Endocrine System Vocabulary

Goiters

A goiter is an enlargement of the thyroid gland that results when the diet is deficient in iodine.

Atrial Natiuretic Peptide (ANP)

A hormone released by the heart, atrial natriuretic peptide (ANP), prevents aldosterone release, its goal being to reduce blood volume and blood pressure.

Adrenocorticotropic Hormone (ACTH)

Adrenocorticotropic Hormone (ACTH) regulates the endocrine activity of the cortex portion of the adrenal gland.

Melatonin

Although many chemical substances have been identified in the pineal gland, only the hormone melatonin appears to be secreted in substantial amounts. Melatonin is believed to be a "sleep trigger" that plays an important role in establishing the body's day-night cycle.

Amino Acid-Based Molecules

Although many different hormones are produced, nearly all of them can be classified chemically as amino acid-based molecules.

Gonads

An organ that produces gametes; a testis or ovary.

Ductless Glands

Both endocrine and exocrine glands are formed from epithelial tissue, but the endocrine glands are ductless glands that produce hormones that they release into the the blood or lymph.

Leptin

Chemical Composition: Leptin Source: Adipose Tissue Stimulus for Secretion: Fatty Foods Target Organ/Effects: Brain: Supresses appetite and increases energy expendature.

Gastrin

Chemical Composition: Peptide Source: Stomach Stimulus for Secretion: Food Target Organ/Effects: Stomach: stimulates glands to release hydrochloric acid (HCI)

Active Vitamin D3

Cholecalciferol, also known as vitamin D3 and colecalciferol, is a type of vitamin D found in food and used as a dietary supplement.

Human Choroinic Gonadotropin (hCG)

During very early pregnancy, a hormone called human chorionic gonadotropin (hCG) is produced by the developing embryo and then by the fetal part of the plecenta.

Estrogens

Female sex hormones

Alpha Cells

Glucagon acts as an antagonist of insulin; that is, it helps to regulate blood glucose levels but in a way opposite to that of insulin. Its release by the alpha cells of the islets is stimulated by low blood levels of glucose. Its action is basically hyperglycemic.

Growth Hormones (GH)

Growth hormone (GH) is a general metabolic hormone. However, its major effects are directed to the growth of skeletal muscles and long bones of the body, and thus it plays an important role in determining final body size.

In the body

H2O (water) always follows sodium. The water stays in the blood because the sodium doesn't leave the vessels. Aldosterone regulates the salt levels in the blood, which maintains blood volume.

Beta Cells

High levels of glucose in the blood stimulate the release of insulin from beta cells of the islets.

Human Placental Lactogen (hPL)

Human Placental Lactogen (hPL) works cooperatively with estrogen and progesterone in preparing the breasts for lactation.

Follice-Stimulating Hormone (FSH)

In females, follicle-stimulating hormone (FSH) stimulates follicle development in the ovaries. As the follicles mature, they produce estrogen, and eggs are readied for ovulation. In males, FSH stimulates sperm development by the testes.

Cholecystokinin (CCK)

In the pancreas it stimulates the release of enzyme-rich juice. In the liver it increases the release of bile. In the stomach it inhibits secretory activity.

Follicles

Internally, the thyroid gland is composed of hollow structures called follicles, which store a sticky colloidal material.

Lutenizing Hormone (LH)

Lutenizing hormone (LH) triggers ovulation of an egg from the female ovary and causes the ruptured follicle to produce progesterone and some estrogen.

Erythropoietin

Made up of glycoprotein, the source of erythropoietin is the kidney. It is stimulated by hypoxia. Within bone marrow, erythropoietin stimulates the production of red blood cells.

Androgens

Regardless of one's gender, both male and female sex hormones are produced by the adrenal cortex throughout life in relatively small amounts. Although the bulk of sex hormones produced by the innermost cortex layer layer are androgens (male sex hormones), some estrogen (female sex hormones) are also formed.

Angiotensin II

Renin, an enzyme produced by the kidneys when blood pressure drops, also causes the release of aldosterone release by triggering a series of reactions that form angiotenin II, a potent simulator of aldosterone release.

Adrenal Cortex

The adrenal cortex produces three major groups of steroid hormones collectively called corticosteroids - mineralocorticoids, glucocorticoids, and sex hormones.

Corticosteroids

The adrenal cortex produces three major groups of steroid hormones collectively called corticosteroids - mineralocorticorteroids, glucocorticoids, and sex hormones.

Endocrine System

The endocrine system coordinates and directs the activity of the body's cells.

Gonadotropic Hormones

The gonadotropic hormones regulate the hormonal activity of the gonad (ovaries and testes).

Hypothalamus

The hypothalamus, which is part of the nervous system, is also recognized as a major endocrine organ because it produces several hormones.

Glucocorticoids

The middle cortical layer of glucocorticoids, which include cortisone and cortisol. Glucocorticoids promote normal cell metabolism and help the body resist long-term stressors, primarily by increasing blood glucose levels.

Cortisol

The middle cortical layer produces glucocorticoids, which include cortisone and cortisol (also known as hydrocortisone).

Cortisone

The middle cortical layer produces glucocorticoids, which include cortisone and cortisol.

Aldosterone

The mineralocorticoids, mainly aldosterone, are produced by the outermost adrenal cell layer.

Hormones; Releasing, Inhibiting

The more slowly acting endocrine system uses chemical messengers called hormones, which are released into the blood to be transported leisurely throughout the body. The anterior pituary is not as all-powerful in its control as it might appear because the release of each of its hormones is controlled by releasing and inhibiting hormones produced by the hypothalamus.

Antidiuretic Hormone (ADH) / Vassopressin

The second hormone released by the posterior pituitary is antidiuretic hormone (ADH). Diuresis is urine production. Thus, an antidiuretic is a chemical that inhibits or prevents urine production.

Calcitonin

The second important hormone product of the thyroid gland, calcitonin, or thyrocalcitonin, decreases blood calcium levels by causing calcium to be deposited in the bones.

Adrenal Glands

The two bean-shaped adrenal glands curve over the top of the kidneys. It is structurally and functionally two endocrine organs in one. Like the pituitary gland, it has glandular (cortex) and neural tissue (medulla) parts. The central medulla region is enclosed by the adrenal cortex, which contains three separate layers of cells.

Insulin Resistance

Those with mild cases of diabetes mellitus (most cases of type II, or adult-onset, diabetes) produce insulin, but for some reason their insulin receptors are unable to respond to it, a situation called insulin resistance.

Sympathomimetic

To mimic the sympathetic nervous system (in assisting fight or flight).

Glucagon

Two important hormones produced by the islet cells are insulin and glucagon. Insulin acts on just about all body cells and increases their ability to transport glucose across their plasma membrane. Once inside the cells, glucose is oxidized for energy or converted to glycogen or fat for storage.

Insulin

Two important hormones produced by the islet cells are insulin and glucagon. Insulin acts on just about all body cells and increases their ability to transport glucose across their plasma membrane. Once inside the cells, glucose is oxidized for energy or converted to glycogen or fat for storage.

Catecholamines

When the medulla is stimulated by sympathetic nervous system neurons, its cells release two similar hormones, epinepherine, also called adrenaline, and norepinepherine (noradrenaline), into the blood stream. Collectively, these hormones are referred to as catecholamines.

Epinephrine

When the medulla is stimulated by sympathetic nervous system neurons, its cells release two similar hormones, epinephrine, also called adrenaline, and norepinephrine (noradrenaline), into the bloodstream.