HLTH endocrine review Flashcards
hormones affecting blood glucose levels
insulin, cortisol, epinephrine, glucagon, and GH
neurohypophysis
posterior pituitary gland
adenohypophysis
anterior pituitary gland
steroid hormones
are lipids and enter the cell to act on the nucleus to engage in transcription of mRNA
nonsteroid hormones
require a second messenger for the formation of mRNA
GH role
stimulates protein synthesis
glucagon role
increase blood glucose and stimulates glycogenolysis; released from alpha pancreatic cells
thyroxine and triiodothyronine
increase metabolic rate in all cells
what cells release insulin
beta pancreatic cells
role of insulin
promotes movement of glucose into cells
most common cause of endocrine disorders
an adenoma which is a benign tumor; this causes either a deficit or excessive amount of hormone secretion
tropic hormone meaning
hormones that have a stimulating effect on other endocrine glands
ectopic source of hormone meaning
hormones are secreted from an outside source such as in bronchogenic cancer; in these cases, levels or tropic hormones are low
what hormones are produced by the hypothalamus and then transported to the neurohypophysis?
ADH and oxytocin; these are the only 2 hormones released by the posterior pituitary gland
FSH in men
stimulates sperm production
LH in men
stimulates testosterone production
diabetes mellitus
is caused by a deficit of insulin secretion or impaired uptake of glucose by cells (insulin resistance)
anabolic hormone meaning
it synthesizes complex substances from simple molecules; insulin is an anabolic hormone
what do deficient insulin levels result in?
abnormal fat, carb, and protein metabolism because transport of amino acids and glucose into cells is impaired
what structures do not depend on glucose uptake?
the brain, digestive tract, and skeletal muscle
type I diabetes
usually develops in children but can develop in adults and results from an autoimmune issue or genetic factors; the pancreatic beta cells are destroyed and there is an absolute insulin deficiency, therefore replacement is needed
risks of diabetes
strokes, MIs, peripheral vascular disease, amputation, kidney failure, and blindness
type II diabetes
is characterized by decreased effectiveness of insulin or relative deficit of insulin and often develops later in life due to lifestyle and obesity
metabolic syndrome
common in adolescents and can lead to type II diabetes; is marked by obesity, cardiovascular changes, and significant insulin resistance due to increased adipose tissue
gestational diabetes
occurs during pregnancy but disappears after
latent autoimmune diabetes
is a slow onset of type I diabetes in adults
maturity-onset diabetes of the young
is caused by a mutation is an autosomal dominant gene
diabetes insipidus
not related to insulin but to a deficit of ADH or the kidneys do not respond to the hormone
diabetes insipidus signs
polyuria and increased thirst; dehydration may develop
polydipsia
refers to dehydration causing thirst due to insulin deficit
polyphagia
refers to stimulates appetite due to cells having a lack of nutrients resulting from insulin deficit
why does diabetic ketoacidosis occur?
a lack of glucose causing catabolism of fats and proteins, breaking fats down into fatty acids and their metabolites called ketones; ketones bind with HCO3-, decreasing the pH
what are ketones?
acetone and two organic acids (beta-hydroxybutyric acid and acetoacetic acid)
signs of diabetes
thirst, hunger, polyuria (especially at night), dry mouth, itchy skin, and blurred vision
3 P’s
polyuria, polyphagia, and polydipsia; these are the initial diabetes signs
blood level to confirm diabetes diagnosis
> 126 mg/Dl
3 tests for diabetes
the fasting blood glucose level, glucose tolerance test, and glycosylated hemoglobin test (HbA1c)
glucometer
is an at home machine used to test blood glucose levels
benefits of exercise for diabetes
exercise increase the uptake of glucose from muscles without increasing insulin use
risk of prolonged exercise
hypoglycemia
first drug of choice for type II diabetes
metformin; this reduces insulin resistance and is used when exercise and diet are not effective
why must insulin be injected?
because it will be destroyed in the GI tract if taken orally
3 types of insulin’s
rapid-onset, short acting; intermediate acting; and slow-onset, long acting
example of an intermediate acting insulin
lente
example of a slow-acting, long lasting insulin
protamine zinc or ultralente
when may insulin doses be adjusted?
infection with high fever and vomiting or surgery
when might hypoglycemia develop for those with diabetes?
following exercise, vomiting, skipping a meal, or an error in dosage
why does a lack of glucose affect the nervous system?
neurons need glucose but cannot use fats or proteins
signs of hypoglycemia
are related to impaired neurological function (lack of coordination, slurred speech, and poor concentration) and the activation of the SNS (increased pulse, pale skin, anxiety, and tremors)
what is ketoacidosis caused by?
usually infection or stress, but also may result from an error in dosage or overindulgence in foods or alcohol
signs of ketoacidosis characterization
are characterized by dehydration, acidosis, and electrolyte imbalance
dehydration signs of ketoacidosis
thirst, rough and dry oral mucosa, warm and dry skin, rapid, weak pulse, low BP, and oliguria
acidosis signs of ketoacidosis
rapid deep respirations, acetone breath, lethargy, and decreased responsiveness
Kussmaul respirations
refers to rapid, deep respirations heard in ketoacidosis
signs of electrolyte imbalances in ketoacidosis
abdominal cramping, weakness, lethargy, and nausea/vomiting
hyperosmolar hyperglycemic nonketotic coma
common in those with type II diabetes and occurs often following an overindulgence in carbohydrates, resulting in hyperglycemia and dehydration
signs of a hyperosmolar hyperglycemic nonketotic coma
neurologic defects, muscle weakness, difficulties with speech, and abnormal reflexes
3 types of macroangiopathy complications with diabetes
MI, stroke, and peripheral vascular disorder; these develop due to hypertension and hyperlipidemia
3 types of microangiopathy complications with diabetes
damage to the eyes, kidneys and nervous system; this results due to the capillary basement membrane becoming thick and hard, leading to obstruction or rupture
what causes ulcers to develop with diabetes
obstruction of the arteries in the lower limbs and this can be aggravated by peripheral neuropathy
peripheral neuropathy signs
impaired sensation, numbness, tingling, weakness, and muscle wasting
why are infections more common in diabetics?
due to vascular impairment which decreases tissue resistance, increased blood glucose levels, and decreased healing from decreased insulin
common infections in diabetics
tuberculosis, candidal infections, and periodontal disease/dental caries
why may diabetes lead to cataracts?
due to abnormal glucose metabolism that results in accumulated sorbitol and water in the lens, which may lead to blindness
how do many oral hypoglycemic drugs act?
they stimulate the pancreas to produce more insulin
tetany
muscle twitching and spasms that can be caused by hypocalcemia; first noticed in the hands and face
hypoparathyroidism causes
autoimmune, radiation or surgery in the neck, or a congenital disorder
general effects of hypocalcemia
weak cardiac muscle contraction and excitability of nerves
hyperparathyroidism causes
is caused by an adenoma, hyperplasia, or secondary to renal failure
general effects of hypercalcemia
forceful cardiac contractions and osteoporosis; also creates an increased risk for kidney stones
signs of pressure on the brain resulting from tumors
headaches, seizures, visual disturbances, and drowsiness
panhypopituitarism
cessation of pituitary function due to a tumor, resulting in loss of gonadal, thyroid, and adrenal function
dwarfism
is due to a deficit of GH or somatotropin-releasing hormone; intelligence and proportions are normal, but there is a delay is skeletal maturation and puberty
gigantism
is an excess of GH before closure of the epiphyses and puberty
acromegaly
is excess GH as an adult and is usually caused by an adenoma; soft tissues grow, bones become larger and heavier, the skull thickens, the facial features change, and the hands and feet are larger
complications of acromegaly
thickening of the skull may compress nerves and vessels, carpal tunnel syndrome, large tongue, and protruding jaw are common; this also affects glucose metabolism so there is an increased risk for diabetes; hypertension may also develop
inappropriate ADH syndrome
is due to excess ADH which results in fluid retention and signs are related to hyponatremia so are mental confusion and irritability
two thyroid hormones
thyroxine (T4) and triiodothyronine (T3)
goiter
is an enlargement of the thyroid gland which is visible on the neck; may be due to both hyperthyroid and hypothyroid issues
complications of goiters
can cause pressure on the esophagus or trachea, interfering with swallowing
endemic goiter
is a hypothyroid condition caused in certain geographical areas when there are low iodine levels in the soil and food; this causes high TSH levels, causing hyperplasia and hypertrophy in the thyroid gland
role of iodine for thyroid
is it used to synthesize T3 and T4
goitrogens
are foods that contain elements that block synthesis of T3 and T4 but increase TSH secretions, causing hyperplasia of the thyroid gland; can be cabbage, turnips, fluoride, and lithium
toxic goiter
is a hyperthyroid resulting from hyperactivity of the thyroid gland often due to increased secretions of TSH
graves disease
is a hyperthyroid condition related to an autoimmune factor, causing hypermetabolism, toxic goiter, and exophthalmos; is common in women 30+
exophthalmos
is protruding, staring eyes with decreased blinking; is a result of increased tissue mass in the eye and increased SNS stimulation; common in graves disease
thyrotoxic crisis
occurs in those with hyperthyroidism and may follow surgery or infection; causes hyperthermia, tachycardia, and delirium
general hyperthyroidism signs
tachycardia, heat intolerance, high metabolic rate, flushed and warm skin, and restlessness
general hypothyroidism signs
brachycardia, cold intolerance, low metabolic rate, pale, cool, and edema skin, and slow intellectual functions
hashimoto thyroiditis
is an autoimmune disorder and is hypothyroidism
myxedema
is characterized by thick tongue and nonpitting edema, often in the face; is a hypothyroidism condition
cretinism
is a congenital hypothyroidism disorder when the thyroid gland is absent or nonfunctional and this severely impacts growth
causes of cretinism
iodine deficiency during pregnancy or a developmental defect
signs of cretinism
delayed growth, extreme lethargy, feeding difficulties, delayed tooth eruption, and large, protruding tongue
pheochromocytoma
is a benign tumor of the adrenal medulla that causes secretions of epinephrine, norepinephrine, and other hormones; tumor originates in the sympathetic chain
signs of a pheochromocytoma
hypertension, headache, sweating, anxiety, and heart palpitations; catecholamines are also released reinforcing these
cushing syndrome
is an excess of glucocorticoids often caused by an adenoma on the adrenal medulla or posterior pituitary, an ectopic carcinoma, or large intake of glucocorticoids for medication
signs of cushing syndrome
moon face, fat on the back of the neck, muscle wasting, fragile skin, increased hair growth, osteoporosis, hypertension, and edema
complications of cushing’s syndrome
diabetes, osteoporosis, and suppression of the immune response
addison’s disease
is a deficiency of adrenocortical secretions including glucocorticoids, androgens, and mineralocorticoids; usually is caused by autoimmune conditions in which infection will destroy the adrenal gland
signs of addison’s disease
fatigue, poor stress response, decreased blood glucose levels, low BP, weight loss, hyperpigmentation, decreased body hair, and frequent infections
multiple endocrine neoplasia type I
is a rare genetic disorder caused by a gene mutation that affects endocrine glands and can cause benign tumors to develop that interfere with hormone secretion
