Endocrine System Flashcards

Comprehensive vocabulary flashcards covering general endocrine concepts, anatomy, physiology, specific disorders (Pituitary, Thyroid, Parathyroid, Adrenal, Pancreas), and diabetes management.

Ductless

Refers to glands that are "tubeless" and communicate by releasing hormones directly into the BLOOD.

Hormones

Chemical messengers that stimulate endocrine and non-endocrine organs, also known as target organs.

Target organs

Organs that produce a specific response to hormonal stimulation.

Negative feedback loop

A regulatory mechanism that maintains hormone levels to prevent overproduction or underproduction.

Hypothalamus

Synthesizes Oxytocin and Anti-Diuretic Hormone ($ADH$) and produces releasing and inhibiting hormones to regulate the pituitary gland.

Pituitary Gland

The master gland of the system that controls the overall functions of the endocrine system.

Somatotropin

Also known as Growth Hormone ($GH$); it is responsible for muscle and bone growth and is normally increased during SLEEP.

Acromegaly

An endocrine disorder caused by increased $GH$/Somatotropin, characterized by large hands, feet, face, and a protruding jaw.

Hormonal Dwarfism

An endocrine disorder caused by decreased $GH$/Somatotropin, characterized by a toddler-like appearance and underdeveloped body parts.

Thyroid-Stimulating Hormone ($TSH$)

An anterior pituitary hormone that stimulates the release of $T3$ and $T4$ from the thyroid gland.

Prolactin ($PH$)

Promotes breast development during pregnancy and milk production during labor and delivery.

Adrenocorticotropic Hormone ($ACTH$)

Stimulates the adrenal cortex to produce glucocorticoids (Cortisol), mineralocorticoids (Aldosterone), and androgens (Testosterone).

Oxytocin

A posterior pituitary hormone that stimulates the milk "let down" reflex and uterine contractions.

Anti-Diuretic Hormone ($ADH$)

Also known as Vasopressin; it stimulates water reabsorption in renal tubules and vasoconstriction to elevate blood pressure.

SIADH

Syndrome of Inappropriate Antidiuretic Hormone Secretion; caused by increased $ADH$, leading to oliguria ($<30\,mL/hr$) and dilutional hyponatremia.

Diabetes Insipidus ($DI$)

An endocrine disorder caused by decreased $ADH$, characterized by polyuria ($>100\,mL/hr$), low urine specific gravity ($<1.030$), and polydipsia.

Thyrocalcitonin/Calcitonin

A thyroid hormone that removes calcium from the blood and places it into the bones (bone resorption).

Grave’s Disease

Also known as Toxic Diffuse Goiter or Basedow’s Disease; the most common autoimmune disorder causing hyperthyroidism.

Exophthalmos

A sign of hyperthyroidism characterized by protruding eyes, managed with eye drops or taping eyes during sleep.

Hashimoto’s Thyroiditis

The most common autoimmune disorder leading to hypothyroidism.

Trousseau’s Sign

A carpopedal spasm induced by inflating a blood pressure cuff; a sign of hypocalcemia (tetany).

Chvostek’s Sign

Facial muscle twitching when the facial nerve is tapped; an indicator of hypocalcemia (tetany).

Parathyroid Hormone ($PTH$)

A hormone that promotes bone resorption to move calcium from the bone into the blood.

Cushing’s Disease

A condition caused by hypersecretion of corticosteroids, characterized by moon face, truncal obesity, buffalo hump, and reddish-purple striae.

Addison’s Disease

A condition caused by the hyposecretion of adrenal cortex hormones, characterized by bronze skin pigmentation, dehydration, and hypotension.

Hirsutism

Excessive hair growth in a male-like pattern, often seen in females with Cushing's Disease due to increased androgens.

Pheochromocytoma

A tumor in the adrenal medulla that produces excessive catecholamines, causing severe hypertension, tachycardia, and headaches.

Islets of Langerhans

The endocrine part of the pancreas consisting of Alpha cells (Glucagon) and Beta cells (Insulin).

Type 1 Diabetes

Insulin-Dependent Diabetes Mellitus ($IDDM$) caused by beta cell destruction, usually occurring in patients under $30$ years old.

Diabetic Ketoacidosis ($DKA$)

A sudden complication of Type 1 DM involving metabolic acidosis, Kussmaul’s respiration, and personal fruity odor breath.

HHNS

Hyperosmolar Hyperglycemic Nonketotic Syndrome; a gradual complication of Type 2 DM featuring extreme hyperglycemia ($>800\,mg/dl$) without ketone production.

Somogyi Phenomenon

Rebound Hyperglycemia upon awakening caused by an excessive insulin dose at night.

Dawn Phenomenon

Hyperglycemia upon awakening caused by a lack of insulin at night combined with the dawn release of growth hormone and cortisol.

Metformin

A Biguanide that reduces glucose production; it must be withheld around contrast dye procedures to prevent lactic acidosis and $AKI$.

Lipodystrophy/Lipohypertrophy

Skin changes caused by repeated insulin injections at the same site, which can lead to unpredictable insulin absorption.

Diabetic Neuropathy

Deterioration of the nervous system due to poor circulation, which can affect sensory, focal, or autonomic functions.