Endocrine System Visual Hypothalamus-to-Target Flow

Vocabulary flashcards covering hormone classifications, hypothalamic-pituitary pathways, target organ actions, feedback mechanisms, and associated conditions from the endocrine system lecture notes.

Amino Acid Derivatives

A class of hormones built from the amino acid tyrosine, including triiodothyronine and thyroxine (built by thyroid follicular cells with iodine) and catecholamines like epinephrine and norepinephrine (produced by adrenal-medulla secretory cells).

Peptide Hormones

A class of hormones built from chains of amino acids, including glycoproteins with carbohydrate side chains (TSH, FSH, LH), hypothalamic regulatory hormones, prolactin, growth hormone, MSH, ADH, and oxytocin.

Lipid Derivatives

Steroid hormones built from cholesterol that travel attached to special carrier proteins, including glucocorticoids (cortisol, corticosterone, cortisone) and small quantities of androgens from the adrenal cortex, estrogen and progesterone from the ovaries, and testosterone from testicular interstitial endocrine cells.

Thyrotropin-Releasing Hormone

A peptide hormone built from amino acids, synthesized by hypothalamic neurosecretory neurons, that travels through the hypophyseal portal system to stimulate the release of thyroid-stimulating hormone from anterior-pituitary basophils.

Thyroid-Stimulating Hormone

A peptide glycoprotein built from amino acids with carbohydrate side chains, produced by anterior-pituitary basophils, that circulates freely in blood to stimulate the thyroid gland.

Corticotropin-Releasing Hormone

A peptide hormone built from amino acids made by hypothalamic neurosecretory neurons that moves through the hypophyseal portal system to stimulate adrenocorticotropic hormone synthesis.

Adrenocorticotropic Hormone

A peptide hormone produced by anterior-pituitary basophils that circulates freely in blood and stimulates the adrenal-cortex zona fasciculata to produce glucocorticoid steroid hormones.

Gonadotropin-Releasing Hormone

A peptide hormone made by hypothalamic neurosecretory neurons that uses the hypophyseal portal system to trigger the anterior pituitary gland to produce follicle-stimulating hormone and luteinizing hormone.

Follicle-Stimulating Hormone

A peptide glycoprotein produced by anterior-pituitary basophils that circulates freely to stimulate ovarian-follicle development in females and promote sperm development in males.

Luteinizing Hormone

A peptide glycoprotein produced by anterior-pituitary basophils that induces ovulation and progesterone secretion in females, and stimulates androgen production (including testosterone) in males.

Prolactin

A peptide protein built from one hundred ninety-eight amino acids, produced by anterior-pituitary acidophils, that acts directly on extracellular receptors in mammary glands to stimulate development and milk production.

Growth Hormone

A protein built from one hundred ninety-one amino acids, produced by anterior-pituitary acidophils, that promotes tissue growth, amino-acid uptake, and energy mobilization, and stimulates liver cells to release somatomedins.

Melanocyte-Stimulating Hormone

A peptide hormone produced by the anterior pituitary gland that binds extracellular receptors on melanocytes using cyclic adenosine monophosphate as a second messenger to stimulate melanin production.

Antidiuretic Hormone

A short-chain peptide built from nine amino acids, synthesized by neurons in the hypothalamic supra-optic nucleus, transported down axons, stored and released by the posterior pituitary gland to cause water retention in the kidneys.

Oxytocin

A short-chain peptide built from nine amino acids, synthesized by neurons in the hypothalamic paraventricular nucleus, released by the posterior pituitary gland, that stimulates uterine contractions during labor, milk ejection, and contractions in the prostate gland and ductus deferens.

Epinephrine and Norepinephrine

Catecholamine amino acid derivatives derived from tyrosine, produced by modified sympathetic secretory cells in the adrenal medulla following direct sympathetic neural stimulation to mediate fight-or-flight responses.

Cushing Disease

A pathological condition caused by an excess secretion of glucocorticoid steroid hormones from the adrenal-cortex zona fasciculata.

Addison Disease

A pathological condition caused by insufficient secretion of glucocorticoid steroid hormones from the adrenal-cortex zona fasciculata.

Testicular Nurse Cells

Cells in the testes that support sperm production and release the hormone inhibin, which acts in a negative-feedback loop to inhibit hypothalamic and anterior-pituitary secretion.

Somatomedins

Hormones released by liver cells when stimulated by growth hormone that promote growth and energy effects in tissues such as long bones, skeletal muscle, epithelia, and connective tissue.

Supra-optic Nucleus

A hypothalamic structure containing neurons that synthesize antidiuretic hormone (ADH) in response to osmoreceptor stimulation.

Paraventricular Nucleus

A hypothalamic structure containing neurons that synthesize oxytocin in response to sensory stimulation.

Hypophyseal Portal System

The vascular transport route through which hypothalamic releasing and inhibiting hormones move to reach the anterior pituitary gland.

Pathway Color Coding Legend

The visual scheme where blue indicates hypothalamus signal/route, teal indicates pituitary output/blood transport, green indicates endocrine organ/downstream hormone, gray indicates final target/function, and gold indicates negative feedback or control.