Endocrine Disorders Flashcards
Functions of the Endocrine System (2)
- helps maintain physiological homeostasis
- includes tissues that secrete hormones into the blood
How do hormones work?
bind to specific receptors that allow the hormone to exert its effect
secretion of most hormones are regulated by a _____ feedback system
negative
-specific hormones are turned on or off by specific physiological changes
The hypothalamus is a major link between ____ and _____ systems
nervous and endocrine system
the nervous system triggers the release of hormones by the endocrine system
What are the two parts of the pituitary? (both are attached to the hypothalamus)
- posterior pituitary- storage
- anterior pituitary- active part of endocrine
Why is the hypothalamus so important?
- synthesizes and secretes regulatory hormones
-releaseing hormones- simulates release of anterior pituitary hormones
-releases inhibitory hormones- inhibits releases of ant pituitary hormones - synthesizes 2 hormones that are stored in the posterior pituitary
what is the role of the posterior pituitary and what hormones are there?
storage
-oxytocin
-vasopressin
what is the flow of events for anterior pituitary hormones to be released
hypothalamus—releases a hypothalamic releasing or inhibiting hormone into the Hypophyseal portal system—the anterior pituitary recognizes the hormones and releases the proper anterior pituitary hormone
Corticotropin releasing hormone from hypothalamus releases what from anterior pituitary?
adrenocorticotropic hormone
Growth hormone-releasing hormone causes releases of what from anterior pituitary?
growth hormone while somatostatin inhbits it
Thyrotropin releasing hormone releases what from anterior pituitary?
Thyroid stimulating hormone and prolactin
Explain the hormone that causes the following Pituitary disorders:
1. Acromegaly/gigantism-
2. Cushing’s Disease-
3. Diabetes Insipidus-
- acromegaly/gigantism- too much growth hormone
- cushing’s diseases- too much cortisol
- diabetes insipidus- too little vasopressin (ADH)
What are the common symptoms of a pituitary disorder?
Headache
visual changes (double vision, vision loss, drooping eyelid)
whats the difference between Gigantism and Acromegaly?
Gigantism- excessive secretion of GH in children
Acromegaly- excessive secretion of GH in adults
What two hormones are stored by the posterior pituitary?
- ADH vasopressin
- oxytocin
what does ADH vasopressin do?
sensitive to changes in blood tonicity, releases more vasopressin upon water loss
increased water resorption in the kidneys
When is ADH released?
reduced blood volume (baroreceptors sense low BP)
Increased plasma osmotic pressure (osmoreceptors in the hypothalamus sense increased solute in blood)
Does ADH increase or decrease during happy hour
increased because it is sensitive to the decreased blood volume and dehydration
What are common characteristics of Diabetes Insipidus?
peeing alot and having excessive thirst and increased appetite
What are the 2 causes of diabetes insipidus?
- posterior pituitary does secrete ADH
- insensitivity of kidney to ADH
What do you need to do if you are exercising with a patient with DI?
make sure the patient stays hydrated
watch for signs of dizziness, hypotension
muscle weakness
what are the 3 Ps of Diabetes insipidus?
polydipsia- excessive thirst
ployuria- increased urination
polyphagia- increase appetite
Do patients with DI have an problem with glucose metabolism
no
what are some adrenal gland disorders?
Hyper-functioning
1. cushing’s disease/syndrome
2. hyperaldosteronism (conn’s syndrom)
3. pheochromocytoma
Hypofunctioning
1. hypoaldosteronism/addison’s disease
explain the release of cortisol
hypotalamus releases corticotropin—-corticotropin hormone goes to anterior pituitary—-ant pituitary releases adrenocorticotropic hormone into vascular system
ACTH is carried in the blood to the adrenal cortex stimulating the adrenal cortex and sythesis of cortisol–stress hormone
normally as cortisol synthesis increases what happens to the CRH production
as cortisol increases then CRH from the hypothalamus should decreases and ACTH should decrease as well
What are the functions of cortisol?
Stress hormone- think fight or flight
1. counter-regulatory to insulin- promotes hyperglycemia
2. decreases bone formation (decrease osteoblast formation) and decreases CA++ absorption
3. acts as a diuretic
4. inhibits production/release of inflammatory mediators
Does cortisol production have a role in osteoporosis?
yes
Hyper-secretion of cortisol causes what disease
cushing’s disease and syndrome
what are some hallmarks of patients with cushing’s disease?
- rapid weight gain in central area
-moon face
-buffalo hump - skin- thinning of skin and capilllary–bruising easily
-poor wound healing - muscle wasting and weakness
- tachycardia; hypertension
- osteoporosis
- hyperglycemia/DM
-stres response - immunosuppression/increased infection risk
What is the treatment of cushing’s diseases/syndrome
depends on the reason for excess cortisol
- pituitary tumor removal-disease
-syndrome- adrenal tumor removal
What is the primary functions of the Thyroid Gland (4)
- increased basal metabolic rate
- important for brain and muscular development
- increases HR/contractility and cardiac output
- CNS arousal state
what are common signs/sx of hyperthyroidism
-unintended weight loss
-anxiety
-heat intolerance
-fatigue
-tachycardia/hypertension/afib
-tremors
-hyperglycemia
-osteopenia (longterm)
what is graves disease?
autoimmune disease- hyperthyroidism
-causes bulging of eye anteriorly
-thyroid eye disease
Typical treatment for hyperthyroidism
medication that inhibits the conversion of T4 to T2
betablockers for the CV
What are sx/symptoms of hypothyroidism
-lethargy and fatigue
-bradycardia
-edema
-weight gain
-cold intolerance
-dry skin/brittle hair and fingernails
-goiter
What is the function of the parathyroid gland and how many are there?
- secretes parathyroid hormone
- regulates plasma calcium (osteoclast activity)
- regulates phosphate level
there are 4
Too much Parathyroid hormone increase risk of _____-
osteoporosis
Function of parathyroid hormone?
increases blood calcium concentrations when serum CA++ is too low (hypocalcemia)
-stimulates osteoclasts to relasese more CA++ from bone
-deceases CA++ by kidney
-activates vitamin D which stimulates the uptake of Ca++ from diet
What are some modifiable risk factors for osteoporosis?
vitamin D deficiency
lack of physical activity
weight loss
cigarette smoking
alcohol consumption
stress
what are non-modifiable risk factors for osteoporosis
-history of falls
-older age
-gender
-white and asian
-prior fracture
-family history of osteoporosis
What are medical conditions that are associated with increased risk of osteoporosis?
-prolonged corticosteroid use
-hypogonadism
-hyperparathyroidism
-chronic liver and renal
-inflammatory diseases
-DM
-dementia
Increased/decreased survival age after hip fracture
decreased
___ fractures are associated with morbidity and decreased ability to cary out independent activities of daily living
ALL fractures
DXA scans help diagnose osteoporosis how?
T score compare bone mineral density to a healthy 30 year old femal
z scores compare bone density to average people of own age and gender
Bisphosphonates are used for what?
FDA approved drug for osteoporosis
How do bisphosphonates work
inhibit bone resorption by attaching to bony surfaces and inhibiting the action of osteoclast
What are Interventions used to prevent osteoporosis?
stop smoking
medication
check risk factors
reduce alcohol
weight bearing exercise
vitamin D and Calcium increase
What are some key items to remember when working with a patient with osteoporosis?
typically same FITT principles but emphasis on extension while avoiding loaded trunk flexion/rotation activities
