QuestionSBA
QuestionChoice
Antidiuretic hormone (ADH) is also released upon stimulation by angiotensin II, however, it does not directly stimulate aldosterone release. ADH is released from the posterior pituitary and acts to increase water reabsorption from the collecting duct.
10003748
c
Increased ADH levels
QuestionChoice
Parathyroid hormone (PTH) levels are not increased in hypovolaemia. PTH is involved in calcium homeostasis. The most common cause of primary hyperparathyroidism is an adenoma of the parathyroid glands.
10003747
b
Increased PTH levels
QuestionChoice
Whilst increased renin levels indirectly cause increased aldosterone production via the renin-angiotensin-aldosterone system by converting angiotensinogen to angiotensin I, it is angiotensin II that directly acts on the adrenal cortex to increase aldosterone production. The question specifies that the answer should be a direct trigger.
10003750
e
Increased renin levels
QuestionChoice
Adrenocorticotropic hormone (ACTH) is released from the anterior pituitary. It stimulates the zona fasciculata of the adrenal cortex to produce glucocorticoids. Whilst increased ACTH levels have a very minimal role in increasing aldosterone secretion, decreased ACTH levels do not.
10003749
d
Decreased ACTH levels
QuestionChoice
In response to hypovolaemia, the juxtaglomerular cells of the kidney secrete renin. Renin acts to convert angiotensinogen (a hormone produced by the liver) to angiotensin I. Angiotensin I in turn is converted by angiotensin-converting enzyme (ACE) to angiotensin II. Angiotensin II acts on the zona glomerulosa of the adrenal cortex to increase aldosterone release.
10003746
a
Increased angiotensin II levels
Concept
Chapter
2693
3896
Actions of aldosterone
Topic
168
Renal Physiology
13296
A 54-year-old man is brought to the Emergency Department following a serious road traffic collision. He has lost a significant amount of blood and the major haemorrhage protocol is activated.

As part of the physiological response to hypovolaemia, the renin-angiotensin-aldosterone system is activated.

Which of the following is a direct trigger for aldosterone release?
a