2-2-16-Hypothalamic-Pituitary Relationships (Lopez) Flashcards Preview

Endocrine > 2-2-16-Hypothalamic-Pituitary Relationships (Lopez) > Flashcards

Flashcards in 2-2-16-Hypothalamic-Pituitary Relationships (Lopez) Deck (46):
1

The relationship between the hypothalamus and the anterior pituitary is ___

The relationship between the hypothalamus and the posterior pituitary is ___

Both neural and hormonal

Neural

2

The anterior pituitary is connected to the hypothalamus by ___

Hypothalamic-hypophysial portal vessels

3

The ___ provide most of the blood supply to the anterior pituitary

hypothalamic-hypophysial portal vessels

4

___ is when you have low or high levels of hormone due to a defect in the peripheral endocrine gland (i.e., thyroid gland)

Primary endocrine disorder

5

___ is when you have low or high levels of hormone due to a defect in the pituitary gland

Secondary endocrine disorder

6

____ is when you have low or high levels of hormone due to a defect in the hypothalamus

Tertiary endocrine disorder

7

In the anterior pituitary,

___ releases ACTH
___ releases TSH
___ releases FSH and LH
___ release GH
___ releases prolactin

Corticotroph=ACTH
Thyrotroph=TSH
Gonadotroph=FSH and LH
Somatotroph=GH
Lactotroph=Prolactin

8

List the hypothalamic releasing hormone for the secretion of:

a-TSH
B-ACTH
C-LH, FSH
D-GH
E-Prolactin

A-TRH
B-CRH
C-GnRH
D-GHRH
E-PIF (dopamine) or TRH (elevated)

9

The anterior lobe hormones can be separated into these organizational families based on structural and functional homology

-ACTH family
-TSH, FSH, and LH family
-GH and prolactin family

10

___ has melanocyte-stimulating hormone activity

ACTH

11

In ___ disease, ACTH levels increase and skin pigmentation is a symptom of this disorder

Addison

12

ACTH stimulates these 2 zones of the adrenal gland:

Medulla and Cortex

13

The actions from GH result from 2 different effects:

___ has an effect on the target tissues (e.g., skeletal m., liver, adipose)

__ is mediated by the production of somatomedins in the liver (e.g., IGF-1)

Direct

Indirect

14

This particular action/effect from GH causes an increase in [blood glucose] which can cause insulin resistance, decreased glucose uptake and utilization by target tissue, increased lipolysis in adipose. The result is an increase in blood insulin levels.

Diabetogenic effect

15

This particular action of GH leads to an increased uptake of AA's, stimulation of synthesis of DNA, RNA, and protein, and is mediated by somatomedins.

Increased protein synthesis and organ growth

16

This particular action of GH stimulates synthesis of DNA, RNA, protein, is mediated by somatomedins, and increases metabolism in cartilage-forming cells and chondrocyte prolfieration

Increased linear growth

17

Acromegaly can be a result of what?

GH excess

GH excess is mostly due to a GH-secreting pituitary adenoma

18

What happens if you have GH excess before puberty?

What happens if you have GH excess after puberty?

Gigantism

Increased periosteal bone growth, increased organ size, increased extremities size, coarsening of facial features, insulin resistance, and glucose intolerance

19

___ supports the actions of estrogen and progesterone

Prolactin

20

List 3 actions of prolactin:

Breast development: at puberty --> stimulate proliferation and branching of mammary ducts; during pregnancy --> stimulate growth and development of the mammary alveoli

Lactogenesis--> induce synthesis of lactose, casein, and lipids

Suppression of ovulation --> inhibits synthesis and secretion of GnRH

21

___ is a condition of inadequate or absent production of the anterior pituitary hormones.

Panhypopituitarism

22

What are some causes of hypopituitarism?

Brain damage--> traumatic brain injury, subarachnoid hemorrhage, irradiation, stroke

Pituitary tumors--> adenomas

Non-pituitary tumors--> cranipharyngioma: most common tumor affecting the HP axis in children

Infections--> meningitis, encephalitis, hypophysitis

Infarction--> sheehan syndrome: pituitary in pregancy is enlarged and more vulnerable to infarction

Autoimmune disorders, pituitary hypoplasia or aplasia, genetic or idiopathic causes

23

___ syndrome is when the pituitary gland is enlarged and more vulnerable to infarction during pregnancy

Sheehan

24

Most pituitary tumors are ___ and occur spontaneously

pituitary adenomas

25

___ adenomas release an active hormone in excessive amounts into the bloodstream. The pt usually experience symptoms related to the hormone action in the body

Hormone-producing pituitary

26

A prolactinoma is a tumor that overproduces prolactin and is associated with ____

Hypogonadism and galactorrhea

27

Acromegaly and gigantism are caused by an excess of ___

GH

28

___ is caused by a pituitary tumor stimulating an overproduction of cortisol

Cushings disease

29

The precursor peptide of ADH is ___

The precursor peptide of Oxytocin is ___

Preprossophysin

Prepro-oxyphysin

30

___ is the major hormone concerned with the regulation of body fluid

ADH

Prepropressophysin to Propressophysin in the hypothalamus --> Goes down hypothalamic-hypophyseal tract (axons of neurons) to the posterior pituitary --> ADH in the posterior pituitary --> when needed, ADH into the bloodstream --> target tissues of kidneys and blood vessel

31

What are triggers of ADH secretion?

-Decreased BP --> cardiac and aortic baroreceptors --> sensory neuron to hypothalamus

-Decreased arterial stretch due to low blood volume --> atrial stretch receptors --> sensory neuron to hypothalamus

-Increased osmolarity --> hypothalamic osmoreceptors --> interneuron to hypothalamus

These all act on hypothalamic neurons that synthesize ADH --> ADH released from posterior pituitary

32

Secretion of ADH is most sensitive to ___ changes. An increased of only 1% of this factor will increased ADH secretion

Osmolarity

33

Aquaporin-2 channels can be found on the ___ membrane and Aquaporin-3 channels can be found on the ___ membrane

Aq2=Apical

Aq3=Basolateral

34

Too little water will result in ___ levels of ADH in the bloodstream

Too much water will result in ___ levels of ADH in the bloodstream

Increased

Decreased

35

When the hypothalamus detects too little water, the pituitary gland releases ADH, the kidneys remove less water from the blood and the urine becomes ___

More concentrated

Will also increase thirst levels as plasma [ADH] exceed ~295 mOsm

36

WHen the hypothalamus detects too much water in the blood, the pituitary gland releases less ADH, the kidneys remove more water from blood and the urine becomes ____

More dilute

37

___ is characterized by a lack of an effect of ADH on the renal CD which causes frequent urination and a large volume of dilute urine

Diabetes Insipidus

38

___ results from damage to the pituitary and destruction of the hypothalamus that leads to a lack of or decrease in plasma ADH

Central DI

39

___ is caused by drugs such as lithium or chronic disorders such as polycystic kidney disease and sickle cell anemia. The kidneys are unable to respond to ADH (Increased plasma ADH)

Nephrogenic DI

40

Desmopressin can be used to treat ___ DI

Central DI--> Desmopressin does not work for Nephrogenic DI

Desmopressin prevents water excretion

41

Plasma ADH levels are expected to be lower than normal in ___

Plasma ADH levels are expected to be higher than normal in ___

Central DI

Nephrogenic DI

42

___ is characterized by excessed ADH secretion, excessive water retention, and/or hypoosmolarity fails to inhibit ADH release

SIADH

43

How do you treat SIADH?

Fluid restriction
IV hypertonic saline
V2 receptor antagonist
Demeclocycline

44

Predict anatomic/physiologic changes as a result of pituitary failure and the following hormones:
A-GH
B-FSH/LH
C-TSH
D-ACTH
E-ADH

A-Children: short stature, Adults: no effect
B-Infertility, hypogonadism, reduced sperm count in men; Menstrual irregularity in women
C-Hypothyroidism
D-Loss of pigmentation, hypoadrenalism
E-Diabetes insipidus

45

___ is a collection of axons whose cell bodies are located in the hypothalamus

Posterior pituitary --> secretes neuropeptides
-Supraoptic nucleus (primarily ADH)
-Paraventricular nucleus (primarily oxytocin)

46

SIADH is characterized by ___

Euvolaemia --> Total body water is increased but normal total body sodium