Week 11- Endocrine System Flashcards
What is hashimoto thyroiditis
Autoimmune
Goitre and lymphocytic infiltration of the thyroid
Mc areas where idione levels are sufficient
45-60
F>M 10:1
Feeling of pressure in throat
What is global hystericus
Feel like there’s a lump in your throat
Anxiety caused
Hypoparathyroidism
• Less common
• Usually surgically induced
S&S
• Tetany (neuromuscular irritability)
• Paraesthesia’s of distal extremities
• Laryngospasm
• Generalised seizures
• Anxiety/depression
• Ocular disease (cataracts ad calcification of lens)
• Dental abnormaliti
What is the pancreas
A soft, lobulated and elongated organ
• A gland that is partly exocrine and partly endocrine.
• The exocrine secretes the digestive pancreatic juice.
• The endocrine part secretes hormones e.g. insulin
• Lies posterior to stomach, at the level of L1 and L2
• Consists of Islet of Langerhans cells made up mainly
from:
- β cells: produce insulin which regulates
blood glucose levels
- α cells: secretes glucagon which stimulates
glycogenolysis in the liver and thus increases blood
sugar
What is the affect of insulin on blood sugar
It decreases blood sugar levels
What is diabetes Mellitus type 1
Autoimmune disease destruction of islet of langerhan cells in genetically predisposed individual
Less common
Insulin deficiency
Childhood or Y/A
MC no family history
Risk Factors
Maternal age/gestational infection
Viral infections
Diet (early introduction to cows milk, Vit D deficiency)
Environmental toxins
Childhood obesity
Psychological stress
What is diabetes Mellitus type 2
• MC form of DM
• Accounting for around 90% of cases
• One of the mc non-communicable diseases
• Aetiologies; genetic susceptibility, ageing, low birth weight, obesity, diet,
physical inactivity, urbanisation.
Pathogenesis
Insulin resistance: Decreased response of peripheral tissues (esp. liver,
skeletal mm) to insulin
β -cell dysfunction: Inadequate insulin secretion in the face of insulin
resistance and hyperglycaemia
Why are the symptoms of diabetes widespread
Because it involves the circulatory system
what is a pancreatic neuroendocrine tumours
• Tumours of the pancreatic islet cells
• Rare
Hyperinsulinism (Insulinoma)
• Β –cell tumours
• MC pancreatic endocrine tumour
• Produce sufficient insulin to induce clinically significant hypoglycaemia
Gastrinoma (Zollinger-Ellison Syndrome)
• Hypersecretion of gastric acid
• Associated with pancreatic islet cell lesions
• Invasive
• Lead to duodenal and gastric ul
What is hypoadrenalaism
Adrenal cortex , adrenal glands on top of both kidneys
Caused by overproduction of 3 major hormones of the adrenal cortex
1. Cushing Syndrome: an excess of cortisol (HYPER)
2. Hyperaldosteronism: a result of excessive aldosterone
3. Adrenogenital or virilizing syndromes: excess of androgen
What is Cushing syndrome
• Hypercortisolism
• Mc cause exogenous glucocorticoids (iatrogenic Cushing syndrome)
• ACTH-secreting pituitary tumours account for 60-70% of cases
• F>M, 4:1
• 30-60 years
• Insidious onset
S&S
• Early stages may present with HT and weight gain
• With time, truncal obesity moon face, buffalo hump
• Hyperglycaemia, glucosuria and polydipsia
• Skin – fragile, thin, bruises easily, cutaneous striae on abdomen
• Mood swings, depression, psychosis
• Hirsutism (facial hair)
what is adrenal hyperplasia
Excessive production of sex hormones (maily sex hormones)
What does addisons disease affect
Adrenal insufficiency as they don’t make enough of certain hormones like cortisol ‘stres hormone’
MC Symptoms
Fatigue
Muscle weakness
Loss of appetite
Weight loss
Abdominal pai
Can be autoimmune disease or suddenly stopping steroid medicines
What is Pheochromocytoma
Adrenal Medulla
• Major source of epinephrine and
norepinephrine in the body
• Closely associated with the ANS
Pheochromocytoma
• Neoplasms in adrenal medulla
• A rare cause of surgically correctable HT
• MC sign is HT (90% of patients)
• Paroxysmal episodes – abrupt elevations in
BP associated with tachycardia, H/A,
sweating, tremo
What is the pineal gland
Regulates sleep circadian rhythms,
Can affect sexual development and mestural cycle
Releases melatonin
What is melatonin deficiency
Insomnia or seasonal effectiveness disorder (SAD)
Anxiety
Elevated oestrogen and progesterone levels
Immune suppressions
What is Melatonin excess
Associated with SAD
Lower oestrogen and progesterone levels
Low thyroid and adrenal function
Hypotension- low BP
What is the pituitary
Pea shaped gland located at the base of the brain, inferior to hypothalamus.
Regulates crucial bodily functions by secreting hormones that influence other glands in the endocrine system.
2 main lobes:
Anterior lobe (release its own hormones)
Posterior lobe (stores and releases hormones from hypothalamus )
Hormones of anterior pituitary are:
GH: stimulates growth, cell regeneration and reproduction
ACTH: stimulates adrenal glands to release cortisol
TSH: regulates thyroid gland activity
LH: control reproductive process including ovulation and sperm repoducrion
FSH: control reproductive process including ovulation and sperm repoducrion
Prolactin: promotes milk production
hormones of posterior pituitary are:
Oxytocin: childbirth, social bonding
Antiduiretic hormone: regulates water balance by affecting kidneys
what does the endocrine system regulate
Metabolism
Secretion of hormones
chemical composition and volume of internal environment
contraction of smooth and cardiac muscle fibres
Certain activities of the immune system
Reproduction and growth
list 3 classifications of hormones
Autocrine: acts on the signalling cell
- Paracrine: acts on nearby cells
- Endocrine: Uses the circulatory system to
transport hormones
list classifications of glands
Endocrine Glands: Secrete hormones directly
into the blood stream (pituitary, pancreas,
thyroid, adrenal)
- Exocrine Glands: Secrete hormones into ducts
(sweat, salivary, mammary, stomach, liver) - Heterocrine Glands: Glands that perform both
endo and exocrine functions (pancreas)
what is the pituitary gland
base of the brain within the sella turcica
* The size of a pea
‘master gland’
controls release of hormones that influence other glands and organs such as the thyroid, adrenal gland, ovaries and testes
anterior and posterior
regulated by signals from the hypothalamus
what is the anterior pituitary known as
adenohypophysis
what is the posterior pituitary known as
neurohypophysis
neurosecretory cell
list some pituitary diseases
hperpituitarism
hypopituitarism
what is acromegaly
20-40 years
* Thick lips
* Tongue changes size and
shape
* Protruding jaw
* Heigh, puberty and gonad
development unaffected
* Associated with
cardiovascular effects
including cardiomyopathy,
HT, valve dysfunction,
arrythmias, DM and various
malignancies
what is cushings disease
overproduction of cortisol
adrenal tumour or pituitary tumour formed by overproduction of ACTH stimulates this overproduction
thin skin
purple/red stretch narks
muscle wekness
high bp
mood change
irregular period
fatigue
facial hair growth
thyroid function
regulates metabolism, growth and development
formation and secretion of thyroid hormones and iodine homeostasis
T4 (Thyroxine) inactive
T3 triiodothyronine (active thryroid hormone)
they regulate
metabolic rate
heart muscke
digestive function
brain development
bone maintenance e
signs and symptoms of hyperthyroidism
symptoms:
Increased hunger
Weight loss
Heat intolerance
Palpitations
Excessive sweating
Nervousness
Muscle weakness
Asthenia
hyper defectaion
insomnia
hyperactivity
signs:
goitre
tremor
tachacrdyia
warm moist palms
eye wide stare
brisk tension refexes
cardiomegaly
osteoperosis
proximal muscle weakness
hypothyroidism
functional derangement that interferes with
the production of thyroid hormone
- Prevalence increases with age
- F>M, 10:1
- Can result from a defect anywhere in the hypothalamic-pituitary-thyroid axis
- Can be: Primary (intrinsic thyroid abnormality)
Congenital (iodine deficiency), autoimmune (mc. Hashimoto’s thyroiditis),
iatrogenic
Secondary (pituitary or hypothalamic disease) - Vast majority of case accompanied by goitre enlargement
graves disease
hyperthyroidism a form of
goitre
bulging eyes
mc 20-40
f>M
the production of autoantibodies against the TSH receptor
what controls calcium
parathyroid glands
what cells does the pancreas consist of
level L1, L2
islet of langerhan cells made from
b cells- inulin which regulates blood glucose levels
a cells- secretes glucagon which stimulates gyleogenolysis in liver and increases blood sugar
which hormone stimulates sleep
melatonin
