Written Prep - Endo

Question 1

Anterior Pituitary:

Blood supply is from where?

Answer 1

Blood supply from hypothalamic-pituitary portal plexus via SUPERIOR HYPOPHYSIAL ARTERY

Question 2

Anterior Pituitary:

Anterior pituitary hormone subunits

Answer 2

Alpha subunit is common to: TSH, LH, FSH and hCG

Beta subunit determines specificity

Question 3

Growth hormone:

Secretion

Answer 3

GH is secreted by SOMATOTROPHS

In response to GHRH

Question 4

Growth Hormone:
Stimulation of GH Secretion
&
Inhibition of GH Secretion

Answer 4

Stim by: ghrelin and estrogen

Inh by: IGF-1, Somatostatin and Chronic glucocorticoids

Question 5

Growth Hormone:

When will you find elevated and decreased levels of GH?

Answer 5

Elevated GH:

• Deep sleep
• Exercise and physical stress
• Trauma and sepsis

Decreased GH:
- obesity

Question 6

Action of Growth Hormone: Indirect and Direct Actions

Answer 6

INDIRECT ACTION:
GH stimulates IGF-1 release from liver

IGF-1 then acts in skeletal muscle and cartilage, increases uptake of amino acids and protein synthesis

DIRECT ACTION:

• In epithelium and connective tissue: stimulates MITOSIS
• In adipose tissue stimulates BREAKDOWN OF FATTY ACIDS
• In liver stimulates GLYCOGENOLYSIS