Oxytocin and antidiuretic hormone (ADH; vasopressin) are:
- A. complex steroids.
- B. synthesized and stored in the posterior pituitary.
- C. released from the anterior pituitary where blood is hypotonic.
- D. synthesized in the hypothalamus and released from the posterior pituitary.
Correct Answer: D
Rationale: Oxytocin and antidiuretic hormone (ADH; vasopressin) are both synthesized in the hypothalamus, specifically in the supraoptic and paraventricular nuclei. After synthesis, they are transported along axons to the posterior pituitary where they are stored until they are released into the bloodstream when needed. This is why they are released from the posterior pituitary, not the anterior pituitary. These hormones have different functions in the body, with oxytocin being involved in labor and breastfeeding, while ADH plays a role in regulating water balance and blood pressure.
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Sheehan's syndrome presents with:
- A. Cardiac failure
- B. Persistent lactation
- C. Fever
- D. Striking cachexia
Correct Answer: B
Rationale: Sheehan's syndrome, also known as postpartum hypopituitarism, is a condition characterized by pituitary gland dysfunction due to severe blood loss during childbirth, resulting in ischemic necrosis of the pituitary gland. As a consequence of pituitary hormone deficiency, one of the hallmark manifestations of Sheehan's syndrome is persistent lactation despite stopping breastfeeding. This occurs due to inadequate prolactin inhibition, leading to continuous milk production. Other common symptoms of Sheehan's syndrome include fatigue, weight loss, menstrual irregularities, hypothyroidism, adrenal insufficiency, and other pituitary hormone deficiencies. Cardiac failure, fever, and striking cachexia are not typical presentations associated with Sheehan's syndrome.
What is the most common cause for the overproduction of growth hormone in acromegaly?
- A. Hypothalamic lesion
- B. Hyperplasia of the pituitary stalk
- C. Pituitary lesion
- D. Pituitary adenoma
Correct Answer: D
Rationale: Acromegaly is typically caused by the overproduction of growth hormone (GH) by the pituitary gland. In around 95% of cases, this overproduction is due to the presence of a non-cancerous tumor called a pituitary adenoma. These adenomas are benign, slow-growing tumors that cause the pituitary gland to produce excessive amounts of growth hormone, leading to the characteristic symptoms of acromegaly such as enlargement of the bones and soft tissues.
Which of the following is not a recognized feature of myxoedema?
- A. Ascites
- B. Cerebellar ataxia
- C. Increased incidence of pernicious anaemia
- D. Thyroid acropachy
Correct Answer: D
Rationale: Myxoedema is a severe form of hypothyroidism characterized by a range of symptoms and signs. Ascites, cerebellar ataxia, and increased incidence of pernicious anaemia are recognized features of myxoedema. However, thyroid acropachy is not a recognized feature of myxoedema. Thyroid acropachy is a condition characterized by clubbing of the fingers and toes, swelling of the hands and feet, and periosteal new bone formation, typically seen in patients with Graves' disease, which is a form of hyperthyroidism.
Which of the following statements best describes Cushing's syndrome?
- A. Cushing's syndrome refers to a disease process caused by abnormally high levels of cortisol
- B. Cushing's syndrome refers to a disease process caused by abnormally low levels of aldosterone
- C. Cushing's syndrome refers to a disease process caused by abnormally high levels of aldosterone
- D. Cushing's syndrome refers to a disease process caused by abnormally low levels of cortisol
Correct Answer: A
Rationale: Cushing's syndrome is a condition characterized by excessive levels of cortisol in the body. Cortisol is a hormone produced by the adrenal glands that helps regulate various bodily functions, including metabolism, immune response, and stress response. When there is an overproduction of cortisol, either due to excessive production by the adrenal glands or prolonged use of corticosteroid medications, it can result in Cushing's syndrome. Symptoms of Cushing's syndrome include weight gain, particularly in the face and abdomen, high blood pressure, muscle weakness, and irregularities in menstruation. It is important to diagnose and manage Cushing's syndrome to prevent potential complications such as diabetes, osteoporosis, and cardiovascular disease.
All of the following are noted in Cushing's syndrome except:
- A. Psychosis
- B. Systemic hypertension
- C. Sexual precocity
- D. Osteoporosis
Correct Answer: C
Rationale: Cushing's syndrome is a collection of signs and symptoms caused by prolonged exposure to high levels of cortisol. Common features of Cushing's syndrome include weight gain, central obesity, moon face, buffalo hump, easy bruising, muscle weakness, and menstrual irregularities in women.