L2.7.2: Hormones Produced by Other Organs

• Prostaglandins (PGs), Several groups indicated by letters A-I (PGA-PGI)

  • Derived from fatty acid molecules
  • Plasma membranes of virtually all body cells
  • Various (local irritation, hormones, etc)
  • Have many targets but act locally at the site of release.
• Prostaglandins( PGs), Several groups indicated by letters A-I (PGA-PGI)

  • Examples of effects include the following: -- increase blood pressure by acting as vasoconstrictors; -- cause constriction of respiratory passageways; -- stimulate muscle of the uterus, promoting menstrual pain and labor; -- enhance blood clotting; -- promote inflammation and pain; -- increases output of digestive secretions by stomach; -- cause fever
• Gastrin

  • Peptide
  • Stomach
  • Food
  • Stomach: stimulates glands to release hydrochloric acid (HCl)
• Intestinal gastrin

  • Peptide
  • Duodenum (first segment) of all intestine
  • Food (esp fats)
  • Stomach: stimulates gastric glands and motility
• Secretin

  • Peptide
  • Duodenum
  • Food
  • Pancreas: stimulates release of bicarbonate-rich juice
  • Liver: increases release of bile
  • Stomach: reduces secretions and motility
• Cholecystokinin (CCK)

  • Peptide
  • Duodenum
  • Food
  • Pancreas: stimulates release of enzyme-rich juice
  • Gallbladder: stimulates expulsion of stored bile
  • Duodenal papilla (entry point at the small intestine): causes sphincter to relax, allowing bile and pancreatic juice to enter duodenum
• Erythropoietin

  • Glycoprotein
  • Kidney
  • Hypoxia (low oxygen level)
  • Bone marrow: stimulates production of red blood cells
• Active vitamin D3

  • Steroid
  • Kidney (activates provitamin D made by epidermal cells)
  • PTH
  • Intestine: stimulates active transport of dietary calcium ions across intestinal cell membranes
• Atrial natriuretic peptide (ANP)

  • Peptide
  • Heart
  • Stretching of atria of heart
  • Kidney: inhibits sodium ion reabsorption and renin release
  • Adrenal cortex: inhibits secretion of aldosterone, thereby decreasing blood volume and blood pressure
• Leptin

  • Peptide
  • Adipose tissue
  • Fatty foods
  • Brain: suppresses appetite and increases energy expenditure
• Resistin

  • Peptide
  • Adipose tissue
  • Unknown
  • Fat, muscle, liver: antagonizes insulin’s action on liver cells