Endocrine Flashcards
How is the endocrine system arranged
Starts in Hypothalamus (part of the brain), interacts with pituitary gland, which sends a signal to bind to a gland, negative feedback loop
Name the hormones the thyroid prodcues to regulate metabolic activity
T3 and T4
Name the hormones the thyroid produces to regulate metabolic activity
T3 and T4
How does the pituitary act on the thyroid from the hypothalamus
Hypothalamus produces Thyrotropin-releasing hormone (TRH), to act on pituitary
Pituitary produces Thyroid-stimulating hormone (TSH)
what is Thyrotropin-Releasing Hormone
Hormone secreted from the hypothalamus to act on the pituitary to stimulate it to act on the thyroid
How can you identify a Goiter? (swollen thyroid)
The swelling will move when pt swallows
What causes ‘Derbyshire neck’/ Goiter?
Iodine deficiency
Iodine needed for thyroid hormones, thyroid grows in size to try and compensate for lack of
What causes Hypothyroidism
Low T3/T4 hormone levels
Iodine deficiency, drugs, autoimmune thyroid damage, radio-iodine therapy
Signs and symptoms of Hypothyroidism
Gain weight, loss of appetite, loss of energy, low BP/HR, intolerance to cold, depression
Signs and symptoms of Hyperthyroidism
Tachycardia, AF, palpitations, weight loss, tremor, anxiety
What do T3/T4 do?
Increase metabolic rate
Management of Hypothyroidism
thyroxine tablets, thyroid hormone replacement therapy
Management of Hyperthyroidism
Surgical removal of gland, radio-iodone to damage the gland a little bit
Name 4 hormones the adrenal glands produce
- glucocorticoids (cortisol)
- mineralocorticoids (aldosterone)
- adrenaline/noradrenaline
- Androgens (develop sexual characteristics)
What is the function of glucocorticoids?
Glucose metabolism, sugar and energy balance
Describe the pathway from hypothalamus to adrenal gland
Hypothalamus produces Corticotrophin-Releasing hormone (CRH) for pituitary
Pituitary produces Adrenocorticotrophic hormone (ACTH) for adrenal gland
How does the negative feedback loop work for the adrenal gland
Hypothalamus produces CRH for pituitary to stimulate it to produce ACTH to act on adrenal gland, produces cortisol which is detected by hypothalamus to reduce production of CRH
how is the adrenal -ve feedback loop important in prescribing?
Prescribing corticosteroids for inflammation, works as a imitator or cortisol so will be detected and reduce levels of CRH and reduce adrenal gland action
What is the cause of Cushing’s syndrome
Excess cortisol (too much cortisol)
What are the signs and symptoms of Cushing’s Syndrome
(cortisol controls metabolism)
-Diabetes
-Central Obesity
-Acne
-Peripheral wasting
- thin hair, facial hair, thin skin
Causes for Cushing’s Syndrome
[Cushing’s syndrome is just the name for having the characteristics from too much cortisol]
- Cushing’s disease = pituitary adenoma secreting too much ACTH
- too many steroids prescribed
- another tumour producing ACTH
What is another name for Addison’s disease?
Primary Adrenal Insufficiency
What are the symptoms of adrenal insufficiency?
Very non-specific:
malaise
weight loss
nausea, vomiting, abdominal pain
fatigue, depression
muscle and joint pain
Cause of Addison’s Disease
Autoimmune destruction of the adrenal gland
Cause of secondary adrenal insufficiency
Exogenous steroid medication, will act on hypothalamus like cortisol to initiate -ve feedback loop
What is an Addisonian crisis
When the body experiences a stress event, it cannot produce extra cortisol like it would normally because it is being suppressed through secondary adrenal insufficiency
How can you prevent Addisonian Crisis, and how does it present?
Take extra steroids on the day of surgery/extractions
Presents the same as addison’s
What are the post-op instruction after surgery with addisonian cover
need to make sure pt understands that:
- they must keep taking steroids
- if the get dry socket, infection, pain, must keep up and maintain fluids
- have a steroid rescue pack
What controls the body’s calcium levels
Parathyroid gland and the parathyroid hormone
how does parathyroid hormone (PTH) work?
- PTH causes bone resorption, osteoclasts to break down bone to increase calcium levels
- PTH causes kidneys to stimulate Vit D3 conversion to calcitrol (stimulates gut Ca absorption)
What stimulates parathyroid hormone release?
Low blood calcium levels
What does Calcitriol Do?
Converted from Vit D3, stimulates Ca absorption in the gut
What will be the result of hypoparathyroidism?
Hypocalcaemia as PTH isn’t being released to increase serum Ca levels
Causes of hyperparathyroidism
- PTH secreting tumour
- Parathyroid tumour
- Renal failure (/Vit D deficiency)
Signs and symptoms of hyperparathyroidism
- Stones (more calcium to create duct stones)
- Bones (osteoporosis, bone weakening)
- Abdominal groans (constipation)
- Psychic moans (important in CNS functioning)
