SUGER: Endocrine Flashcards
What do progesterone, aldosterone, cortisol, testosterone, and estriol have in common?
They are all steroid hormones, made from cholesterol.
What are catecholamines (dopamine, adrenaline, noradrenaline) synthesised from?
Tyrosine.
What are thyroid hormones synthesised from?
Tyrosine and iodine.
The pituitary gland receives blood via the hypothalamic-hypophyseal portal system. What does this mean?
Arterial blood enters the hypothalamus, then travels through the infundibulum to the pituitary gland.
Which part of the pituitary gland releases more hormones, the anterior or posterior?
Anterior.
Posterior only releases oxytocin and antidiuretic hormone (ADH).
Which part of the structure of TSH, LH, and FSH (and hCG) is the same?
The alpha chain (they have different beta chains).
What hormone released by the hypothalamus stimulates the anterior pituitary gland to release TSH (thyroid stimulating hormone)?
TRH (thyrotropin releasing hormone).
What hormone released by the hypothalamus stimulates the anterior pituitary gland to release ACTH (adrenocorticotrophic hormone)?
Corticotropin releasing hormone (CRH).
What hormone released by the hypothalamus stimulates the anterior pituitary gland to release FSH (follicle stimulating hormone) and LH (luteinising hormone)?
GnRH (gonadotropin releasing hormone).
What hormone released by the hypothalamus inhibits the anterior pituitary gland from releasing prolactin?
Dopamine.
The anterior pituitary gland releases ACTH (adrenocorticotropic hormone).
What are the two key functions of ACTH?
Acutely stimulates cortisol release.
Stimulates corticosteroid synthesis.
The anterior pituitary gland releases ACTH (adrenocorticotropic hormone). ACTH acutely stimulates cortisol release. What effect does cortisol have on ACTH release?
Cortisol has a negative feedback effect on the release of ACTH.
Why should cortisol blood test levels for adrenal insufficiency be taken in the morning?
Cortisol has a circadian rhythm, and usually peaks in the morning.
What three bodily states stimulate growth hormone release?
Hypoglycaemia, exercise, and sleep.
Growth hormone is important in linear growth in children and acquisition of bone mass. What other five actions does growth hormone have?
Stimulates protein synthesis, lipolysis, and glucose metabolism.
Regulates body composition.
Psychological well-being.
