Adrenal Function

Question 1

Wher are the adrenal glands located?

Answer 1

The adrenal glands are located abouve the kidneys, if either adrenal gland is removed, the other will double in size.

Question 2

Name the two distinct parts of the adrenal gland

Answer 2

1) The outer cortex

2) The inner medulla

Question 3

The cortex can be further subdivided into the….

Answer 3

Outer cortex - Zona glomerulosa cells are fund here

Inner cortex - Zona fasciculata and Zona Reticularis cells are found here

Question 4

Describe the Zona Fasciculata

Answer 4

Zona Fasciculata consists of steroid hormone secreting cells that make steroid hormones.

Question 5

Describe the Zona Reticularis

Answer 5

The Zona Reticularis cells are responsible for producing androgen hormones, such as DHEA and androstenedione.

Question 6

Describe the cells found in the adrenal medulla - what hormones are found here?

Answer 6

The cells found in the adrenal medulla contain modified ganglion cells which are similar to modified nerve cells. They look completely different to the cells in the Zona Fasciculata that produce cortisol. Noradrenaline and adrenline are found here in vesicles to stimulate the sympathetic nervous system.

Question 7

Describe the histology of the cells in the adrenal glands.

Answer 7

Outer capsule

Youngest - Glomerulosa matures to form the Fasciculate matures to form the Reticularis which matures to form the modified ganglion cells in the inner medulla.

Question 8

State the intermediates when forming steroid hormones. For each intermediate, state the number of carbon atoms in each intermediate

Answer 8

Cholesterol (C27) —–> Pregnane derivatives such as progesterone, and corticoid derivatives (C21) —-> Androgens such as DHEA and androstenedione(C19) —-> Oestrogen derivatives (C18)

Question 9

Describe the role of Aldosterone (ADST). Mention the site of synthesis, classification of the hormone function and the MOA

Answer 9

Site of synthesis: Zona Glomerulosa
Classification of the hormone: Mineralocorticoid
Function: Controls the balance of electrolytes to maintain homeostasis
MOA: ADST targets renal tubules, more K+ excreted, more Na+ reabsorbed —-> more water reabsorbed ————–> Higher BP. ADST release regulated by RAAS.

Question 10

State the following about cortisol:

a) The site of synthesis
b) Classification of the hormone
c) Stimulus the body responds to
d) Effects on the body

Answer 10

A) Synthesised in the Zona Fasciculata in the Inner cortex
B) Glucocorticoid
C) Stress
D) Metabolism, cardiovascualr system and the inflammatory and immune systems.