Endocrine System and Hormonal Regulation

Comprehensive vocabulary flashcards detailing the glands, hormones, and physiological pathways of the human endocrine system based on the lecture material.

Hypothalamus

A brain region that produces and secretes GnRH, TRH, GHRH, GHIH, PRH, PIH, and CRH; produces ADH and oxytocin (stored in the posterior pituitary); and sends nerve impulses to the adrenal medulla.

Anterior Pituitary

An endocrine gland that produces and secretes LH, FSH, TSH, GH (growth hormone), prolactin, and ACTH.

Posterior Pituitary

A gland section that stores and secretes ADH (for water retention in nephron collecting ducts) and oxytocin (for uterine contractions and mammary gland stimulation).

Adrenal Cortex

The outer region of the adrenal gland that produces and secretes glucocorticoids (cortisol) and mineralocorticoids (aldosterone) when stimulated by ACTH.

Adrenal Medulla

The inner part of the adrenal gland that produces and secretes adrenaline and noradrenaline in response to direct nerve impulses from the hypothalamus.

Thyroid Gland

An endocrine gland that produces and secretes thyroid hormone ($T_3/T_4$) and calcitonin, a peptide hormone that reduces blood calcium levels.

Parathyroid Gland

An endocrine gland that produces and secretes parathyroid hormone, a peptide hormone that acts on bones to increase blood calcium levels.

GnRH (Gonadotropin-Releasing Hormone)

A hormone produced and secreted by the hypothalamus that acts on the anterior pituitary to release LH and FSH.

TRH (Thyrotropin-Releasing Hormone)

A hormone produced by the hypothalamus that targets the anterior pituitary to secrete TSH, which in turn stimulates the thyroid gland to release $T_3/T_4$.

CRH (Corticotropin-Releasing Hormone)

A hypothalamic hormone released in response to stress that signals the anterior pituitary to produce and release ACTH.

GHRH (Growth Hormone Releasing Hormone)

A hormone produced by the hypothalamus that stimulates the anterior pituitary to release growth hormone (GH).

GHIH (Growth Hormone Inhibiting Hormone)

A hormone produced by the hypothalamus that inhibits the anterior pituitary from releasing growth hormone (GH).

PRH (Prolactin Releasing Hormone)

A hormone produced by the hypothalamus that stimulates the anterior pituitary to release prolactin.

PIH (Prolactin Inhibiting Hormone)

A hormone produced by the hypothalamus that inhibits the secretion of prolactin from the anterior pituitary.

ACTH (Adrenocorticotropic Hormone)

A hormone produced and secreted by the anterior pituitary that prompts the adrenal cortex to release glucocorticoids (cortisol) and mineralocorticoids (aldosterone).

ADH (Vasopressin)

A hormone produced in the hypothalamus, stored and secreted by the posterior pituitary, that acts on the nephron collecting duct to cause water retention.

Oxytocin

A hormone produced in the hypothalamus and secreted by the posterior pituitary that causes contraction of the uterus to induce labor and stimulates mammary glands.

Follicle-Stimulating Hormone (FSH)

A peptide hormone from the anterior pituitary that stimulates follicle maturation and estrogen production in females, and acts on Sertoli cells in males.

Luteinizing Hormone (LH)

A peptide hormone from the anterior pituitary that triggers ovulation in females and targets Leydig cells to produce testosterone in males.

Estrogen (Estradiol)

A steroid hormone produced by maturing follicles and the corpus luteum; low levels inhibit LH and stimulate FSH, whereas high levels stimulate LH and inhibit FSH.

Progesterone

A steroid hormone produced by the corpus luteum that stimulates endometrial growth.

Inhibin

A hormone secreted by the corpus luteum in females and Sertoli cells in males that functions to inhibit FSH secretion.

Leydig Cells

Cells located in the testes that produce and secrete testosterone when stimulated by LH.

Sertoli Cells

Testicular cells stimulated by FSH and testosterone to produce androgen binding protein (ABP) and promote sperm growth.

Androgen Binding Protein (ABP)

A protein produced by Sertoli cells under the influence of FSH and testosterone that promotes sperm growth.

Testosterone

A steroid hormone secreted by Leydig cells that responsible for male sex characteristics, stimulates Sertoli cells, and inhibits LH secretion.

Adrenaline (Epinephrine)

An amine hormone composed of one amino acid released by the adrenal medulla that causes blood vessels of vital organs to dilate, non-vital vessels to contract, heart muscles to contract faster, and glucagon to turn to glucose in the liver.

Cortisol

A glucocorticoid steroid hormone released by the adrenal cortex that breaks down proteins and lipids into glucose and exerts anti-inflammatory effects.

Aldosterone

A mineralocorticoid steroid hormone produced by the adrenal cortex that acts on the distal convoluted tubule of the kidney to cause $Na^+$ reabsorption and $K^+$ secretion.

Insulin

A peptide hormone produced and secreted by pancreatic beta cells when blood glucose rises, causing cells to absorb glucose from the blood.

Glucagon

A peptide hormone produced and secreted by pancreatic alpha cells when blood glucose drops, causing liver glycogen to convert into glucose.

Beta Cells

Endocrine cells in the pancreas that produce and secrete the peptide hormone insulin.

Alpha Cells

Endocrine cells in the pancreas that produce and secrete the peptide hormone glucagon.