CLINICAL CHEMISTRY 3 ENDOCRINOLOGY: HYPOTHALAMIC AND PITUITARY FUNCTION

Question 1

It is a portion of the brain located in the walls and floor of third ventricle, it serves as the link between the nervous system and endocrine system

Answer 1

HYPOTHALAMUS

Question 2

It is responsible for producing melatonin and is dubbed as “third eye”

Answer 2

PINEAL GLAND

Question 3

This substance is increased at night and decreases the pigmentation of the skin

Answer 3

MELATONIN

Question 4

It is also known as the hypophysis , a small egg-shaped gland located at the base of the brain beneath the hypothalamus

Answer 4

PITUITARY GLAND

Question 5

3 lobes of the Pituitary Gland

Answer 5

Anterior- Adenohypophysis or Pars Tuberalis
Intermediate- Pars Intermedialis
Posterior- Neurohypophysis or Pars Distalis

Question 6

5 Types of cells by Immunological Tests

Answer 6

Somatotroph – secretes GH
Lactotrophs – secretes Prolactin/Mammotrophs
Thyrotroph – secretes TSH
Gonadotroph – secretes α and β subunits of FSH & LH
Corticotroph – secretes Proopiomelanocortin

Question 7

It is considered as an amphibolic hormone that directly antagonizes the effect of insulin in glucose metabolism.

Answer 7

GROWTH HORMONE/Somatotropin

Question 8

Factors that affects GH STIMULATION SECRETION

Answer 8

Sleep
Exercise
Physiologic stress
Amino acids
Hypoglycemia
Sex steroids (estradiol)
a-Agonists (norepinephrine)
b-blockers (propranolol)

Question 9

Factors that affects GH INHIBIT SECRETION

Answer 9

Glucose loading
b-Agonists (epinephrine)
a-Blockers (phentolamine)
Emotional or Psychogenic stress
Nutritional deficiencies
Insulin deficiency
Thyroxine deficiency

Question 10

A pituitary lactogenic hormone which is important for childbirth or labor

Highest level 4-8am and 8-10pm

Answer 10

PROLACTIN

Question 11

Main inhibitor of Prolactin

Answer 11

DOPAMINE

Question 12

Another name for TSH

Answer 12

Thyrotropin

Question 13

Important markers for diagnosing fertility and menstrual cycle disorders

Answer 13

FSH and LH
Follicle Stimulating Hormone- follicle growth and spermatogenesis
Luteinizing hormone- ovulation and testosterone production

Question 14

It is a hormone that acts by stimulating the growth and secretion of corticosteroids, elevated during time of stress

Answer 14

ADRENOCORTICOTROPIC HORMONE
ACTH

Question 15

Regulator of adrenal androgen synthesis

Answer 15

CORTISOL

Question 16

ACTH deficiency could lead to atrophy of what zona?

Answer 16

Zona glomerulosa and Zona reticularis

Question 17

Other name for Posterior Pituitary Gland

Answer 17

NEUROHYPOPHYSIS

Question 18

It stimulates smooth muscle contraction especially in uterus at term of birth also known as the “Fergusson reflex”

Answer 18

OXYTOCIN

Question 19

Oxytocin promotes the secretion of what substance?

Answer 19

PROSTAGLANDIN

Question 20

Diagnostic test for Arginine Vasopressin

Answer 20

Overnight water deprivation test
8-12 hrs no fluid intake
should not rise above 300mOsm/kg

Question 21

What clotting factor is released upon secretion of Arginine Vasopressin

Answer 21

Clotting Factor VII

Question 22

This substance promotes the secretion of ADH, and is responsible for the maintenance of blood volume, pressure and tonicity

Answer 22

ARGININE VASOPRESSIN

Question 23

It is a disease which has a hyposecretion of Growth Hormones

Answer 23

Dwarfism

Question 24

Types of Dwarfism

Answer 24

Achondroplasia- prevents changing from cartilage to bone
Hypochondroplasia- short-limbed dwarfism
Spondyloepiphyseal Dysplasia- primary involvement of the vertebrae and epiphyseal centers
Diastrophic dysplasia- onset joint pain and deformity

Question 25

Gold standard test for Growth Hormone deficiency

Answer 25

INSULIN TOLERANCE TEST
fasting serum and complete rest before blood collection

Question 26

A potent GH stimulant that is given for the GH Stimulation test

Answer 26

CLONIDINE

Question 27

Second confirmatory test for GH deficiency

Answer 27

Arginine Stimulation Test
>5 ng/ml adults
>10 ng/ml children
Failure to rise is ABNORMAL

Question 28

A Growth Hormone defect which is characterized by excess production of GH hormone

Answer 28

Gigantism- childhood onset
Acromegaly- adults

Question 29

Screening test for Acromegaly

Answer 29

SOMATOMEDIN C TEST/INSULIN_LIKE GROWTH FACTOR 1
Increase IGF-1- Indicator for Acromegaly
Decrease IGF-1 Indicator for GH deficiency

Question 30

Confirmatory test for Acromegaly

Answer 30

OGTT/Glucose suppression test
Hyperglycemia should suppress GH to <1 ug/L
Failure to decline for atleast >2 ug/L may indicate Acromegaly

Question 31

Inappropriate production of breast milk/hyperprolactinemia due to the hypersecretion of PRL

Answer 31

GALACTORRHEA

Question 32

Absence of menstrual cycle in females due to the hypersecretion of PRL

Answer 32

AMENORRHEA

Question 33

Inability to attain penile erection due to the hypersecretion of PRL

Answer 33

IMPOTENCE

Question 34

Deficiency in FSH and LH in both male and female

Answer 34

INFERTILITY

Question 35

It is a disease described as the hypersecretion of ACTH and is the main cause of Obesity

Answer 35

CUSHING’S DISEASE

Question 36

It is the hyposecretion of glucocorticoids and aldosterone, or the deficiency in ACTH hormone

Answer 36

ADDISON’S DISEASE

Question 37

Deficiency in ADH hormone resulting in severe polyuria (less than 3L of urine/day)

Answer 37

DIABETES INSIPIDUS

Question 38

A type of DI which is deficient in ADH with normal ADH receptor

Answer 38

TRUE DIABETES INSIPIDUS

Question 39

A type of DI which has a normal ADH with normal ADH receptor

Answer 39

NEPHROGENIC DIABETES INSIPIDUS

Question 40

Water load test is used for the diagnosis of what disease?

Answer 40

Syndrome of Inappropriate ADH secretion

Question 41

It is the failure of either the pituitary or
hypothalamus to release/secrete the hormones,
resulting to a loss of anterior pituitary function.

Answer 41

PANHYPOPITUITARISM