Encodrine Flashcards
two types of hormones?
difference in cell interactions?
examples?
water soluble and fat soluble
water - bind to surface - peptides
fat - diffuse into cell - thyroid hormone
hormones classes?
peptides
amines
iodothyronine
cholesterol deriavtives and steroids
where do fat soluble binds to?
cytoplasm or nucleus
method of travel for adrenocortical and gonadal steroids?
95% protein bound
fate of progesterone in testes or adrenals?
adrenals - cortisol
testes - androstenedione - testosterone
ovaries - estrodione
control of hormone action?
hormone metabolism - increased metabolism to reduce fundtion
hormone receptor induction
hormone receptor down regulation
synergism - combined effects of two hormones amplified - glucagon with spinepherine
antagosim
pititary growth problems signs
tumour mass effects - blindness
hormone excess - tumour producing excess prolactin, GH, TSH
Hormone deficiency - tumour destroys pituiatry tissues
request MRI
half life of T4 ?
5 TO 7 DAYS
half life of T3?
2 days
function of thryoid hormone?
growth rate accelerated
enhances fat metabolism
accelerates food metabolism
increases protien synthesis
increase ventilation rate
stimulation of renin
low sodium
drop of blood volume
drop in blood pressure
weight regulation dependant on?
envrioment and genes - homeostatic system
adipose tissue sends feedback
leptin?
satiety hormone
leptin receptor found in hypothalamus
MAIN ORGAN WHich regulates appetite in brain?
hypothalamus
hormones which increase/ decrease appetite in hypothalamus?
NPY/ AGRP - INCREASE appetite
POMC - decrease appetite
percentage of ingested glucose goes where?
40% to liver
60% to muscle
role of glucagon?
increase hepatic glucose output via
- gluconeogenesis
- glycogenolysis
reduced peripheral glucose uptake
stimulate peripheral release of gluconeogenic precursors (amino acids)
- lipolysis
how does diabetes cause morbidity and mortality?
causes
diabetic ketoacidosis
hyperosmolar hyperglycaemic state
macrovascualr and microvascular tissue complications
- retinppathy (loss of sight)
- diabetic neuropathy
- stroke
- CV
what other hormones are realeased when blood sugar is low?
- GH
- cortisol
- adrenaline
types of diabetes
type 1
type 2
MODY - monogenic diabetes
pancreatic diabetes - pancreas stops working (damage from surgery)
endocrine diabetes - cushings syndrome
malnutrition diabetes
hyperosmolar hyperglycaemic state?
hyperglycemia but no acidosis
- still enough insulin to prevent lipolysis - excessive production of ketones - no acidosis
why is HBA1C levels used?
long term trend of blood sugar
glucose attaches to RBC which have lifespan of 3 months
describe the ideal drug to treat T2 diabetes
-reduce appetite and induce weight loss
- preserve beta cells and insulin secretion
- increase insulin secretion at meal times
- inhibit counterregulatory hormones
- not increase rick of hypoglycemia
role of GLP - 1
stimulates insulin secretion
reduces appeptite
slows gastric emptying
what counteracts glp -1
DPP 4
role of SGLT 2 inhibitors
lock reabsorption of glucose in kidnets increasing glucose excretion in urine
lowering blood glucose levels
why does obesity cause T2D?
obesity impairs insulin action
excessive adipose issue causes insulin resistance
benefits and risk of tight glucose control?
reduces risk of retinopathy but increase risk of hypoglycaemia
basal vs bolus insulin?
bolus - quick acting taken before meals
basal - long acting
insulin treatment of T1DM ?
pre meal - bolus
adjusted to what is in the meal
between meals and at night - basal
aim to maintain blood sugar between 4-7 mmol/l
levels of hypoglycaemia?
level 1 - <3.9 mmol/l - no symptoms
level 2 - <3mmol/l
level 3 - require third party help
what other factors can cause hypoglycaemia?
sleep and exercise
impaired awareness of hypoglycaemia?
excessive drops in blood glucose - brain stops responding
no symptoms but dangerously low blood sugar
third line of defense for diabetics when blood sugar low?
adrenaline
because no insulin and no glucagon storage left
Acromegaly vs gigantism ?
Gigantism - excessive GH during childhood and dont go through puberty
Acromegaly - excessive GH from tumour during adulthood
why is a pelvic ultrasound done on pubertal patients?
- mullerian structures present?
- morphology of uterus
- morphology of ovaries
maturation of external geniltalia under oestrogens?
- labia majora and minora increase in size
- rugation and change in color of labia majora
- Hymen thickens
- clitoris enlarges
what causes oubic hair in girls?
adrenal and ovarian androgens
precocious psuedopuberty?
signs of puberty - release of adrenal sex hormones
so low LH and FSH
how many effected with turner syndrome?
1 in 2000 girls
otitis media
inflammatory infection of middle ear
results FROM primary and secondary hyperthyroidism investogations
TFTs:
Primary (negative feedback) – low TSH, high T3/T4
Secondary – high TSH, high T3/T4
antibodies only present in graves disease?
TSH receptor antibody (TRAb) – Graves only
signs of drug induced hyperthyroidism?
only thyroid hormones is raised
treatment of hyperthyroidism?
beta blocker - decreases SNS activation
1st line: Carbimazole – anti-thyroid drug
- Blocks thyroid hormone synthesis
radioiodine - damages hyperplasia thyroid cells
thyroidectomy
complication of hyperthyroidism?
thyroid storm - thyroidtoxicty - too much t4
coma, AF, delirium and death
osteoporosis
elphantisis
describe autoimmune thyroiditis causing hypothyroidism?
hashimoto thyroiditis
antithyroid autoantibodies (anti tpo antibodies and anti thyroglobulin) cause atrophy of thyroid follicles
CD8 mediated - induce apoptosis
how does amiodarone cause hyper or hypo thyroidism ?
Amiodarone
Can cause hyperthyroidism due to high iodine
Can cause hypothyroidism as it inhibits the conversion of T4 to T3
acromegaly def?
gigantism def?
- excessive production of growth hormone occurring in adults after fusion of the epiphyseal plates
- excessive production of growth hormone occurring in children before fusion of the epiphyses of long bones
what can increase GH secretion?
low blood glucose
increased sleep
increased excercise
lack of food
increased stress like trauma
methods limiting gh release?
- increase in GHRH signals hypothalamus to stop producing GH
- GH causes somatomedins released - ant pit stop producing GH
- GH signal hypothalamus to produce somatostatin to ant pit to stop GH release
direct effect of GH ?
indirect effect?
organ growth
increase in insulin resistance - high blood insulin
IGF-1 IS PRODUCED
increased cellular metaboism
role of dopa mine in prolactin release?
overrides thyrotropin releasing hormone which stimulates releases of prolactin
inhibits prolactin release
effect of high levels of prolactin?
increase dopamin - inhibits further prolactin release
inhibits release of gonadotropin (grh)
aetiology of prolactinoma?
benign adenoma of the pituitary gland producing prolactin
functioning tumour
which part of the kidneys is not under control by pituitary gland?
adrenal medulla
where is testosterone mainly produced?
In the testicles
WHATS another name for ADH?
AVP - arigine vasopressin
main regulation of calcium metabolism
parathyroid gand
where is avp produced?
hypothalamus because release from post pituitary - post pituitary doesnt synthesize anything
ROLE OF GROWth hormone on which cells and organs and what effect do they have
- liver - gluconeogenesis
IGF1 synthesised in liver from gh - fat cell - lipolysis
- skeletal muscle - increased amino acid uptake / protein synthesis
receptor for GH
growth hormone receptor - enzyme linked receptor
symptoms of excess GH secretion
polyuria
sweating
joint pain
headaches
swollen hands n feet