Thyroid And Adrenal Glands Flashcards
Where is calcitonin produced and what does it do?
Paragollicular cells
Reduce calcium levels
What makes T3, rT3 and T4 in respect to DIT AND MIT?
T3- MIT+DIT
T4- DIT+DIT
rT3- DIT+MIT
Are thyroid hormones highly bound to plasma proteins and what concerts T4 into rT3 and T3 and which is more potent?
Yes
Deidoinase enzymes
T3 more potent
What are the main actions of the thyroid hormone?
Increase metabolism in the body
Stimulate growth and development
Synergistic with actions of SNS/ catecholamines
What is the most common cause of hypothyroidism, what is cretinism, how to diagnose and the management of it?
Hashimoto’s thyroiditis
Cretinism- dwarfism & mental retardation
Diagnosis- thyroid function tests of suspected Hashimoto’s then test thyroid antibodies, anti-microsomal, anti-thyroglobulin antibodies
Management: synthetic thyroid hormones, levithyroxine
What is the most common cause of hyperthyroidism, the symptoms, the diagnosis and management?
Graves’ disease
Symptoms: nervousness, palpitations, weight loss, tremor, sweating, heat intolerance and goitre and exophthalmos
Diagnosis: radio-isotope uptake scan, presence of thyroid autoantibodies
Management: anti thyroid drugs
Radio-iodine
Surgery
How do anti-thyroid drugs work and give examples?
Decrease the production of thyroid hormones by inhibiting iodination and coupled processes
Carbimazole, propylthiouracil
How do non selective beta blockers work?
Reduce actions of catecholamines, rapid symptomatic relief if tremor, palpitations and anxiety
When is radioactive iodine used?
When thyrotoxicisis recurs after anti thyroid drug therapy
When is thyroidectomy used?
Severe thyrotoxicisis associated with large goitre or concerns about tumour and when there are obstructive symptoms
What hormones are produced in the adrenal cortex and adrenal medulla?
Cortex- glucocorticoids, mineralocorticoids, weak androgens
Medulla- catecholamines
What regulates androgens?
ACTH
What stimulates the secretion of aldosterone, where does it work?
Increased potassium and angiotensin 2
Act on DCT and CD of kidney to promote sodium retention and k+ elimination during urine formation
How would you treat Conn’s syndrome?
Surgery, aldosterone receptor antagonist
What are the actions of cortisol?
Metabolic effects
Anti inflammatory/ immunosuppressive effects
Role in adaptation to stress
Permissive role in action of other endocrine hormones
Actions on other tissues
