endocrine system ch12

endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

endocrine gland

a ductless gland that secretes hormones directly into the bloodstream

exocrine gland

gland that releases its secretions through tube-like structures called ducts; e.g. sweat and salivary glands

pituitary gland

endocrine gland at the base of the brain; "master gland"

hypothalamus

brain region controlling the pituitary gland

pineal gland

light-sensitive gland that secretes melatonin

melatonin

A hormone manufactured by the pineal gland that produces sleepiness.

thyroid gland

produces hormones that regulate metabolism, body heat, and bone growth

parathyroid gland

located in posterior aspect of thyroid; secretes parathyroid hormone (PTH)

thymus

Gland in the thoracic cavity above the heart where T lymphocytes mature.

adrenal glands

a pair of endocrine glands that sit just above the kidneys and secrete stress hormones

pancreas

mixed exo/edocrine gland; secretes insulin and glucagon hormones

gonads

sex glands

testes

male gonads; produce testosterone

ovaries

female gonads; produce estrogen

tropic hormones

hormones that stimulate other glands to release their hormones

follicle-stimulating hormone (FSH)

secreted by the pituitary gland to stimulate maturation of the egg or sperm cells

luteinizing hormone (LH)

secreted by the pituitary gland to promote ovulation or testosterone release

Thyroid Stimulating Hormone (TSH)

stimulates secretion from thyroid gland

Adrenocorticotropic hormone (ACTH)

Stimulates adrenal cortex to secrete stress hormones

prolactin (PL)

stimulates milk production

Growth Hormone (GH)

regulates the growth of the body

oxytocin

a hormone released by the pituitary gland that causes increased contraction of the uterus during labor and stimulates the ejection of milk during breastfeeding

antidiuretic hormone (ADH)

promotes retention of water by kidneys

thyroid hormone

this secretion stimulates cellular metabolism

calcitonin

Lowers blood calcium levels

parathyroid hormone (PTH)

raises blood calcium level

T lymphocytes

form in the thymus and other lymphatic tissue and attack cancer cells, viruses, and foreign substances

glucocorticoids

stress hormones that raise blood sugar levels

Mineralocorticoids

Promote reabsorption of Na+ and excretion of K+ in kidneys

epinephrine

aka adrenaline; a stress hormone

glucagon

A protein hormone secreted by pancreatic endocrine cells that raises blood glucose levels

alpha cells

these cells secrete glucagon

beta cells

these cells secrete insulin

insulin

A protein hormone synthesized in the pancreas that regulates blood sugar levels by facilitating the uptake of glucose into tissues

somatostatin

hormone that inhibits release of glucagon and insulin

delta cells

secrete somatostatin

gonadotropins

hormones that stimulate the testes or ovaries; FSH and LH

acromegaly

abnormal enlargement of the extremities that is caused by excessive secretion of growth hormone after puberty

gigantism

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

pituitary dwarfism

abnormally short height caused by hyposecretion of growth hormone from the pituitary gland

diabetes insipidus

hyposecretion of ADH; leads to excessive urination and thirst

corticosteroid

stress hormone; steroid hormone produced by the adrenal cortex

thyrotropin

hormone that stimulates the thyroid

adenoma

tumor of a gland

osmolality

the concentration of solutes in body fluids

endoscopic transnasal transsphenoidal approach

pituitary gland surgery done through the nose

gamma knife stereotactic radiosurgery

delivers a single high-dose radiation beam the size and shape of the tumor using special brain-imaging techniques

proton beam therapy

proton beam used to treat cancer and other tumors in the body; reduced risk of damage to surrounding tissues

external beam radiation

x-rays applied in small increments; high risk of surrounding tissue damage

somatostatin analogs

medication that reduces growth hormone secretion by pituitary tumors

bromocriptine

medication that decreases prolactin secretion by a tumor

pituitary hormone replacement therapy

multi-hormone replacement; needed after surgery or radiation therapy to maintain normal hormone levels

thyroxine

Also called thyroid hormone or T4

emaciation

abnormal thinness

hyperthyroidism

excessive activity of the thyroid gland

Graves disease

an autoimmune disorder that is caused by hyperthyroidism and is characterized by goiter and/or exophthalmos

exophthalmos

abnormal protrusion of the eyeball

goiter

enlargement of the thyroid gland

Hypothyroidism

A disorder caused by a thyroid gland that is slower and less productive than normal

myxedema

severe hypothyroidism in an adult characterized by pale dry skin, brittle hair, and sluggishness

thyroiditis

inflammation of the thyroid gland

Hashimoto's thyroiditis

an autoimmune disease in which the body's own antibodies attack and destroy the cells of the thyroid gland

cretinism

condition of congenital hypothyroidism in children that results in a lack of mental development and dwarfed physical stature

thyroidectomy

surgical removal of the thyroid gland

Hypoparathyroidism

deficient production of parathyroid hormone

tetany

prolonged, continuous muscle contraction

hyperparathyroidism

hypersecretion of the parathyroid glands, usually caused by a tumor

thyrotoxicosis

another name for hyperthyroidism

radioactive iodine therapy

use of radioactive iodine to eliminate thyroid tumors

levothyroxine

T$ replacement medication; Synthroid, Levoxyl, Levothroid

hemilobectomy

removal of one half of the thyroid gland

total thyroidectomy

removal of the entire thyroid gland

laser ablation

removal of a part using laser surgery

Antithyroid Medications

prevent formation of thyroid hormones in the gland's cells

lymphadenectomy

removal of a lymph node

radioactive iodine

therapeutic injection in order to destroy the thyroid gland

Addison's disease

adrenal glands do not produce enough of the hormones cortisol or aldosterone; adrenocortical hypofunction

Cushing's syndrome

a condition caused by prolonged exposure to high levels of cortisol; adrenocortical hyperfunction

facies

face, form, shape

Congenital Adrenal Hyperplasia (CAH)

the overdevelopment of the adrenal glands from birth

pheochromocytoma

a benign tumor of the adrenal medulla that causes the gland to produce excess epinephrine

Hyperaldosteronism

excessive output of aldosterone from the adrenal gland, leading to increased sodium and water retention and loss of potassium

androgens

male sex hormones

estrogens

female sex hormones

exocrine

secreting externally

endocrine

secreting internally

Gluconeogenesis

formation of glucose from non-carbohydrate sources

glycogenolysis

breakdown of glycogen to glucose

islets of langerhans

cell clusters in the pancreas that form the endocrine part of that organ

type 1 diabetes

disorder in which the body cannot produce enough insulin

type 2 diabetes

progressive disorder in which body cells become less responsive to insulin

insulin-dependent diabetes mellitus (IDDM)

another name for type 1 diabetes

non-insulin dependent diabetes mellitus (NIDDM)

another name for type 2 diabetes

Latent autoimmune diabetes in adults (LADA)

a condition in which type 1 diabetes develops in adults

gestational diabetes

diabetes that develops during pregnancy

Mature Onset Diabetes of the Young (MODY)

Type II diabetes caused by a single mutation in adults; not associated with obesity or high blood lipid levels

hypoglycemia

low blood sugar

hyperglycemia

high blood sugar

polyuria

excessive urination