LM3 - ppt. 3 endocrine drugs -> pituitary/adrenal/thyroid Flashcards
what is the endocrine system made up of?
- glands located throughout the body
what are these glands called and why?
- they are called ductless
- bc they secrete chemical substances right into the bloodstream
what are the chemical substances secreted by glands called?
hormones
what is the hypothalamus-pituitary complex?
- command center of endocrine
- secrete hormones to prod. specific responses in target tissues
- regulates the synthesis and secretion of hormones of other glands
- coordinates not only messages of the endocrine but also the nervous system (nerve stimulates the command center to begin the release of hormones
what is the pituitary gland?
- called master gland
- supplies many hormones that act directly on cells or stimulate other glands that govern many vital processes
what is the posterior pituitary called and what does it produce?
neurohypophysis: nerve control by hypothalamus
ADH
- reabsorption of water by the kidney
oxytocin
- milk letdown
- uterine contractions
what is the anterior pituitary called?
adenohypophysis: hormonal control via bloodstream
ACTH
- adrenal gland, cortical hormones
FSH, LH
- sperm, testosterone, testis
- ova, estrogen, progesterone, ovary
PRL
- milk production
TSH
- thyroid hormones
MSH
- melanocytes in the epidermis, pigmentation of skin
STH
- tissue growth
what part of the pituitary gland produces the most hormones?
anterior - adenohypophysis
what is the negative feedback loop for hormones? (homeostasis)
1) imbalance - hypothalamus perceives low blood concentrations of glucocorticoids
2) hormone release - hypothalamus release corticotropin-releasing hormone (CRH) –> starts a hormone cascade that triggers the adrenal glands to release glucocorticoid into bloodstream
3) correction - blood concentration of glucocorticoids increases
4) negative feedback - hypothalamus perceives normal concentration of glucocorticoid + stops releasing CRH
how are corticosteroids released?
- hypothalamus stimulates anterior pituitary to release adrenocorticotrophic hormone (ACTH)
- signals to adrenal cortex to produce glucocorticoids, like cortisol
what to steroid hormones control?
- stress response
- BP
- blood volume
- nutrient uptake
- storage. fluid and electrolytes balance
- inflammation
what are two types of corticosteroids?
- glucocorticoids
- mineralocorticoids
about glucocorticoids?
- increase gluconeogenesis -> prod. of glucose (liver) which lead to higher blood glucose level in blood
- reduces inflammation
—> has anti-inflammatory /immunosuppressant traits
—> blocks inflammatory mediators (prostaglandins, leukotrienes)
about mineralocorticoids?
- important for water and electrolyte balance: Na+ and K+
- aldosterone hormone: increases sodium and water reabsorption (increase BP)
- increase potassium excretion
- increase fluid, increase blood volume, –> increases BP
what is Addison’s disease?
- adrenal insufficiency (hyposecretion of ACTH)
s/s: fatigue, dizziness, weight loss, muscle weakness, mood changes, darkened areas of skin
what is cushing’s disease?
- hypersecretion of ACTH
s/s: progressive obesity, skin changes, thinning of hair, moon face, buffalo hump, acne, increase body and facial hair
what is adrenal crisis?
- profound fatigue
- dehydration
- vascular collapse (dec. BP)
- renal shut down
- dec. serum Na+
- dec. serum K+
adrenal drugs: glucocorticoids
- replacement for adrenal insufficiency
-> including inflammatory (COPD, psoriasis)
-> immune system conditions (rheumatoid arthritis, IBM) - maintain water and electrolytes imbalance - much lower extent
what are common adrenal drug examples of glucocorticoids?
- prednisone -> anti-inflammatory and immunosuppressive drug
- hydrocortisone topical cream -> rashes and itching
when would corticosteroids be used to treat a disorder?
- endocrine -> adrenocortical insufficiency
- rheumatic -> rheumatoid arthritis
- collagen -> systemic lupus erythematosus
- dermatologic -> severe psoriasis
-allergic states - ophthalmic -> optic neuritis
- respiratory -> asthma, COPD
- neoplastic -> leukemia
- gastrointestinal -> ulcerative colitis
- nervous system -> MS
what hormones does the thyroid gland make?
- thyroxine (T4)
- triiodothyronine (T3)
what do the thyroid hormones do?
- dietary iodine is necessary to make TH
- TH bind to receptors inside cell, activate genes for metabolism
- control many other functions
- are referenced as metabolic hormones (influence body’s basal metabolic rate) - amt of energy used by body at rest
- nutrient breakdown and use of oxygen to produce ATP
s/s of hypothyroidism (mild)?
- pale, puffy face
- cold dry skin
- decreased metabolism
- brittle hair
- hair loss
- lethargy, fatigue
- goiter (overside thyroid gland)
what does having hypothyroidism mean?
- low thyroid function -> causes low TH levels, symptoms of slow metabolism
- thyroid works harder, goiter grows larger
