Adrenal Gland Flashcards
5 layers of the adrenal glands
Capsule
Zona glomerulosa
Zona fasciculata
Zona reticularis
Medulla
Which arterial plexus is in the zona glomerulosa
Sub capsular plexus
Which arterial plexus is in the zona reticularis and medulla
Medullary plexus
Which hormones activate the mineralocorticoid receptor
Cortisol
Aldosterone
What conditions cause primary hyperaldosternism
Conn’s syndrome
Aldosterone producing adenoma
Bilateral adrenal hyperplasia
What is the effect of aldosterone binding to mineralocorticoid receptors in the distal convoluted tubule
Incr sodium reabsorption
Incr potassium extretion
What does 11betaHSD-2 do
Converts cortisol to cortisone
Characteristics of Liddle syndrome
Hypertension
Hypokalemia
Metabolic alkalosis
What does ACTH binding to melanocortin-2 receptors cause
Up regulation of steroidogenesis
Glucocorticoid remediable aldosteronism
rare form of hyperaldosteronism‐induced arterial hypertension. autosomal dominant trait in which ACTH increases the activity of existing aldosterone synthase, resulting in an abnormally high rate of aldosterone synthesis and hyperaldosteronism
When are ACTH and cortisol levels highest
Just before waking
When are ACTH and cortisol levels lowest
Night
How do glucocorticoids effect starvation, infection, and hypotension
Cause tissue breakdown for fuel
Cause immunosuppressive
Increase BP
Why does Cushing syndrome cause thin skin and osteoporosis
Muscles, bones, and skin broken down to get subtpstrates for Gluconeogenesis
What condition is caused by too much cortisol
Cushings syndrome
What condition is caused by too little cortisol
Addisons disease
What causes Addison’s disease
Primary renal failure
What are the 4 characteristics of an addisonian crisis
Low BP
Low glucose
Low Na
High K
Cushing’s syndrome treatment
Surgery on pituitary
Radiotherapy on pituitary
Adrenalectomy
Metyrapone/ketoconazole/etomidate
Cushing’s syndrome symptoms
Dorsal fat pad
Thin skin
Easy bruising
Muscle weakness
Osteoporosis
Obesity
Stretch marks
Enlarged heart
High BP
Round face
Ulcers
Addison’s disease symptoms
Fatigue
Weakness
Myalgia
Anorexia
Weight loss
Hyperpigmentation
Addison disease management
Replacement steroid -
Hydrocortisone for glucocorticoid
Fludrocortisone for mineralocorticoid
Addisonian crisis management
IV fluid resuscitation
IM hydrocortisone
What is the most abundant steroid in circulation
DHEA Dehydroepiandrosterone
Adrenarche
Maturation of the zona reticularis at age 8-10
How does adrenarche trigger puberty
Triggers GnRH pulse generator
Adrenal androgens
DHEA
androstenedione
What does congenital adrenal hyperplasia cause
Salt loss
Adrenal insufficiency
Virilisation
Adrenal hyperplasia
What amino acid are catehpcholamines synthesised from
L-tyrosine
Where are chromaffin cells found
Adrenal medulla
Para aortic sympathetic chain
Organ of zuckerkandl
Wall of urinary bladder
Neck and mediastinal sympathetic chain
Types of adrenoreceptor
Alpha 1 and 2
Beta 1 2 and 3
D 1 and 2
Symptoms of catecholamine excess
Impending doom
Diaohoresis
Dyspnea
Headache
Hypertension
Palpitation
Tremor
Nausea
Vomiting
Fatigue
Orthostatic HT
Hyperglycaemia
Weight loss
Epigastric and chest pain
Congestive heart failure
What cells does phaeochromocytoma arise in
Adrenal medulla chromaffin cells
What cells does paraganglioma arise in
Extra adrenal chromaffin cells
What is PPGL
Phaeochromocytoma and paraganglioma
Both chromaffin cell tumours
PPGL signs and symptoms
Hyperadrenergic spells
Resistant HT
Familial yndrome
Adrenal mass
Press or response during general anaesthesia
Early onset HT
Dilated cardiomyopathy
PPGL diagnosis
24 hr urine metanephrines
Plasma metanephrines
CT/MRI adrenals and abdomen
1-MIBG scintigraphy
PPGL treatment
Surgical resection
Pre operative alpha and beta blockade - phenoxybenzamine + propranolol
I-MIBG therapy
Acute crisis - phentolamine or nicardipine
PPGL acute crisis treatment
IV phentolamine or nicardipine
