Chapter 11

adrenal cortex

Part of the adrenal gland that produces three mayor groups of steroid hormones called corticosteroids.

corticosteroids

Steroid hormones secreted from the adrenal cortex. The two major classes are teh mineralocorticoids and glucocorticoids. Aldosterone is the principal mineralocorticoid, and cortisol is the principal glucorcorticoid.

radioimmunoassay

Test combines radioactive chemicals and antibodies to detect minute quantities of substances in a patient's blood.

glucagon

The antagonist of insulin. Its release is stimulated by low blood glucose levels. It stimulates the liver, its primary target organ, to break down its glycogen stores to glucose and subsequently to release glucose to the blood.

testes

The male gonads, which produce sperm and secrete male sex hormones.

target organs

The organs that hormones act on to either increase or decrease the organ's activity level.

panhypopituitarism

Total pituitary impairment that brings about a progressive and general loss of hormone activity

fasting blood sugar

blood test to determine the amount of glucose int he blood after fasting for 8 to 10 hours

protein-bound iodine test

blood test to measure the concentration of thyroxine circulating in the bloodstream.the iodine becomes bound to the protein in the blood and can be measured

total calcium

blood test to measure the total amount of calcium to assist in detecting parathyroid and bone disorders

thyroid function test

blood test used to measure the levels of T3, T4, and TSH in the bloodstream to assist in determining thryroid function. (TFT)

diabetes insipidus

caused by insufficient production of the antidiuretic hormone or by the inability of the kidneys to respond appropriately to this hormone

hormones

chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

islets of Langerhans

clusters of endocrine cells that secrete two hormones directly into the circulatory system. Each islet has a population of alpha cells, which secrete the peptide hormone glucagons, and a population of beta cells, which secrete the hormone insulin.

tetany

condition affecting nerves causing muscle spasms as a result of low amounts of calcium in the blood caused by a deficiency of the parathyroid hormone

gigantism

condition brought about by overproduction of growth hormone by the pituitary gland before puberty

polyuria

condition of excessive urination

Grave's disease

condition of hypersecretion of the thyroid gland characterized by exophthalmia, tachycardia, goiter, and tumor

diabetes mellitus

condition that occurs when the pancreas produces too little insulin, resulting in an increase in the level of blood glucose

parathyroid hormone

controls the amount of calcium and phosphorus in the blood

menstrual cycle

cycle during which an egg develops and is released from an ovary and the uterus is prepared to receive a fertilized egg

hyposecretion

deficient hormone production by an endocrine gland

gynecomastia

development of mammary glands in the male caused by altered hormone levels

acromegaly

disease characterized by enlarged features, especially the face and hands, caused by hypersecretion of the pituitary hormone after puberty, when normal bone growth has stopped; most often caused by a pituitary tumor

diabetic retinopathy

disease of the retina in diabetics characterized by capillary leakage, bleeding, and new vessel formation (neovascularization) leading to scarring and loss of vision

ova

egg

endocrinopathy

endocrine system disease

goiter

enlargement of the thyroid gland

phenochromocytoma

excess production of catecholamines tumor releases catecholamines in excess increase HR BP and glucose hypertension, headache, nervousness, sweating, tachycardia, palpitations, cardiac failure

hypercalcemia

excessive calcium in the blood

hypersecretion

excessive hormone production by an endocrine gland

adrenal virilism

excessive secretion of adrenal androgens

polydipsia

excessive thirst

anterior lobe

front of body

melatonin

hormone released by the pineal gland in response to daily cycles of light and dark

glucorticoids

hormones produced by the adrenal cortex that reduce edema and the release of histamines in the respiratory system by interrupting the inflammatory process.

myxedema

hypothyroidism marked by dry skin and swellings around lips and nose as well as mental deterioration

adrenalitis

inflammation of an adrenal gland

androgens

influence development and maintenance of male sex characteristics, for example, facial hair, deep voice

adrenal medulla

inner part of adrenal gland; secretes epinephrine and norepinephrine

chemical thyroidectomy

large dose of radioactive iodine is given in order to kill thyroid gland cells without having to actually do surgery

thymus glands

large elongated masses extending from the throat region down over the cranial portion of the heart

thyroid gland

large gland in the front of the neck, it secretes hormones which regulate growth and metabolism

pineal gland

located in the center of the brain, functioning to secrete melatonin and serotonin

ovaries

located one on each side of the uterus in the female pelvis, functioning to secrete estrogen and progesterone

pancreas

located partially behind the stomach in the abdomen, and it functions as both an endocrine and exocrine gland. It produces digestive enzymes as well as insulin and glucagon

hypocalcemia

low calcium in the blood

homeostasis

metabolic equilibrium actively maintained by several complex biological mechanisms that operate via the autonomic nervous system to offset disrupting changes

obesity

more than average fatness

Addison's disease

occurs when the adrenal glands do not produce enough of the hormones cortisol or aldosterone

ketoacidosis

presence of an abnormal amount of ketone bodies in the blood and urine indicating an abnormal utilization of carbohydrates as seen in uncontrolled diabetes and starvation

exophthalmos

protrusion of one or both eyeballs, often because of thyroid dysfunction or a tumor behind the eyeball

exocrine glands

release their secretions through ducts or tubes onto a body surface or into a cavity. ex. sweat, salivary or tear glands

adrenalectomy

removal of adrenal glands

thyroidectomy

removal of the thyroid

gametes

reproductive cells, have only half the number of chromosomes as body cells

gonads

reproductive glands-male, testes; female, ovaries

cortisol

secreted from the adrenal cortex, aids the body during stress by increasing glucose levels and suppressing immune system function

cretinism

severe hypothyroidism resulting in physical and mental stunting

endocrinologist

specialist in the endocrine system

hypothyroidism

state of deficient thyroid gland activity

hyperthyroidism

state of excessive thyroid

glycosuria

sugar in the urine

lobectomy

surgical removal of a lobe from any organ of the body (as the lung or brain)

edema

swelling from excessive accumulation of serous fluid in tissue

thyroid scan

test in which a radioactive iodine is administrated that localizes in the thyroid gland. the gland can then be visualized with a scanning device to detect pathology such as tumors

glucose tolerance test

test that measures the body's ability to metabolize carbohydrates by administering a standard dose of glucose and measuring glucose levels in the blood and urine at regular intervals

circadian rhythm

the biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle.

thalamus

the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

endocrinology

the branch of medicine dealing with the endocrine glands and their secretions

pituitary gland

the master gland of the endocrine system

hormone replacement therapy

the use of the female hormones estrogen and progestin to replace those the body no longer produces during and after perimenopause

parathyroid glands

there are four and they are embedded in the surface of the thyroid, function in the homeostasis of calcium ions. They secrete Parathyroid hormone (PTH), which raises blood levels of calcium and thus has an effect opposite to that of the thyroid hormone calcitonin.

thyrotoxicosis

toxic condition due to hyperactivity of the thyroid gland

thyroid echogram

ultrasound examination of the thyroid that can assist in distinguishing a thyroid nodule from a cyst

aldosterone

"salt-retaining hormone" which promotes the retention of Na+ by the kidneys. na+ retention promotes water retention, which promotes a higher blood volume and pressure

blood serum test

Blood test to measure the level of substances such as calcium, electrolytes, testosterone, insulin, and glucose. Used to assist in determining the function of various endocrine glands.

dwarfism

Condition caused by insufficient growth hormone in childhood

adrenal feminization

Development of female secondary sexual characteristics (such as breasts) in a male; often as a result of increased estrogen secretion by the adrenal cortex.

endocrine glands

Ductless glands that empty their hormonal products directly into the blood

hirsutism

Excessive growth of body hair in females

insulin

Hormone produced by the pancreas that is released when stimulated by elevated glucose levels. This hormone decreases blood sugar levels by accelerating the transport of glucose into the body cells where it is oxidized for energy or converted to glycogen or fat for storage.

steroid sex hormones

Include estrogens, progestins, and androgens Produced by the gonads in response to signals from Hypothalamus Pituitary

sperm

Male sex cell

insulin-dependent diabetes mellitus

Occurs when antibodies bind insulin-secreting cells of the pancreas, eventually reducing the body's ability to produce insulin.

mineralocorticoids

One of the major groups of steroid hormones produced by the adrenal cortex. It regulates water and electrolyte balance in extracellular flid, mainly by regulatind sodium reabsorption by the kidney tubules. Chiefly aldosterone.

epinephrine

adrenaline; activates a sympathetic nervous system by making the heart beat faster, stopping digestion, enlarging pupils, sending sugar into the bloodstream, preparing a blood clot faster

posterior lobe

back of body

glands

A cell, a group of cells, or an organ that produces a secretion for use elsewhere in the body or in a body cavity or for elimination from the body.

progesterone

A hormone produced by the ovaries which acts with estrogen to bring about the menstral cycle.

growth hormone

A hormone released by the anterior pituitary that targets all cells in the body. Growth hormone stimulates whole body growth in children and adolescents, adn increases cell turnover rate in adults.

calcium

A mineral that is essential for bone growth, teeth development, blood coagulation, and many other functions

luteinizing hormone

A protein hormone secreted by the anterior pituitary that stimulates ovulation in females and androgen production in males.

insulinoma

a benign tumor of the pancreas that causes hypoglycemia by secreting additional insulin

norepinephrine

a catecholamine precursor of epinephrine that is secreted by the adrenal medulla and also released at synapses

adrenaline

a catecholamine secreted by the adrenal medulla in response to stress (trade name Adrenalin)

estrogen

a general term for female steroid sex hormones that are secreted by the ovary and responsible for typical female sexual characteristics

Cushing's syndrome

a group of signs and symptoms associated with hypersecretion of the glucocorticoids by the adrenal cortex

syndrome

a group of symptoms or signs that collectively characterize or indicate a disease, disorder, abnormality, etc.

somatotropin

a hormone produced by the anterior pituitary gland

adenocarcinoma

a malignant tumor that originates in glandular tissue

laparoscopic adrenalectomy

a minimally invasive procedure to surgically remove one or both adrenal glands

hypothalamus

a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion

peripheral neuropathy

a painful condition of the nerves of the hands and feet due to damage to the peripheral nerves; also known as peripheral neuritis

adrenal glands

a pair of endocrine glands just above the kidneys. the adrenals secrete the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline), which help to arouse the body in times of stress.

acidosis

abnormally high acidity (excess hydrogen-ion concentration) of the blood and other body tissues