Hormones

DS1101 Endocrine System Hormones Flashcards

ADH (Vasopressin)

Source: posterior pituitary (Made in hypothalamus)

Trigger: High plasma osmolarity

Key function: water reabsorption in kidneys; vasoconstriction at high concentration

Oxytocin

Source: Posterior pituitary (made in hypothalamus)

Trigger: Cervical stretch (Positive FB)

Key function: Uterine contractions ; milk let-down, bonding

FSH (follicle stimulating hormone)

Source: Anterior pituitary

Trigger: Gonadotropin-releasing hormone (GnRH) from hypothalamus

Key function: gamete production and maturation, follicular growth

LH

Source: Anterior pituitary

Trigger: Gonadotropin-releasing hormone (GnRH) from hypothalamus

Key function: Ovulation, sex hormone production.

Prolactin

Source: Anterior pituitary

Trigger: Suckling; TRH; oxytocin

Key function: lactation; breast development

GH

Source: Anterior pituitary

Trigger: GHRH; inhibited by GHIH

Key function: growth (via IGFs) , metabolism regulation

ACTH

Source: Anterior Pituitary
Trigger: CRH; stress; low glucose

Key Function: stimulates cortisol production from adrenal glands

TSH

Source: Anterior Pituitary

Trigger: TRH from hypothalamus

Key Function: stimulates thyroid hormone production → T3 & T4

Aldosterone

Source: Adrenal cortex → zona glomerulosa

Trigger: Low Na+, BP, or blood volume

Key Function: Sodium retention, Potassium excretion → raises blood volume/pressure

Cortisol

Source: Adrenal cortex → zona fasciculata

Trigger: ACTH ; chronic stress

Key Function: glucose metablosim, anti-inflammatory, catabolism

Adrenaline

Source: Adrenal medulla

Trigger: Acute Stress (sympathetic)

Key Function: Fight or flight, increased HR, glucose, BP

T3/T4

Source: Thyroid follicle cells

Trigger: TSH from anterior pituitary

Key Function: Regulate BMR; essential for development; sensitize to catecholamines

Calcitonin

Source: Thyroid C cells (parafollicular)

Trigger: High blood calcium

Key Function: Lowers blood calcium — inhibits osteoclasts, promotes osteoblasts

PTH

Source: Parathyroid chief cells

Trigger: Low blood calcium

Key Function: Raises blood calcium — via kidneys, bone resorption, calcitriol (biologically active form of Vitamin D)

Insulin

Source: beta cells in pancreas

Trigger: high blood glucose; GI hormones

Key function: lowers glucose; glycolysis; glycogensis, lypogenesis, protein synthesis. Inhibits glycogenolysis, gluconeogenesis, lipolysis

Glucagon

Source: Alpha cells (pancreas)

Trigger: Low blood glucose

Keyfunction: Raises glucose: stimulates glycogenolysis gluconeogenesis, lipolysis

Somatostatin

Source: Delta Cells

Trigger: high glucose or amino acids

Key function: inhibits both insulin and glucagon

Pancreatic Polypeptide

Source: PP Cells

Trigger: Eating / vagal tone

Keyfunction: Regulates appetite and pancreatc secreations

Melatonin

Source: Pineal gland

Trigger: Darkness / declining light levels

Key function: Causes drowsiness ; regulates sleep - wake cycle

Calcitriol (Active Vit D3)

Source: Kidneys

Trigger: PTH secretion

Keyfunction: Raises blood calcium vio bone resorption, intestinal and renal absorption

EPO (Erythropoietin)

Source: Kidneys

Trigger: Low oxygen/Hypoxia

Keyfunction: Stimulates red blood cell production in bone marrow

Leptin

Source: Adipose tissue

Trigger: Fat stores; eating

Keyfunction: Signals satiety; reduced appetite

Adiponectin

Source: Adipose tissue

Trigger: Inversely with fat (Rises with weight loss)

Key function: Reduces insulin resistance ; protects vessels from inflammation and atherosclerosis