Pituitary and Hypothalamus Flashcards
(138 cards)
1
Q
What form the andohypothysis?
A
oral ectoderm
Rathke’s pouch
2
Q
What is the embryonic tissue that form the neurohypophysis?
A
Neuroectoderm
from the hypothalamus
3
Q
Which arteries to the pit. supply the pars tubercalis, median eminence, and infundibulum?
A
Superior hypophyseal aa.
4
Q
What area of the pit. does the inferior hypohyseal aa supply>
A
posterior pit (pars nervosa)
5
Q
Match the following cell types to the hormones.
- Somatotropes
- Lactotropes
- Corticotropes
- Gonadotropes
- Thyrotropes
A. FSH/LH B. GH C. PRL D. TSH E. ACTH
A
- B
- C
- E
- A
- D
6
Q
Which 4 of the 6 adenohypophysis (AHP) hormons are trophic?
A
ACTH
TSH
FSH
LH
(GH and PRL act directly on target organs)
7
Q
Which 2 AHP H’s stain as an acidophile?
A
Somatotrope (GH)
Lactotrope (PRL)
(the non-trophic hormones)
8
Q
What is the stain that is specific for the acidophiles?
A
Orange G
9
Q
What are the 3 cell types of the AHP that are basophilic and PAS+?
A
Corticotrope (ACTH)
Gonadotrope (FSH and LH)
Thyrotrope (TSH)
10
Q
Put the following cell types in order from most to least abuntant in the AHP.
ACTH PRL FSH/LH GH TSH
A
TSH (50%) > PRL = ACTH (15-20%) > FSH/LH (10%) > TSH (5%)
11
Q
What are the 2 hormones secreted from the NHP?
A
ADH
Oxytocin
12
Q
What big molecules is cleaved to make ACTH and B-LPH?
A
POMC
13
Q
What is the hypothalamic hormone that stimulates the somatotropes?
A
GHRH
14
Q
What is the hormone from the hypothalamus that inhibits the somatotropes and insulin secretion by B cells of the pancreas?
A
Somatostatin
15
Q
What is the hypothalamic H that inhibits the lactotropes?
A
Dopamine
16
Q
What is the hypothalamic H that stimulates the corticotropes?
A
CRH
17
Q
What is the hypothalamic H that stimulates the gonadotropes?
A
GnRH
18
Q
What is the hypothalamic H that stimulates the thyrotropes?
A
TRH
19
Q
What is the name of the sytstem that connects the hypothalamus to the AHP?
A
Hypothalamic-hypophysial portal system
20
Q
What mediates the effect of GH on the tissue, and is synthesized in the liver?
A
IGF-1
21
Q
What are the 5 actions of GH on proteins?
A
Proteins --> tissue AA --> cell membranes ↑ protein synthesis ↑ DNA txn ↓ catabolism of proteins
22
Q
What is the main action of GH on adipose tissue?
A
GH ↑ the relase of FA’s form fat –> body fluids
23
Q
So under the whip of GH, what is the main source of energy?
A
Fat
this is why u get skinny during puberty
24
Q
What is the hormone that GH hates and is willing to put a plentiful bounty on its head?
A
Insulin
25
What are the 3 main actions of GH on carbohydrate metabolism?
Think anti-insulin, or "glucagon" effects.
1. ↓ glucose uptake into tissues
2. Increase glucose production by the liver
3. increase insulin secretion
26
So yeah, GH puts a lot of glucose and therefore insulin into the blood, but what can GH cause to bitchslap insulin's effects?
Insulin resistance
| similar to DMII
27
What are the molecuels that are made in the liver in repsonse to GH, mediates GH effects, and binds tighter than GH to plasma proteins?
Somatomedins (IGF-1)
28
What happens to GH levels under starvation, hypoglycemia, exercise, excitement, or trauma?
it ↑
29
This is the condition where there are excessively active, acidophilic, GH-producing cells in kids.
Gigantism
30
Which famous person has gigantism?
Yo mama
31
This is the condition from an acidophilic tumor that occurs after adolescence.
Acromegaly
32
Since bones can't grow taller in acromegaly, what happens to them?
They get thicker
33
Which famous person has acromegaly?
Jaws from James Bond
His only line in all the movies is in Moonraker right before he dies and he says "Well, here's to us."
34
When should u use recombinant GH as a treatment?
Hyposecretion of GH
35
What is the treamtent for the hypersecretion of GH?
Removal of tumor
36
What are the glial cells called in the posterior pituitary called?
Pituicytes
37
Which nucleus makes ADH? Oxytocin?
ADH- Supraoptic nucleus
| OTX- Paraventricular nucleus
38
What is the stimulus for ADH release from the hypothalamus?
↑ osmolarity of extracellular fluid
39
What does ADH do to the collecting duct?
inserts Aq into luminal membrane --> water reabsorption
40
What does ADH also do to blood vessels?
Vasoconstriction
| remember the other name of ADH is "vasopressin"
41
What stimulates the hypothalamus to produce OTX to contract the uterus?
Stimulation of the cervix
42
What stimulates the paraventricular and supraoptic nuclei in the hypothalamus to release OTX, which causes myoepithelial cells around the mammary glands to contract, and thus milk flows?
Suckling of the nipple
43
So in essence, what are the 2 main actions of OTX?
Uterine contraction
| Milk exporation
44
What are the 2 forms of pituitary adenomas?
Functional (hormone-producing)
| Nonfunctional (silent)
45
What are the visual problems with a nonfunctional pituitary adenoma?
Bitemporal hemianopsia due to compression of the optic chiasm
46
What are the Sx of a prolactinoma in women?
Galactorrhea
| Amenorrhea
47
What are the Sx of prolactinoma in men?
↓ libido
| Headaches
48
True or False: prolactinomas are the most common type of pituitary adenoma.
True!
49
What are the 2 dopamine agonists in the treatment of a prolactinoma?
bromocriptine or cabergoline
50
What is the treatment for large prolactinomas?
CUT IT OUT
51
What happens to GH levels in a GH adenoma if you give glucose?
They don't change
| normally they'd ↓
52
What is the somatostatin analogue that supresses GH release in the treament of GH adenomas?
Octreotide
53
What is the syndrome called from ACTH adneomas?
Cushings
54
How much of the pituitary parenchyma must u lose to show Sx in hypopituitiarism?
> 65%
55
What is a common cause of hypopituitarism in adults? Kids?
Adults- adenomas
| KIds- craniopharyngiomas
56
This is a pregnancy-related infarction of the pituitary gland, where there is blood loss during parturition.
Sheehan syndrome
57
What are the 3 major Sx to Sheehan syndrome?
Poor lactation
Loss of pubic hair
Fatigue
58
This is the cause of hypopituitarism where there is a congenital defect in the sella, where there is herniation of the arachnoid and CSF into sells --> destroys pit.
Empty sella syndrome
59
This is the condition where there is an ADH deficiency due to hypothalamic or NHP pathology.
Central diabetes insipidus (DI)
60
What are the urine, salt, and osmolarity changes in central DI?
Polyuria/polydipsia
Hypernatremia
Low urine osm and specific gravity
61
What is the result of water deprivation tests in central DI?
They FAIL to increase urine osmolality
62
What is the DOC for central DI?
Desmopressin (ADH analog)
63
This is the condition where there is impaired renal response to ADH, usually from inherited mutations or drugs.
Nephrogenic DI
64
What are the 2 common drugs to cause nephrogenic DI?
Li
| Demeclocycline
65
True or False: in nephrogenic DI, there is adequate response to Demopressin like there is in central DI.
FALSE
Central DI has a response and nephrogenic DI has no response. Remember in central, you can't MAKE ADH, and the kidneys are fine, so replacement therapy is good. In nephrogenic, the ADH levels in the blood are fine but the kidney can't respond to it, so it doesnt matter if u inject more ADH because the kidney will be like "yes, i still suck"
66
This is the condition where there is retenton of free water, leading to hyponatremia, low serum osmolality, mental status changes, and seizures.
SIADH
67
In addition to trauma, infection, and drugs like cyclophosphamide, what is the important cause of SIADH?
Ectopic production (like small cell carcinoma of the lung)
68
What are the 2 treatments for SIADH?
Free water restriction
| Demeclocycline
69
Where are craniopharyngiomas derived from?
Rathke's pouch
70
Which form of craniopharyngiomas have dystrophic calcifications, palisading squamous epithelium, lamellar/wet keratin, and there is a cholesterol-rich, thick brownish-yellow fluid?
Adamantinomatous craniopharyngiomas
| kids
71
What form of craniopharyngiomas are in adults, and rarely calcifies?
Papillary craniopharyngiomas
72
What is the gland between the superior colliculi at the base of the brain, composed of cells with photosensory and neuroendocrine fxns?
Pineal gland
73
What is the main product of the pineal gland to regulate the circadian rhythms?
Melatonin
74
What are teh 2 forms of pinealomas?
Pineoblastomas
| Pineocytomas
75
What are the all the hormones involved in the cortisol pathway?
CRH from hypothal --> ACTH from AHP --> Cortisol from adrenal
76
What are the all the hormones involved in the GH pathway?
Ghrelin and GHRH stimulate AHP to release GH --> GH stimulates liver to make IGF-1
Somatostain inhibits GHRH receptors
77
In growth hormone insensitivity, waht is the 1 pathway that's enhanced?
lack of IGF-1 release from liver --> ↑ GH from AHP
78
In secondary growth hormone insensitivity, waht is the 1 pathway that's reduced?
↓ GH release from AHP
79
In tertiary growth hormone insensitivity, what 2 hormones are reduced?
Ghrelin + GHRH
| therefore no AHP stimulation
80
What is the drug that is a GHRH analogue, and enhanced basal and pulsatile GH secretion?
Tesamorelin
81
Which form of GH insensitivity is Tesamorelin indicated?
tertiary insensitivity
82
What are the 2 adult contiditons that are indications for recombinant HGH (somatotropin)?
GH deficiency
| Panhypopituitarism
83
What are the 4 kid conditions that are indications for recombinant HGH (somatotropin)?
Idiopathic short stature
Chronic kidney disease
Turners syndrome
PW syndrome
84
Patients with GH insensitivity (Larson dwarfism) or GH deficiency and Ab's against GH are indications for the use of which drug?
Mecasermin
85
What are the Sx of acromegaly?
organomegaly, macroglossia, large facial features, increased hand/feet thickness, hyperhidrosis, fatigue
86
What are the 2 somatostatin analogues?
Octreotide
| Lanreotide
87
What is the GH analogue that has been modified in a way that one of the sites binds to the GH receptor w/ higher affinity than the native molecule, but the other binding site is inactive.
Pegvisomant
88
What is the indication for Pegvisomant?
2n3 or 3rd line after SRL therapy has been attempted for somatotroph adenomas
89
What is the prolactin pathway?
TRH from hypothal --> PRL from AHP --> lactation
Estrogen stimulates PRL
Dopamine inhibits PRL
90
Why do phenothiazine antipsychotics or metoclopramide elevate prolactin levels?
They're D antagonists
91
How soon does the initiation of breastfeeding cause the release of prolactin?
30 mins
92
Since prolactin suppresses estrogen synthesis, which thus ↓ FSH/LH, what is the common problem in ↑ prolactin levles?
Infertility w/ oligomenorrhea or amenorrhea
93
What is the synthetic dopamine agonist that inhibits lactotroph cell growth, which is used to treat prolactinomas?
Bromocriptine
94
What is another dopamine receptor agonist that i used to treat prolactinomas?
Cabergoline
95
What is the main test used in screening for pirmary thyroid disease?
Serum TSH
96
What will cause ↑ TSH? ↓ TSH?
↑ TSH- primary thyroid problem
| ↓ TSH- secondary problem (with AHP or hypothal)
97
Which nucleus of the hypothalamus makes CRH?
Paraventricular nucleus
98
MSH, Liptropin, B-endotropin, and ACTH are from what big molecule?
POMC
99
What drug is a synthetic analogue of ACTH?
Cosyntropin
100
What will be the result of Cosyntropin treatment in primary adrenal insufficiency?
No increase in plasma cortisol.
101
What will be the result of Cosyntropin treatment in new onset adrenal insufficiency?
↑ plasma cortisol
102
What will be the result of Cosyntropin treatment in long standing adrenal insufficiency?
Blunted cortisol response b/c of progressive adrenal cortical atrophy
103
What is the mechanism and indication for Tolvaptin?
V2 antagonist of ADH
for heart failure
104
Conivaptan is used for euvolemic and hypervolemic hyponatremia because it has what mechansism of action?
Mixed V1a and V2 antagonist
105
What are the 2 drugs for the treatment of pts with nephrogenic DI?
Amiloride (K-sparing) or hydrochlorothiazide
106
What 2 smooth muscles are contracted by OXT?
Boob
| Uterus
107
Pituitary tumors or surgery and radiotherapy can cause what condition?
Hypopituitarism
108
What happens to tesosterone or estradiol levels in the gonadotrophin axis in hypopituitarism?
they ↓
109
Which H is ↓ in the Dx of central hypothyroidism?
T4
110
What is the test u can do to stimulate GH secretion?
Insulin-induced hypoglycemia
111
What is the hormone replaced in ACTH deficiency?
Glucocorticoid replacement
112
What is the DOC for TSH deficiency?
Levothyroxine sodium
113
What are the 2 components of the "pill"?
Estrogen + progesterone
114
What is the H replacement for gonadotrophin deficiency in males?
Testosterone
115
What is the difference between microadenomas vs macroadenomas?
Mico are < 1cm
Macro are > 1 cm
116
What are the hypothalamic syndrome signs from a pituitary tumor?
disturbed thirst, satiety, sleep and temperature regulation
117
Which CN's can be compressed in a pituitary tumor? Sx?
III, IV, VI --> diplopia + strabismus
118
Pituitary tumors can cause CSF draining from which orifice?
Nose
| CSF rhinorrhea
119
What is the surgery for removal of most pit tumors?
Transsphenoidal surgery
120
Pregnancy, postpartum state, stress, and functional disorders can cause what syndrome?
Hyperprolactinemia
121
Neuroleptic agents, antidepressants, cimetidine, verapamil, opates, and marijuana can cause what syndrome?
Hyperprolactinemia
| all interfere with Dopamine
122
Which 2 organ failures can cause hyperprolactinemia from ↓ metabolism of the H?
Kidney and Liver
123
What are the 3 indications for medical treatment of a prolactinoma?
Infertility, hypogonadism, galactorrhea
124
What is the test for acromegaly?
Serum IGF-1
125
Why does a random serum level of GH not helpful in the Dx of acromegaly?
because of the pulsatile secretion of GH
126
What is teh treatment of choice for GH secreting tumors?
CUT IT OUT
127
This is the clinical syndrome produced by sudden hemorrhage or infection of the pituitary gland.
Pituitary apoplexy
128
What are teh 2 electrolyte abnormalities that can cause DI?
hyperCa
| hypoK
129
What is the plasma osmolality in pts with DI?
> 295 mOsm/kg
130
What is the plasma osmolality in pts with psychogenic polydipsia?
< 280 mOsm/kg
131
What is the urinary concentration of Na in SIADH?
> 20 mEq/L
132
What are the serum levels of creatinine and uric acid in SIADH?
normal creatinine and ↓ serum uric acid
133
Which condition causes ↑ creatinine and uric acid?
Subclinical hypovolemia
134
Waht is the physical diagnostic sign that is absent despite an expanded extracellular fluid volume in SIADH?
Edema
135
Lethargy, malaise, N/V, and confusion are signs of what problem?
Hyponatremia
136
What is the DOC for chronic SIADH?
Demeclocycline
137
What is administered IV in acute neuro sequelae are present in SIADH?
hypertonic saline
138
However, what is the main problem with rapid correction of hyponatremia?
Central pontine myelinolysis
