Test your understanding of neuroendocrinology with eight more fact-based and applied questions about the hypothalamic-pituitary axes.
Reviewed by: awaiting review
Congratulations - you have completed Neuroendocrinology II. You scored %%SCORE%% out of %%TOTAL%%. Your performance has been rated as %%RATING%%
Your answers are highlighted below.
Hypophysectomy (the surgical removal of the pituitary gland) is usually conducted through which sinus?
Question 1 Explanation:
The pituitary gland is found behind the sphenoid sinus. Surgical removal of the pituitary gland (hypophysectomy) is frequently done trans-sphenoidally. The sella turcica, aka the hypophyseal fossa, is the cavity within the skull where the pituitary gland sits but it is not a sinus.
Which of the following hormones is not secreted from the anterior pituitary gland:
Which of the following hormones is not produced by the hypothalamus?
Question 3 Explanation:
Vasopressin and oxytocin are released from the posterior pituitary gland but synthesised in the hypothalamus. Prolactin is released from the anterior pituitary gland but its production is inhibited by dopamine, which is secreted by the hypothalamus (sometimes referred to as the tubero-hypophyseal dopamine pathway).
What best describes the hypophyseal portal system?
The pathway taken by dopamine to inhibit prolactin secretion
Venous blood flow between the hypothalamus and anterior pituitary gland
The layout of tissues connecting the hypothalamus with the posterior pituitary gland
An alternative name for the pituitary stalk
Magnocellular axons running from the hypothalamus to the anterior pituitary gland
Question 4 Explanation:
The hypothalamus sends hormones to the anterior pituitary gland via a vein that runs through the pituitary stalk. A portal system is where venous blood flows from one capillary bed to a second capillary bed.
Which two of the following hormones are most likely to be responsible for an increase in blood glucose levels?
Question 5 Explanation:
GHRH stimulates the production of hGH (human growth hormone). The body needs glucose to grow therefore hGH stimulates glucose secretion. ACTH stimulates corticosteroid release, one of the effects of which is an increase in blood glucose; in fact, corticosteroid therapy can increase blood glucose so is an important side effect to look out for, especially in diabetics. TSH would stimulate the production of thyroid hormones that increase metabolic activity in cells and therefore draw more glucose in from the blood stream; in fact hypothyroidism can cause diabetes in some patients. Insulin is released in response to high blood glucose, and ADH has no role in glucose regulation at all.
A psychiatrist is speaking to one of her in-patients, a 33 year old male. He is complaining of leaking from his nipples since being started on a new drug. Which of the following drugs is most likely to be responsible?
Question 6 Explanation:
Risperidone is a classical antipsychotic and inhibits the effects of dopamine. Dopamine inhibits prolactin secretion, therefore the patient will have higher circulating levels of prolactin which has caused galactorrhoea.
A patient presents to their GP complaining of weight gain and bruising. The GP notices the patient has florid cheeks and a round face and, on examination, spots stretch marks on their abdomen. They are on no medication and have no relevant medical history. Which of the following hormones is likely to be raised?
Question 7 Explanation:
These are symptoms of Cushing’s syndome which is caused by an increase of cortisol from the adrenal cortex. Cortisol secretion is regulated by ACTH (adrenocorticotrophic hormone). Therefore it is this hormone that is most likely to be raised. A raised TSH (and low T4) might be expected if the patient had hypothyroidism, but this would mainly account for their weight gain, not their other symptoms.
A 45 year old patient is referred to the endocrinology clinic by his GP. The patient says his wedding ring is now too small for his fingers and over the last year his shoe size has gone up as well. An MRI scan reveals an enlarged pituitary gland. Which hormone is likely responsible for the man’s presentation?
Question 8 Explanation:
This patient has acromegaly secondary to a pituitary adenoma. A change in shoe or glove size is a characteristic symptom of this syndrome. It is caused by human growth hormone (hGH). As this is a pituitary problem, a rise in GHRH would not be responsible for this patient’s presentation, even though it stimulates hGH secretion.
Once you are finished, click the button below. Any items you have not completed will be marked incorrect.
There are 8 questions to complete.