hypothalamic-pituitary hormones (Exam 1)

Question 1

What is another name for the Growth Hormone?

Answer 1

Somatropin

Question 2

A child needs replacement therapy of growth hormone. Which is more effective for dosing?

A. Daily at bedtime via SC or 3 times a week IM?

Answer 2

daily at bedtime via SC- this mimics natural release pattern

Question 3

What can you use to treat children who have a growth hormone insensitivity? (laron dwarf)

Answer 3

can treat recombinant IGF-1

Question 4

What is the drug name for recombinant IGF-1?

Answer 4

Mecasermin-Increlex

Question 5

What should pts due before injecting recombinant IGF-1?

Answer 5

Eat some carbs before injection because there is a concern for hypoglycemia

Question 6

What is the most common causes of growth hormone deficiency?

Answer 6

usually due to pituitary tumor or consequences of its treatment- (surgery/radiation )

Question 7

What increases the release of growth hormone?

Answer 7

the release is increased by GHRH

Question 8

What decreases the release of growth hormone?

Answer 8

somatostatin also paradoxically decreased by dopamine agonists in acromegaly

Question 9

limited studies of Illicit use of growth hormone in the elderly for anti-aging suggest what?

Answer 9

That it is associated with small changes in body composition and INCREASED rates of adverse effects (edema, joint pain, muscle pain, carpal tunnel

Question 10

True or false can your recommend growth hormone to the elderly for anti aging?

Answer 10

False it can not be recommended

Question 11

What side effects can occur with the use of somatropin?

Answer 11

1. insulin resistance and glucose intolerance may occur
2. Slight increased risk for idiopathic intracranial hypertension
3. Rarely pancreatitis, gynecomastia, nevus growth

Question 12

What is somatostatin?

Answer 12

This is a growth hormone- inhibiting hormone can also be called Somatotropin release-inhibiting factor

Question 13

Where is somatostatin present in the body?

Answer 13

it is in the…

1. hypothalamus
2. nervous system
3. gut
4. endocrine and exocrine glands

Question 14

True or false: Somatostatin inhibits GH release via GPCR coupled to Gi decreasing cAMP levels and activating K+ channels

Answer 14

True

Question 15

True or false Beetches: somatostatin INCREASES secretion of gastric enzymes and acid- INCREASED GI motility- STIMULATES the release of serotonin

Answer 15

False. The bolded words should be

1. decrease
2. decreased
3. suppresses

Question 16

True or false: Somatostatin reduces insulin and glucagon release

Answer 16

True

Question 17

Does somatostatin interfere with TRH ability to release TSH

Answer 17

yes it does

Question 18

What is the half life of somatostatin following exogenous administration?

Answer 18

it is only 3-4 min which limits its therapeutic effects

Question 19

What organ system has a major role in the clearance of somatostatin?

Answer 19

The kid knees

Question 20

What are the names of two other meds that are similar to somatostatin?

Answer 20

Octreotide and Lanreotide

Question 21

What is the half life of Octreotide in the plasma? how long does it last? How often is it given and by what method?

Answer 21

1. plasma half life 90min
2. duration 12 hours
3. Given SC every 6-12 hours

Question 22

How else can Octreotide be given and how often?

Answer 22

can be IM and every 4 weeks

Question 23

How is Lanreotide administered and how often?

Answer 23

SC and every 4 weeks

Question 24

What is Octreotide and Lanreotide used for?

Answer 24

1. Pituitary or excess of growth hormone

2. control of bleeding from esophageal varices and GI hemorrhage

Question 25

What are two conditions associated with pituitary excess where Lanreotide and Octreotide can be used?

Answer 25

1. Acromegaly and gigantism

Question 26

What treatment is preferred for when the pituitary releases excess growth hormone?

Answer 26

Surgical resection- unless adenoma does not appear fully resectable

Question 27

After a response is seen with the use of SC Octreotide, what med is utilized next

Answer 27

Long acting somatostatin analog

Question 28

Are dopamine agonists as effective as SST (somatostatin) analogs?

Answer 28

no they are not; however Cabergoline is a preferred agent for adjunctive management of acromegaly with advantage of oral administration

Question 29

What is Pegvisomant (somavert)?

Answer 29

- this is a GH receptor antagonist - It binds to receptors blocking GH access, but does not activate signaling transduction - administered single dose SC

Question 30

true or false: SST analogs can be used for WDHA (watery diarrhea, hypokalemia, achlorhydria)

Answer 30

True

Question 31

What is a side effect of SST drugs?

Answer 31

- transient hyperglycemia | - cardiac effects (brady and conduction disturbances)

Question 32

what is prolactin release under control of?

Answer 32

under inhibitory control by hypothalamic dopamine at D2 receptors

Question 33

what is the main stimulus for the release of prolactin?

Answer 33

suckling causes 10-100 fold increase

Question 34

If there are sufficient levels of, insulin, estrogen, progestin, and corticosteroids what will prolactin stimulate?

Answer 34

milk production

Question 35

Prolactin stimulates milk production, what else does it stimulate?

Answer 35

Proliferation and differentiation of mammary tissue during pregnancy?

Question 36

So what does prolactin inhibit?

Answer 36

inhibits gonadotropin (FSH/LH) release and or ovarian response to these hormones

Question 37

What two drugs are used for prolactin issues?

Answer 37

Cabergoline and bromocriptine

Question 38

Is there any treatment available for prolactin deficiency?

Answer 38

no there isn't

Question 39

why are prolactinomas that cause hyperprolactinemia amenable to pharmacotherapy?

Answer 39

this is because of the availability of dopamine agonists that both decrease secretion and reduces tumor size.

Question 40

What are some frequent side effects of bromocriptine?

Answer 40

nausea, vomiting, headache, postural hypotension

Question 41

Does bromocriptine activate D1 receptors?

Answer 41

yes

Question 42

What is the preferred agent for hyperprolactinemia?

Answer 42

Cabergoline

Question 43

which is more selective for D2 receptors? and more effective in reducing prolactin secretion?

Answer 43

cabergoline

Question 44

which is better tolerated? cabergoline or bromocriptine?

Answer 44

cabergoline

Question 45

What is another name for vasopressin?

Answer 45

it is the antidiuretic hormone, ADH

Question 46

what is the half life of vasopressin?

Answer 46

about 20 minutes

Question 47

Which one is more stable desmopressinor vasopressin?

Answer 47

desmopressin, it has a half life of 1.5-2.5 hours

Question 48

What part of the kidney does desmo and vasopressin act on?

Answer 48

the collecting tubules

Question 49

What are the stimuli in the body that cause the release of vasopressin?

Answer 49

1. main stimuli is rising blood osmolarity | 2. decrease circulating blood volume

Question 50

True or false: alcohol can inhibit the release of ADH

Answer 50

true

Question 51

What receptors mediate the renal actions of ADH?

Answer 51

V2 receptors

Question 52

What are the non-renal actions of ADH?

Answer 52

release of coagulation factor VIII and von willebrands factor

Question 53

Other than the V2 receptors what other receptors does ADH-vasopressin act on?

Answer 53

V1 receptors

Question 54

What is the effect of ADH on V1 receptors?

Answer 54

- mediates vasoconstriction of vascular smooth muscle | - BUT pressor responses only at much higher concentrations than for maximal antidiuresis

Question 55

Central diabetes insipidus is a posterior pituitary disease resulting in hypofunction. what two medications can be used to treat it?

Answer 55

1. Desmopressin | 2. Chlorpropamide

Question 56

What is central diabetes insipidus?

Answer 56

this is when you have inadequate ADH secretion from the posterior pituitary

Question 57

Which of the two is the treatment of choice for central diabetes insipidus? why? A. Desmopressin B. Chlorpropamide

Answer 57

A. Desmopressin because it is highly selective for V2 receptor with little vasopressor or uterotonic actions

Question 58

Can desmopressin be given nasally?

Answer 58

Yes and an adverse reaction can be nasal irritation.

Question 59

When taken orally what can be some adverse reactions?

Answer 59

1. Mild elevation of liver enzymes 2. asthenia 3. water intoxication, 4. abdominal cramps

Question 60

What 2 drugs can induce nephrogenic diabetes insipidus?

Answer 60

1. Lithium. This drug reduces V2-receptor mediated stimulation of adenyl cyclase 2. Demeclocycline- possibly acts via block of ADH binding to receptor

Question 61

What is one treatment for nephrogenic diabetes insipidus that doesnt seem to make sense?

Answer 61

The use of thiazide diuretics

Question 62

How does the use of thiazide diuretics work for nephrogenic diabetes insipidus?

Answer 62

Paradoxically reduce the polyuria of patients. -somehow antidiuretic effect parallels ability to cause natriuresis

Question 63

Other than the use of thiazide diuretics for nephrogenic diabetes insipidus what other drug can you use?

Answer 63

NSAIDS

Question 64

how do NSAIDS work for nephrogenic diabetes insipidus?

Answer 64

Prostaglandins attenuate ADH-induced antidiuresis so INHIBITION of PG synthesis by indomethacin may relate to the antidiuretic response. -INDOMETHACIN HAS GREATEST EFFICACY AMONG NSAIDS

Question 65

What combined therapy can be used for treatment of nephrogenic diabetes insipidus?

Answer 65

Thiazide and indomethacin

Question 66

We have talked about hypofunction of posterior pituitary. What is a condition of hyperfunction of posterior pituitary?

Answer 66

SIADH

Question 67

What disorders can cause SIADH?

Answer 67

1. Malignancies 2. Pulmonary disease 3. CNS trauma, infections, tumor

Question 68

What drug classes most commonly implicated can lead to life threatening hyponatremia and then seizures?

Answer 68

1. Psychotropic agents: SSRIs, haloperidol, tricyclic antidepressant 2. Sulfonylureas (chlorpropamide) 3. Vinca alkaloids chemotherapy 4. Methylenedioxy methamphetamine (MDMA)

Question 69

what is the initial conservative approach for treatment of hyponatremia?

Answer 69

initially just restriction of free water intake

Question 70

What drug inhibits ADH effect on distal tubule and has been the preferred drug in patients with inadequate response to conservative therapy for Hyponatremia?

Answer 70

Demeclocyline

Question 71

What two drugs are V2 receptor antagonists and have been used for hyponatremia?

Answer 71

1. Tolvaptan | 2. Conivaptan

Question 72

If severe symptomatic hyponatremia is present, what can be given along with conivaptan?

Answer 72

hypertonic saline 3% which permits a more rapid correction

Question 73

If there is a to rapid correction of hyponatremia what can occur?

Answer 73

cerebellar pontine myelinolysis

Question 74

Vasopressin is a V1 receptor mediated drug. Can it be used for bleeding in esophageal varices? is there another option that is better tolerated and preferred?

Answer 74

1. Vasopressin can be used | 2. The better option is octreotide

Question 75

True or false: Vasopressin can be used for severe septic shock and formerly used for shock-refactory ventricular tachycardia?

Answer 75

True

Question 76

Which medication is V2 receptor mediated and can be used for nocturnal enuresis?

Answer 76

Desmopressin

Question 77

What two blood conditions can desmopressin be used for?

Answer 77

1. Von willebrands disease | 2. Moderate hemophilia A (elevates factor VIII)