Disorders of Endocrine Function Flashcards
(26 cards)
What is a primary endocrine disorder?
Originate in target organ releasing the hormone
What are secondary and tertiary disorders?
Defect in hypothalamus-pituitary system
Causes od endocrine dystfunction can be grouped into____ which are?
- Hypofunction
- Hyperfunction
- Hormone resistance of target cells
Hypofunction is due to?
- Congenital defects resulting in absence or impaired development of the gland
- Absence of an enzyme needed for hormone production
- Destruction of a gland due to decreased blood flow, infection, neoplastic growth, autoimmune responses
- Decline of function due to aging or atrophy of the gland due to medication
Hyperfunction(excessive activity or function) is due to?
- Excessive hormone production due to over stimulation of the gland
- Hormone producing tumor
Hormone resistance of target cells such as?
Reduced intracellular responsiveness (e.g. type 2 diabetes)
Blood tests are an important test for info on levels of____ analyzed by?
Hormones and Analysed using radioimmunoassay (RIA); ELISA; autoantibodies; biochemical, etc
Stimulation Test?
For Testing hypofunction of an endocrine gland
1. A tropic or stimulating hormone is administered to test the ability of an endocrine organ to increase hormone production
2. If you get an increase in hormone production, then the gland is working well
What is Suppression Test?
Used for testing hyperfunction of an endocrine gland
1. Normal negative feedback mechanism of an endocrine organ is not working:
→excessive amount of hormone is being produced
2. If stimulus does not result in reduction then hyperfunction
Body’s major metabolic hormone - Thyroid hormone affects virtually every?
Cell
Thyroid H are found in 2 forms?
- T4(thyroxine): major form secreted by thyroid follicles (90%)
- T3(triiodothyronine): thought to be active form;
Most T3 converted from T4 at tissue level
TSH – gives an initial indication of?
Thyroid function
Following an abnormal TSH result, what tests are required?
- Serum FT4 (and FT3)
- Thyroid antibody test
The most common cause of hyperthyroidism?
Graves’ disease
1. Autoimmune disease: The body makes abnormal antibodies directed against thyroid follicular cells
What happens in Grave’s disease?
Antibodies mimic TSH, stimulating TH release
Hyperthryoidism can cause Exophthalmos which is?
Eyes protrude as tissue behind eyes becomes edematous and fibrous
Most symptoms of hyper can be attributed to 2 main causes?
- Hypermetabolic state
- An increase in SNS activity
Treatments for hyper?
Carbimazole tablets (a thionamide), surgical removal of thyroid or radioactive iodine to destroy active thyroid cell
Congenital hypothyroidism (CH) causes?
- Defect in gland development (e.g. may be absent, underdeveloped)
- Problem with thyroid hormone biosynthesis (e.g. as a result of a gene defect
Causes of aquired hypothyroidism?
- Autoimmune disease e.g. Hashimoto’s thyroiditis, thyroidectomy, ablation, iodine deficiency
- Symptoms include decreased metabolic rate, lethargy slow pulse, weight gain, cold intolerance, constipation, puffy face, etc
- Treatment is replacement therapy with synthetic preparations e.g. levothyroxine
During high BGLs?
beta cells release insulin to put glucose into cells
During low BGLs
Alpha cells release glycagon which release glucose into cells
GLUT 1 transporters?
Are present in nearly all tissues but are important transporters for RBCs & brain
GLUT 2?
Main transporter of the beta cells (of the pancreas), liver & kidney
