Repro Flashcards
hormone
any substance secreted by glandular tissue in the body which stimulate a specific physiological response in cells or activate certain tissues
endocrine
referring to glands that secrete hormones and other substances INTO the body (central circulation)
exocrine
referring to glands that secrete hormones and other substances OUTSIDE the body (into the GI tract, onto the skin)
catecholamine
an organic compound that functions like a neurotransmitter; can occur outside the CNS - specifically EPI, NE, DA
corticosteroid
any steroid type hormone produced by the adrenal cortex; ‘steroids’
Components of the Endocrine System (8)
Hypothalamus/pituitary gland
pineal gland
thyroid
parathyroid
thymus
adrenal glands
pancreas
gonads
Hypothalamus and Pituitary Gland components
anterior and posterior hypophysis
adrenal gland parts
cortical and medullary
Male and female gonads
M - testes
F - ovaries
Pituitary lobe
endocrine extension of hypothalamus: ‘master regulator,’ links the CNS to systemic endocrine function
anterior and posterior lobes
anterior pituitary gland secretions
secretes GH, tropic hormones, prolactin, ACTH, TSH, FSH, and LH
Anterior pituitary regulation
growth rate, sexual maturation, metabolism, stress response, metabolism, fluid balance
Anterior pituitary gland tumor rate
1 in 5 patients with intercranial tumors present with a pituitary tumor
Growth hormone (GH; HGH) primary function
growth regulation during childhood and puberty
GH; HGH
- HGH levels are mediated by hypothalamic signaling
- HGH released daily; metabolically important to growth of peripheral tissues (HGH synthesis increases after 18 mo; greatest levels during puberty, steadily declines > about 40 yrs old)
- HGH essential for normal growth/development (deficiency in childhood/puberty results in growth deficits)
GH; HGH opposes and stimulates what
- opposes activity of insulin
- stimulates gluconeogenesis + glycogenolysis
- acute phase reactant in stress/illness states
ACTH -> adrenocorticotropic hormone primary function
regulates the release of cortisol and other corticosteroids and androgens
ACTH signaled by. . .
the hypothalamus by CRH (corticosteroid releasing hormone)
ACTH -> augmenting metabolism and euvolemic fluid balance. . .
- cortisol and glucocorticoids 1) increase blood sugar, 2) induce catabolism of proteins and fats, 3) cause bone reabsorption
ACTH -> help increase muscle/bone mass, critical role in male secondary sex characteristics. . .
- spermatogeneis and testicular development
- testicular androgen production
Thyroid stimulating hormone (thyrotropin; TSH) primary function
control the release of thyroxine (T4) from the thyroid. helps decrease triiodothyronine (T3) to a lesser degree
TSH
- neg feedback loop btwn TRH, TSH, and T4
- TSH is not an ‘active thyroid hormone;’ T4 and T3 are
- as more TSH binds to TSH receptors in the thyroid, more active thyroid hormone is released (`80% as T4, 20% T3)
- iodine intake and utilization is necessary for normal thyroid and thyrotropic function
Follicle stimulating hormone; FSH
- primarily responsible for the initiation of the menstrual cycle
- stimulates the maturation of follicular oocytes in the ovaries
- men; lower levels of FSH help maintain/control spermatogenesis
Luteinizing hormone -> LH
- LH levels rise in females to stimulate ovarian production of estradiol
- peak after ~14 days in tandem with a surge in FSH -> causes ovulation
- after ovulation; the ovarian follice forms a corpus luteum, can make progesterone if implantation occurs
- men; lower levels of FSH stimulate the testes to produce testosterone
Posterior pituitary gland
- secretes ADH, oxytocin
- ADH (vasopressin) stimulates the formation of aquaporins in the renal tubules -> resorption of soulte-free water
- oxytocin: important neurotransmitter, ‘let down,’ uterine contractility
anti-diuretic hormone (vasopressin)
- reduces renal secretion
- causes retention of free water and sodium
- secretion stimulated by angiotensin 2
Oxytocin
- stimulates contraction of uterine smooth muscle, facilitates normal childbirth
- stimulates smooth muscle of mammary glands, allows for mechanical ‘let down’ of breast milk
- different effects within the CNS: associated with bonding, trust, familial association, romantic dyads
pineal gland
- small, cone-shaped organ in the epithalamus (mid brain), not isolated in the BBB
- evolutionary, an atrophied photo-receptor (receives info from optic ganglia, knows when it is getting dark)
Pineal gland secretes. .
- melatonin based on the circadian rhythm information
- helps to induce somnolence; regulates sleep-wake cycle
thyroid gland
T3 and T4 (thyroxine)
- regulate metabolic activity
- cellular division and tissue growth
- caloric consumption and BMR
- organ system activity and responsivity
T4>T3 in terms of regulatory function
too much = hypermetabolic state
too little = hypometabolism
Parathyroid gland
- PTH or parathormone
- essential regulator of calcium balance
- hypocalcemia stimulates the parathyroid gland to secrete PTH -> increases the activity of osteoclasts in bone tissue (more clacium and phosphorous available in serum)
Adrenal gland
- cortex (bark), and medulla (marrow)
- mineralcorticoids: primarily influence salt balance
- glucocorticoids: influence blood sugar regulation
Corticosteroids used for. . .
suppress inflammation
Corticosteroids examples
-one, prednisone, dexamethasone, hydrocortisone
Corticosteroids
- potent anti-inflammatory action suppresses inflammatory cascade at mx sites, sometimes given for other dx
- multiple routes
- shortest tx period; lowest dose
- watch for side effects
- client education very important
Corticosteroid side effects
- weight gain (esp centrally)
- fluid retention and edema (esp in the facial region)
- elevated blood sugar and sodium levels
- thinning skin and brittle bones
- stomach irritation and gastric ulcers
- mood changes - irritability, insomnia
Pancreas
- retroperitoneal glandular organ adjacent to the stomach
- inserts into the duodenum via the ampulla of vader
- endocrine and exocrine
- endocrine function = Isle of Langerhans
Which pancreas cells secrete glucagon?
alpha cells
which pancreas cells secrete insulin?
beta cells
insulin
- naturally secreted by the pancreas after we eat (postprandially)
- allows glucose to enter cells; driving blood sugar levels
- insulin also causes intracellular potassium shift; can result in relative hypokalemia
glucagon
- hormone, stimulates glycogenolysis and glyconeogenesis
- not a sugar or a carb
- levels are reciprocally proportional to blood sugar levles
- glucagon for when the glucose is gone
glycogenolysis
break down of storage form of glucose in the liver - glycogen
gluconeogenesis
making new glucose molecules
estrogen
primary group of hormones responsible for female secondary sex characteristics
- repro development; menarche (menstruation cycle), pubescent changes
- thelarche (breast development), bone development and bone density
progesterone
hormone that is instrumental in menstruation and pregnancy, helps facilitate embryogenesis
- promotes blood flow to the uterine lining -> allows for importation of fertilized egg
- promotes placental blood flow; helps maintain the early stages of pregnancy
testosterone
androgen
primary group of hormones responsible for male secondary sex characteristics
- reproductive development: penile/scrotal growth, spermarche (sperm production), pubescent changes
- increased lean muscle mass (anabolic effect)
Dihydrotestosterone (DHT)
chemically derived from testosterone; the most potent hormone among the androgens
- promotes maturation of the prostate and seminal vesicles; fertility factor
- as males age -> drives prostatic hypertrophy (BPH) and male pattern baldness
pituitary gland goal
replacement therapy
pituitary gland MOA
- augment or antagonize the natural effects of the pituitary hormone
- exogenously given corticotropin elicits the same response as ACTH
Cosyntropin
- pituitary gland
- travels to the adrenal cortex and stimulates secretion of cortisol
- used for adrenalcortical insufficiency
Somatropin
- pituitary gland
- synthetic drugs that mimics growth hormones through various processes
Octreotide
- pituitary gland
- antagonizes the effects of GH
Vasopressin
- pituitary gland
- used to prevent and control polydipsia, polyuria, and dehydration with diabetes insipidus (DI)
thyroid hormones
- T4, thyroxine
- T3, triiodothyronine
- TSH, thyroid stimulating hormone
thyroid replacement drugs natural and synthetic
natural: thyroid
synthetic: levothyroxine (chemically pure and more predictable)
thyroid replacement drugs MOA
- should be taken before food, at the same time every morning
- works in the same manner as endogenous thyroid hormones, effecting many body systems
- works to induce change in the metabolic rates, increased O2 consumptions, and body temperatures
- increases beta-adrenergic receptors, making the heart more sensitive to catecholamines, increases CO
anti-thyroid drugs goal
treat underlying disease, like hypothyroidism, Grave’s, cancer
anti-thyroid drugs examples
iodides, ionic inhibitors, radioactive isotopes of iodine
- thioamide derivatives: methimazole and propylthiouracil (PTC)
anti-thyroid drug MOA
- inhibit the incorporation of iodine molecules into the amino acid tyrosine (a process required to make the precursors of T3 and T4). Impedes the formation of thyroid hormone.
- PTU inhibits the conversion of T4 to T3 in peripheral circulation
- neither drug can inactivate existing thyroid hormone
adrenal medulla
epi and norepi
adrenal cortex
- corticosteriods, glucocorticosteriods, mineralcorticoids (regulates electrolytes) (aldosterone, helps control Na+/K+ balance)
adrenal gland over secretion + drug example
cushing’s, adrenal crisis
Osilodrostat
adrenal gland under secretion + drug examples
addison’s disease
hydrocortisone, prednisone, prednisolone, dexamethasone. Exclusive mineralcorticoid activity: fludrocortisone
Adrenal drugs MOA, SE, and indications
MOA
- under secretion
- r/t to their involvement with synthesis of specific
- effects fluid and water retention
- inhibit inflammatory and immune response
SE
- many
Indications
-many
pancreas
exocrine gland, secreting digestive enzymes through the pancreatic ducts, and an endocrine gland, secreting hormones into the bloodstrem
2 pancreas hormones
- insulin
- glucagon
glucose definition
primary source of energy for cells
glycogen definition
the stored excess of glycose in the liver (mostly), until it is needed
glycogenolysis definition
conversion of glycogen back into glucose
Rapid insulin example and pharmacokinetics
-SQ
- Insulin Lispro
- onset = 15 minutes
- peak = 1-5 hours
- duration = 3-5 hours
Short acting insulin example and pharmacokinetics
- SQ
- regular insulin
- onset: 30-60 minutes
- peak: 2.5 hours
- duration: 6-10 hours
long acting insulin example and pharmacokinetics
- SQ
- insulin glargine
- onset: 1-2 hours
- no peak
- duration: 24 hours
intermediate insulin example and pharmacokinetics
- SQ
- NPH
- onset: 1-2 hours
- peak: 4-8 hours
- duration: 10-18 hours
Insulin MOA
- replaces the insulin either not made or made defectively
- restores the ability to metabolize carbs, fats, and proteins
- allows glucose to be stored in the liver
- helps convert glycogen to fats
- does NOT reverse defects in insulin receptor sensitivity
insulin adverse effects
hypoglycemia
Basal-Bolus Insulin Therapy
- preferred tx method
- attempting to mimic a healthy pancreas by delivering long-acting insulin constantly )basal) and giving rapid/short acting insulin when glucose levels rise (like with food)
sliding slide insulin tx plan
- used to “correct” elevated blood glucose levels
- helpful when BG levels are elevated due to stress, infx, etc
biguanides example and MOA
- ex: metformin (first line drugs and commonly used for DM2)
MOA - decrease glucose production by the liver
- decreases intestinal absorption of glucose and improve insulin receptor sensitivity
-> increased peripheral glucose uptake and use, decreased hepatic production of triglycerides and cholesterol
sulfonylureas ex and MOA
- ex: glipizide, glyburide, and glimepiride
MOA - bind to specific receptors on beta cells in the pancreas to stimulate the release of insulin
- decrease the secretion of glucagon
- pt must have functioning cells in the pancreas
Glinides ex, MOA, indication, and contraindications
- ex: repaglinide, nateglinde
MOA - increase insulin secretion from the pancreas
- very short duration and must be given with each meal
- indication: DM2
- contraindications: can’t take with sulfonylureas
thiazolidinediones (glitazones) ex and MOA
- ex: pioglitazone
MOA - decrease insulin resistance by enhancing the sensitivity of insulin receptors
- directly stimulate peripheral glucose uptake and storage
- inhibits glucose and triglyceride production in the liver
- slow onset (several weeks-months for benefit)
alpha-glucosidase inhibitors ex and MOA
- ex: acarbose and miglitol
MOA - inhibits enzyme alpha-glucosidase in the sm intestine
- this enzyme normally is responsible for hydrolysis of oligosaccharides and disaccharides to glucose
- when blocked: glucose absorption is delyaed
- timing is important: must be taken with meals
sodium glycose cotransporter inhibitors (SGLT2)
- glucose is reabsorbed into circulation but SGLT, which transport Na+ and glucose into cells
- inhibition of SGLT2 leads to a decrease in blood glucose and an increase in renal glucose secretion
female replacement hormones
- estrogen
- progesterone
estrogen ex and MOA
- ex: estradiol transdermal, estradiol cypionate, estradiol valerate, ethynyl estradiol
MOA - steroidal and nonsteroidal (in the US, only have steroidal)
- the binding of estrogen to intracellular estrogen receptor stimulates the synthesis of nucleic acids and proteins
- produces effects in estrogen-responsive tissue receptors
progesterone ex, MOA, and indications
- ex: hydroxyprogesterone, pregnenolone, medroxyprogesterone, norethindrone, megestrol
MOA - most active pro-gestational hormone
- produced after ovulation by the corpus luteum and during pregnancy by the placenta
- indications: hormonal imbalance, fibroids, uterine cancer, amenorrhea, contraception, helps prevent threatened miscarriage
contraception ex, MOA, SE
- note: oral contraception does not protect against STD/STI
- ex: estrogenic, pregestational steroids
MOA - prevents ovulation
- inhibits the release of gonadotropins
- increases uterine mucous viscosity
- decreased sperm movement and fertilization of the ovum
- inhibits implantation of fertilized egg
- SE: HTN, thromboembolism (increased risk with smoking)
fertility drugs and MOA
- ex: clomiphene (clomid)
MOA - blocks estrogen receptors in the uterus and brain -> a fake signal of low estrogen levels is sent to the brain
- increased the production of GNRH (from the hypothalamus), FSH and LH (from the pituitary gland) -> stimulates maturation of the ovarian follicles -> ovulation
uterine stimulation: ergot derivatives
during pregnancy, the uterus is sensitive to oxytocin
uterine stimulation: prostaglandins
during childbirth, it stimulates uterine contraction
uterine stimulation: progesterone antagonist mifepristone
aids in lactation
Uterine stimulation: oxytocin
regulates smooth muscles in the uterus
androgens ex, MOA, SE
- ex: methyltestosterone, fluoxymesterone
- note: oral testosterone has a significant first pass effect
MOA
- stimulates normal growth and development of male sex organs
- development and maintenance of secondary sex characteristics
- helps retain nitrogen which has important metabolic roles
- SE: weight gain
androgen inhibitor: benign prostatic hyperplasia (BPH)
- androgen inhibitors blocks the effects of naturally occurring endogenous androgens
- ex: finasteride and dutasteride
androgen inhibitors: prostate cancer
- blocks activity of androgen hormones at the receptor level
- ex: flutamide, nilutamide, and bicalutamide
