Pituitary Glands

Question 1

According to FSH and LH

there are two types of disorder in releasing of these hormones.

Answer 1

1-Primary –> the deFect on testes

2. Secondary —> defect on anterior Pituitary that lead tp decrease of production pf LH&FSH

Question 2

Whats considered as Posterior Feedback Mechanism

Answer 2

So body sends signals for hypothalmus to produce LHRH &FSRH

Question 3

Negative Feedback Mechanism

Example + moa

Answer 3

Thyroxine
if its level is high in body —>body gives signal for pituitary to decrease corticatropin hormone production
But if there’s an tumor in pituitary this may lead to increase in production of thyroxine hormone, then increase both T4 and T3 level, then there’s a problem

Question 4

Increase in production due to hypersensitivity to other hormones like

Answer 4

if there’s B hypersensitivity, to TSH —>The production f T4 will increase as we can see in Thyrotoxicosis disease.

Question 5

Growth Hormone (Somatotropin)
prevalence

Answer 5

GH increase highly in the adolscence period and may be absent neonatal and adult period.

Question 6

Note: Increase in GH may lead to DM - explain

Answer 6

One to increase the insulin resistance and hypoglycemic effect when patient taking carbohydrates

Question 7

Growth hormone excess lead to

Answer 7

Acromegally –> insidious cosymptomatic disorder

Question 8

What occurs during Benign pituitary Tumor

Answer 8

In Benign pituitary Tumor there is an increase in size of production cells of gonadtropins which are gonadotrophes cells which finally lead to increase in GH production

Question 9

When does Acromegaly Occur?

Answer 9

Acromegaly usually occurs after fusion of epiphysis (growth plate) of the long bones

Question 10

Whats the difference between Acromegaly and Gigantism?

Answer 10

Gigantism occurs before epiphysis (epiphysis closure) - then theres an increase in height, length of arms, legs to abnormal level.

Question 11

IGF-I location and whats it stimulated by

Answer 11

IGF-I produced in the liver and t’s production is stimulated by the GIT

Question 12

What’s IGF-I ?

Answer 12

IGF-I is the hormone that goes to body organs ( heart, bone, etc.) and act as a function of GIT.

Question 13

GH can also be increased by stress

Answer 13

True

Question 14

Diagnosis of Acromegaly

Answer 14

MRI and CT scan

Question 15

Goal of Management for Acromegaly

Answer 15

1- Normalize biochemical marker ( blood sugar level which increases with GH increase, cholesterol, etc.)
2- Reduce tumor size ( as in edema)
3- keep normal pituitary function, improve clinical function
4-Decrease in mortality rate, morbidities

Question 16

Acromegaly associated with high mortality , why?

Answer 16

This may be due to its enlargemnt of heart and other agents or vessels

Question 17

Treatment for Acromegaly

When surgery is impossible

Answer 17

1- Somatostatin–>hormone that go to the hypothalmus and prevent GHRH
2- Dopamine act inversely with GH- Dopamine Antagonists
*Surgery - removing a part of pituitary gland- patients may suffer from hypopituitarism.
3- Dopamin Agonists ( Cabergoline=dostinex)
4- GH receptor Antagonists
5-Radiation Therapy ( radiation=Hypothyroidism

Question 18

For patients with increase in both GH & Prolactin, the treatment is

Answer 18

by Bromocriptine or Carbegoline can be beneficial for Acromegaly.

Question 19

Laboratory test- according to MRI and CT scan

Answer 19

1) Patient older than 1 year (x-ray: left wrist and hand)

2) Patient younger than 1 year( x-ray: knee and ankle)

Question 20

If there’s an increase in prolactin level

Answer 20

Hyperprolactinemia

Question 21

Anti-dopamine

Answer 21

can increase prolactin like domperidone

Question 22

Pathophysiology of Hyperprolactinemia

Answer 22

High level of prolactin –> Inhibition of GnRh
During breast feeding, prolactin level will increase –>inhibition of of GnRh —>decrease both LH &FSH= No ovulation or spermatogenesis.

Question 23

Prolactin Treatment

Answer 23

1- Normalize prlactin level, because like we said prolactin is toxic for GnH, also it can cause skin problems, uscle and others.

Question 24

Primary vs Secondary

Answer 24

Primary- defect in primary target organ

Secondary- defect in pituitary gland

Question 25

Acromegaly

Answer 25

GH excess

Question 26

when do we give somatostatin analogues

Answer 26

when surgery and radiation failed

s/e: gallstone, biliary slude

Question 27

Example of GH receptor antagonist

Answer 27

peg visomant coinly genetic engineering GH antagonist

Question 28

why pegvisomant increase GH, while it block its receptor

Answer 28

by declining IGF-I levels

Question 29

Dopamine Agonist examples

Answer 29

Bromocriptine, gabergoline

indications- Mildly elevated IGF-1 level, GH - prolctin co secreted tumor

Question 30

problems with radiation therapy

Answer 30

Hypopituitarism

Question 31

GH deficiency

Answer 31

During childhood

Question 32

GH Deficiency may be due to

Answer 32

Methoxamine, Isoproterenol, Glucorticoids, cimidine, Methylphendate, Amphetamine

Question 33

Clinical Diagnosis of GH deficiency

Answer 33

1- Decrease in Growth Velocity
2- Short Stature also may be present
3- Abdominal obesity
4-Prominence for the forehead 
5- Immaturity of the face

Question 34

Lab Tests in child

Answer 34

1. Gh stimulation test
2. decrease IGF-1 and IGF3
3. hypoglycemia, hypothyroidism
4. CT,MRI
5. x-RAY LEFT CHEST, hand for child younger than 1 year
   for knee , ankle for child older than 1 year

Question 35

Lab test for Adult

Answer 35

1- GH Stimulation
2- IGF-1 
3. Increase in lipid profile 
4. decrease in bonedensity 
5. Insulin resistance increase 
6Loss of other pituitary hormone