Endocrine Flashcards
Where is aldosterone synthesised
zona glomuerulosa
Where is cortisol synthesised
zone fasciculata
What is the pitutary gonadal axis controlled by
hypothalamus
Where are gonadotrophic hormones secreted
Pituatary
What does follicle stimulating hormone cause in males
to produce sperm
What does follicle stimulating hormone cause in females
to grow ovarian follicle hormones and therefore secrete oestrogen
What does leutinizing hormone cause in males
testosterone production
What does leutinizing hormone cause in females
ovulation and progesterone production by the corpus luteum
Pathway of estrogen and progesterone being released
Hypothalamus -> GnRH -> anterior pituitary-> LH + FSH-> Ovaries -> estrogen and progesterone
Pathway of testosterone being released
Hypothalamus -> GnRH -> anterior pituitary -> LH + FSH -> Testes -> testosterone
What happens to potassium when insulin is used>
Na/K ATPase pump is stimulated to translocate potassium and decrease it’s levels
What is required for PTH secretion
magnesium
Where does parathyroid hormone act in the kidney to increase parathyroid hormone
Distal convoluted tubule
What can cause an ADH deficiency
Damage to the posterior pituitary
What does antidiuretic hormone cause
Water reabsorption by insertion of aquaporin-2-channels in the collecting duct
Where does the antidiuretic hormone act
the collecting ducts
What is prolactin release inhibited by
Dopamine
What does somatostatin do
inhibits secretion of glucagon
What does the adrenal cortex synthesise
aldosterone and cortisol
What does the adrenal synthesise
adrenaline and noradrenaline
What do sertoli cells produce
androgen binding protein
In acromegaly, what does increased levels of growth hormone cause?
increased IGF-1 from liver which stimulates overgrowth of tissues and alters blood/glucose lipid metabolism
What does aldosterone cause?
Reabsorption of sodium and water and excretion of potassium -> increased blood volume
How is cranial diabetes insipidus diagnosed?
Diagnosed by low urine osmolality after fluid deprivation but then normalised osmolality after desmopressin is given since the underlying pathology is deficiency is hormone quantity
What is the investigation for Cushing’s syndrome?
low dose dexamethosome depression test
Describe MEN type 1
3Ps: parathyroid, pituitary and pancreas (recurrent peptic ulceration)
MEN 1 gene
Presentation of hypercalcemia
Describe MEN type 2
2Ps: phaecromocytoma, parathyroid
Medullary thyroid cancer in 70%
RET oncogene
Describe MEN type 3
1P: phaecromocytoma
Medullary thyroid cancer
Marfanoid symptoms, neuromas
RET oncogene
What is Chovesteks sign
Increased irritability to peripheral nerves due to hypocalcemia
SE of carbimozole
Agranulocytosis - sore throat
What are psammoma bodies seen in
papillary carcinomas- clusters of microcalcifications
What electrolye abnormality is seen in addisons
Hyperkalemia and hyponatremia
What two hypothalmic hormones can increase secretion of prolactin
Prolactin realising hormone and thyrotropin releasing hormone
What is DKA
Uncontrolled lipolysis
What happens to hormones in kallmans syndrome
Low FSH, LH and testosterone
What is subacute thyroiditis or de quervains
Hyperthyroidism secondary to viral infection can present with painful goitre. MM- self limiting and manage with NSAIDs
How does lithium cause DI
Nephrogenic DI by blocking ADH receptors in collecting duct
What is Waterhouse-Friderichsen syndrome caused by
Neisseria meningitidis
Describe hyperglycaemic hyperosmolar syndrome
Severe hyperglycaemia without significant ketosis. Similiar pathophysiology to DKA but there is still small amounts of HHS being secreted this can prevent a DKA by suppressing lipolysis and ketogenesis.
Symptoms- Marked dehydration due to hyperglycaemia and osmotic diuresis (hyperosmolar urine)
Characterised by profound hyperglycaemia >33.3 mmol, serum osmolarity >320mmol
MM- 0.9% saline without insulin
What are common investigations for infertility
Rubella immunity/Chlamydia screen, Ovulation test/Semen analysis and Tubal patency test
What is a group 1 ovulatory disorder
Hypothalamus dysfunction characterised by low levels of gonadal hormones
What is a group 2 ovulatory disorder
Hypothalmic pitatary dysfunction with normal levels of gonadal hormones
What is a group 3 ovulatory disorder
Ovarian failure
When should the DVLA be contacted
If a patient has one or more severe episode of hypoglycemia whilst driving
If they use insulin
Range for impaired glucose tolerance
7.8-11mmol/l
Secondary Hyperparathyroidism?
Due to low vit d or CKD
High PTH + low/normal calcium with raised phosphate
Blood results in tertiary hyperparathyroidism
High PTH and hypercalcaemia
What diabetes medication cause weight loss
SLGT2i and GLP-1 receptor antagonists
What diabetes medications cause weight gain
Sulfonylureas (gliclazide) and thiazolidines
What diabetes medications are weight neutral
DPP4i- gliptin
Examples of SGLT2i
Empagloflozin, dapagloflozin
Examples of DPP4i
Gliptins
Examples of thiazolidines
Piaglitozone
Where is GLP-1 produced
Ileum
Example of GLP-1 receptor agonist
Exenatide
What is dexamethasone an example of
A steroid with high glucocorticoid activity, minimal mineralocorticoid activity
GLP-1 and GIP are what
Incretins
