Chapter 13 Endocrine System Key Terms

hormones

chemical messengers that are secreted by endocrine glands directly into the bloodstream

ACTH

stimulates the growth and secretions of the adrenal cortex

FSH

stimulates the secretion of estrogen and growth of ova in ovaries; stimulates sperm production

GH; somatotropic hormone

regulates growth of bone, muscle, and body tissues (give abbreviation and other name)

lactogenic hormone (LTH); prolactin

stimulates and maintains production of breast milk in the mother after childbirth (give name, abbr, and other name)

LH

stimulates ovulation in the female and the secretion of testosterone in males

MSH

increases the production of melanin in melanocytes, thereby causing darkening of skin pigmentation; usually increases during pregnancy

TSH

stimulates the secretion of hormones by the thyroid gland

ADH; vasopressin

one of the few hormones secreted by the posterior hypophysis; increases blood pressure by reducing the amount of water excreted thru the kidneys and maintaining it in the blood stream (give abbr and alternate name)

diuretic

medication administered to increase the amount of urine secretion

oxytocin

one of the few hormones secreted by the posterior hypophysis; stimulates uterine contractions during childbirth, controls postnatal hemorrhages, and stimulates the flow of milk from the mammary glands

pitocin

synthetic form of oxytocin that is administered to induce or speed up labor

melatonin

hormone that influences the sleep-wakefulness portions of the circadian cycle

T₄

inactive thyroid hormone; gets converted into T₃ which regulates metabolism

T₃

active thyroid hormone; increases metabolic rate or the rate at which the body uses nutrients

TSH

hormone that controls the secretion of T₃ and T₄

calcitonin

hormone that works with PTH to decrease calcium levels in the blood and tissues by moving calcium into storage in the bones and teeth

PTH

works with calcitonin to increase calcium levels in the blood and tissues by releasing calcium stored in bones and teeth

thymus

gland that secretes thymosin that functions as part of the immune system before birth and in childhood; its function is greatly reduced after puberty and slowly turns into fatty tissue

thymosin

secreted by the thymus to stimulate the maturation of lymphocytes into T cells

pancreatic islets

the parts of the pancreas that have endocrine functions whose function are to control the blood glucose levels and glucose metabolism throughout the body

glucose, glucagon, insulin

the three secretions of the pancreatic islets

glucagon

hormone secreted by the pancreas’s alpha cells in response to low levels of glucose in the bloodstream; increases glucose levels by stimulating the liver to convert stored glycogen into glucose for release into bloodstream

insulin

hormone secreted by the pancreas’s beta cells in response to high levels of glucose in the bloodstream; allows glucose to enter cells to be used as energy and stimulates the liver to convert additional glucose into glycogen for storage

electrolyte

One of the primary functions of the adrenal glands is to control ____ levels within the body as well as regulating metabolism and interacting with the sympathetic nervous system in response to stress

electrolytes

mineral substances—calcium, chloride, magnesium, phosphorus, sodium, and potassium—that are normally found in the blood and other bodily fluids

androgens, corticosteroids (aldosterone and cortisol)

secretions of adrenal cortex

corticosteroids

steroid hormones produced by the adrenal cortex; the two main types are aldosterone and cortisol

aldosterone

a corticosteroid that regulates the sodium and water levels in the body by increasing sodium and water reabsorption and potassium excretion by the kidneys

cortisol; hydrocortisone

a corticosteroid that has an anti-inflammatory action and regulates the metabolism of carbs, fats, and proteins; increases blood sugar to provide immediate energy by stimulating glucose production in the liver (give usual name and alternate name)

epinephrine and norepinephrine

secretions of the adrenal medulla

epinephrine

stimulates the sympathetic nervous system in response to physical injury or to mental stress (heart beats faster and blood pressure rises; liver releases glucose and limits release of insulin)

norepinephrine

both a hormone and neurohormone; plays an important role in the “fight-or-flight response” by raising blood pressure, strengthening the heartbeat, and stimulating muscle contractions

estrogen

a hormone secreted by the ovaries for the development and maintenance of female secondary sex characteristics and regulation of the menstrual cycle

progesterone

hormone released during second half of the menstrual cycle to complete the preparation of the uterus for possible pregnancy

androgens

sex hormones, primarily testosterone, secreted by gonads, adrenal cortex, and fat cells to promote and maintain male sex characteristics

steroids

a family of hormones derived from cholesterol; can be made by the body (testosterone, estrogen, cortisol) or artificial

anabolic steroids

man-made substances that are chemically related to male sex hormones and are used in the treatment of hormone problems in men and help replace muscle mass lost to disease

leptin

hormone secreted by fat cells that is involved in the regulation of appetite by suppressing it and begin burning stored fat in adipose tissue

ghrelin

a hormone produced in the GI tract that stimulates hunger and promotes fat storage

neurohormones

hormones produced and released by neurons in the brain, rather than by endocrine glands

acromegaly

hormonal disorder characterized by abnormal enlargement of the extremities caused by excessive secretion of GH after puberty

gigantism

abnormal growth of the entire body that is caused by excessive secretion of GH before puberty

hyperpituitarism

excess secretion of GH that causes both acromegaly and gigantism; usually caused by a pituitary adenoma

hypopituitarism

condirion in which the pituitary gland does not produce enough GH; one of the causes of short stature (dwarfism)

pituitary adenoma

also known as a pituitary tumor; a slow-growing benign tumor of the pituitary gland; functional pituitary tumors often produce hormones in large, unregulated amounts such as ACTH, GH, or TSH

galactorrhea

condition in which an excess of prolactin causes the breasts to produce milk spontaneously, not due to childbirth

prolactinoma

benign functional pituitary tumor that causes the pituitary gland to produce too much lactogenic hormone (prolactin); can cause infertility in women, ED in men, and impair vision

diabetes insipidus

disorder caused by an insufficient production of ADH or by the inability of the kidneys to respond appropriately to ADH, causing an imbalance of fluids in the body and leading to extreme thirst and frequent urination

syndrome of inappropriate ADH secretion

caused by the overproduction of ADH; often the result of cancer or its treatment; high amount of ADH keep the kidneys from excreting water, resulting in bloating and water retention that can dilute the blood, causing electrolyte imbalances like hyponatremia (low levels of sodium)

pinealoma

a tumor of the pineal gland that can disrupt the production of melatonin; can cause insomnia by disrupting the circadian cycle

thyroid carcinoma

the most common cancer of the endocrine system and the most rapidly increasing cancer in the US; affects women more than men, usually diagnosed between ages 20-55

hypothyroidism

marked by a deficiency of thyroid secretion with symptoms like fatigue, depression, sensitivity to cold, and decreased metabolic rate

Hashimoto’s disease

an autoimmune disease in which the body’s own antibodies attack and destroy the cells of the thyroid gland, leading to hypothyroidism

cretinism

a congenital form of hypothyroidism where if thyroid hormone replacement is not started soon after birth, this disorder causes arrested physical and mental development

myxedema

also known as adult hypothyroidism; severe form of hypothyroidism characterized by puffy skin and swelling of laryngeal and pharyngeal mucous membranes

thyrotoxicosis

alternate name for hyperthyroidism; the overproduction of thyroid hormones which causes an imbalance of increased metabolism, sweating, nervousness, and weight loss; most common cause of Grave’s disease

Grave’s disease

disorder of unknown cause in which the immune system attacks the thyroid gland and its antibodies mimic TSH, stimulating it to make excessive amounts of thyroid hormones; results in hyperthyroidism, goiter, and exophthalmos

goiter; thyromegaly

an abnormal, benign enlargement of the thyroid gland, producing a swelling in the front of the neck; usually occurs due to conditions causing hyperfunction or hypofunction of the gland such as iodine deficiency, Grave’s, Hashimoto’s, and thyroiditis (2 names)

exophthalmos

abnormal protrusion of the eyeball out of the orbit caused by hyperthyroidism

thyroid storm; thyrotoxic crisis

an acute life-threatening condition caused by exaggerated hyperthyroidism with fever, chest pain, palpitations, shortness of breath, increased disorientation, and fatigue

hyperparathyroidism

overproduction of the parathyroid hormone and causes the condition known as hypercalcemia; can result from a disorder of the parathyroid gland or elsewhere like a kidney failure

hypoparathyroidism

caused by insufficient secretion of the parathyroid hormone; causes hypocalcemia and, in severe cases, tetany

tetany

the condition of periodic, painful muscle spasms and tremors due to hypocalcemia making nerves unstable and prone to firing spontaneous signals to the muscles

hypercalcemia

abnormally high concentrations of calcium in the bloodstream; can lead to weakened bones and formation of kidney stones

hypocalcemia

abnormally low levels of calcium in the bloodstream

myasthenia gravis

this chronic autoimmune neuromuscular disorder can be characterized by an abnormally large thymus, sometimes having a tumor

insulinoma

a benign tumor of the pancreas that secretes additional insulin, causing hypoglycemia (low blood glucose)

pancreatitis, alcohol abuse

____ is inflammation of the pancreas with ____ ____ as its leading cause

hyperglycemia

abnormally high concentration of glucose in the blood; primarily seen in patients with diabetes mellitus; symptoms include polydipsia, polyphagia, and polyuria

polydipsia

excessive thirst

polyphagia

excessive hunger

polyuria

excessive urination

hyperinsulinism

condition of excessive secretion of insulin in the bloodstream, causing hypoglycemia

hypoglycemia

an abnormally low concentration of glucose in the blood with symptoms like nervousness and shakiness, confusion, perspiration, or feeling weak

diabetes mellitus

What is the most common endocrine system disease?

diabetes mellitus

a group of metabolic disorders characterized by hyperglycemia resulting from defects in the body’s production of insulin (type 1) or its ability to use it properly (type 2); not related to diabetes insipidus; classified as type 1, type 2, and latent autoimmune diabetes

type 1 diabetes; insulin-dependent diabetes mellitus (IDDM)

autoimmune insulin deficiency disorder caused by the destruction of pancreatic islet beta cells where they don’t secrete enough insulin; symptoms include polydipsia, polyphagia, polyuria, weight loss, blurred vision, and extreme fatigue (2 names and abbr)

type 2 diabetes; non-insulin-dependent diabetes mellitus (NIDDM)

diabetes mellitus in which insulin production may be normal, but the body cannot use the insulin effectively nor can it increase insulin production sufficiently to compensate (2 names and abbr)

prediabetes

condition in which the blood glucose level is higher than normal, but not high enough to be classified as type 2 diabetes; indicates an increased risk of NIDDM, heart disease, and stroke

latent autoimmune diabetes in adults (LADA)

a condition in which type 1 diabetes develops in adults (name and abbr)

gestational diabetes mellitus (GDM)

form of diabetes mellitus with onset occuring around the 24th week of some pregnancies; resolves itself after delivery but women with these have increased risk of developing NIDDM

diabetic coma

a diabetic emergency caused by extreme hyperglycemia or hypoglycemia resulting in a stupor or coma; causes a person to become unconscious and can be fatal if untreated

diabetic ketoacidosis

a life-threatening complication of diabetes in which the body produced acidic ketone bodies as a result of hyperglycemia

severe hypoglycemia; insulin shock

shock caused by hypoglycemia, usually due to an injection of too much insulin or failure to eat after an injection

diabetic retinopathy

diabetic complication where diabetes damages the capillaries in the retina, causing blood to leak into the posterior segment of the eyeball and produces the damage that causes the loss of vision

ketosis

a normal metabolic process that helps the body utilize stored fat when other sources of energy are lacking; an excessively high level of this may indicate that the body isn’t producing enough insulin to convert glucose into energy

adrenalitis

most common cause of Addison’s disease

aldosteronism

an abnormality of the electrolyte balance that is caused by the excessive secretion of aldosterone; bodyprimary symptom is hypertension

Addison’s disease

disease resulting from insufficient secretion of cortisol and sometimes aldosterone; characterized by progressive anemia, hypotension, hypoglycemia, increased skin pigmentation, joint pain, and loss of appetite

Cushing’s syndrome; hypercortisolism

condition resulting from hypersecretion of cortisol; may be caused by a tumor or prolonged use of corticosteroids; characterized by weakness, thin and easily bruised skin, hypertension, weight gain, and a flushed and rounded face

hypergonadism

condition of excessive secretion of hormones by the gonads, causing early onset of puberty and increased sex drive

hypogonadism

more common that hypergonadism; condition of deficient secretion of hormones by the gonads; can lead to ED, low sperm count, decreased sex drive, and infertility

gynecomastia

condition of excessive mammary development in the male; caused by an increase in male estrogen levels or a decrease in testosterone

radioactive iodine reuptake test (RAIU)

a test that uses radioactive iodine administered orally to measure thyroid function; the amount of radioactivity in the thyroid is measured later

TSH assay

a diagnostic test to measure the circulating blood level of TSH; used to detect abnormal thyroid activity resulting from excessive pituitary stimulation

fasting blood sugar (FBS) test; fasting plasma glucose test

diagnostic test that measures the blood glucose levels after the patient has not eaten for 8 to 12 hours to screen for diabetes

oral glucose tolerance test (OGTT)

most commonly performed test to diagnose type 2 or gestational diabetes; after fasting for 8 hours, the patient, the patient has a baseline blood draw then drinks a very sugary liquid so that blood glucose concentration is measured repeatedly for a few hours

home blood glucose monitoring

measures the current glucose level using a drop of blood and is often performed by the patient multiple times a day

continuous glucose monitoring (CGM)

a method of tracking glucose levels 24 hours a day through a tiny sensor inserted under the skin on the abdomen or arm; it measures glucose levels in your cellular fluid below the skin and alerts when glucose levels are too high or low