal glands located?

A

on top of kidneys

42
Q

what is the function of aldosterone? is it dependent of ACTH?

A

increases sodium uptake in order to increase blood pressure; INDEPENDENT OF ACTH

43
Q

where is aldosterone produced?

A

in the zona glomerulosa of the adrenal cortex

45
Q

what is unique about the thyroid gland’s hormone storage?

A

stores its product outside the cell

47
Q

what are the triggering agents of ADH release?

A

increase in plasma osmolality and decrease in blood volume

48
Q

what type of mitochondria is found in the z. fasiculata?

A

tubulolike becuase lots of sER

49
Q

what is the clinical relevance of a pituitary adenoma on PRL?

A

galactorrhea, hypogonadism, amenorrhea, infertility, impotence

51
Q

what is corpora arenacea?

A

aka brain sand or acervuli; concentrations of calcium phosphate salts that increase with age; useful as a radiological landmark

52
Q

where are the veins located in the adrenal gland?

A

in the MEDULLA. no veins in the cortex

54
Q

Describe the blood supply of the posterior pituitary

A

INFERIOR hypophyseal branches of internal carotid supply the pars nervous; –> gives rise to a set of FENESTRATED capillaries that drain into hypophyseal veins into cavernous sinus

56
Q

what is the function of ADH (vassopressin)

A

increase blood pressure and retain fluid in kidne

58
Q

what is the pars intermedia a remenant of?

A

rathke’s pouch

59
Q

what is the function of principal/cheif cells?

A

produce parathyroid horomone to increase blood calcium levels

60
Q

what is unique to the histology of parathyroid glands? how can you tell the age of the specimen?

A

have fat cells; increase in fat content with age

61
Q

what type of vasculature surrounds each follicle of the thyroid gland?

A

fenestrated capillariesw

62
Q

What is Addison’s Disease? symptoms?

A

Hpoadrenocorticism.. destruction of adrenal cortex (sometimes by tuberculosis) leading to weakness, weight loss, LOW BP, increased secretion of ACTH causes increased skin pigmentations

63
Q

what is the function of cortisol? is it dependent on ACTH

A

promotes metabolism and suppresses inflammatory response; an ACTH dependent

65
Q

what hormones are secreted from the pars distalis?

A

Acidophills (prolactin + Growth Hormone); Basophils (TSH, ACTH, FSH, LH) FLAT PG

66
Q

where are glucocorticoids (ie: cortisol) produced?

A

z. fasiculata of adrenal cortex

66
Q

What is pheochromocytomas? symptoms?

A

tumors of the adrenal medulla that leads to hypertension, elevated heart rate, anxiety, weight loss

68
Q

what do pinealocytes secrete? what is a unique structural characteristic of theirs?

A

produce and secrete serotonin and melatonin; have a lighter nuclei than the glial cells of the pineal gland; have long cytoplasmic processes with club shaped terminations

70
Q

what are the different zones of the adrenal gland?

A

from superficial to deep (towards the medulla) zona glomerulosa zona fasiculata zona reticularis

71
Q

what is the clinical relevance of a pituitary adenoma on ACTH

A

Cushings disease

73
Q

Describe the blood supply of the anterior pituitary

A

SUPERIOR hypophyseal arteries, branches of the internal carotids and the circle of willis, supply blood hypophseal portal system which follows: go to medial eminance then to capillary beds (blood picks up more hormones) then to another plexus (via vein) then to hypophyseal and then to cavernous sinus

74
Q

what are all of the stages of T3 and T4 hormone controlled by?

A

TSH ( which is regulated by TRH)

75
Q

what does aldosterone depend on?

A

angiotensin II

76
Q

what triggers oxytocin release?

A

neural stimuli to hypothalamus

77
Q

what is the function of thyroid parafollicular cells?

A

produce calcitonin (tones down calcium): decreases blood calcium levels

78
Q

How is thyroid hormone produced?

A

1.follicular cells concentrate Iodine (I) via ATP-depenedent iodide transporters 2. Rough ER synthesized thyroglobulin peptides, adds mannose and glucoasmine 3. glogi condenses the protein, adds galactose, fructose, and mannose 4. thyroglobulin is released by exocytosis into the follicle lumen 5. Thyroid peroxidase (produced by follicular cell) oxidizes iodide to free iodine so it can now couple with tyrosine in thyroglobulin to form mono and di-iodothyroinin (TWO IODINE = T4, ONE IODINE = T3) 6.stored as colloid and released into the blood for transport

80
Q

what is the function of growth hormone (somatoropin)

A

stimulates growth through insulin-like growth factor 1 (1GF-1)

81
Q

where are oxytocin and ADH released from?

A

pars nervosa

82
Q

what hormones are secreted from the Pars Intermedia?

A

ACTH, MSH

83
Q

are products of the adrenal glands stored in vesicles? why?

A

adrenal cortex = no vesicles (steroid product) adrenal medulla = yes vesicle (protein product)

84
Q

what type of mitochondria in the zona glomerulosa

A

SHELF LIKE (z.glomerulosa produces aldosterone )

85
Q

what is the clinical relevance of a pituitary adenoma on TSH?

A

hyperthyroidism– no symptoms

86
Q

what are the 2 primary and 5 secondary divisions of the pituitary?

A

Adenohypophsis (pars distalis, pars intermeditus, pars tuberalis) and Neurophysisis (pars nervosa + infundibulum)

87
Q

what type of cells line the follicles of the thyroid gland?

A

simple cuboidal epithelium

89
Q

Describe the hormone release system of the neurohypophysis

A

ADH and Oxytocin are produced in the supraoptic/paraventricular cell bodies; ADH + O are then packaged into vesicles that travel down to the neurohypophsysis (NH), attached to neurophysin and ATP; neurophysin is cleaved en route to the axon terminal release site; reach herring bodies (dilations with lots of vesicles of ADH OR Oxy)

90
Q

what is prolactin (PRL) cell class: acidophil or basophil?

A

Acidophil

91
Q

what stains the adrenal medulla? why?

A

dichromate salts; because of chromaffin system of cells

92
Q

How is the pars distalis controlled by the hypothalamus?

A

fibers from specific hypthalamic areas (tuberal nuclei) terminate in the infundibular stalk; their neurons produce releasing factors that are carried to the adenohypophysis via portal vessels and stimulate/ inhibit hormone release

93
Q

what do the thyroid follicular cells produce? how are the products stored?

A

thyroxin (T4) and triiodothyronine (T3); stored extracellularly

94
Q

The neurophysis serves as a neurosecretory site for neurons whose cell bodies are in the _____ and _____ nuclei of the hypothalamus

A

supraoptic and paraventricular