thirst

• Hypovolemic Thirst


  Thirst based on low volume
• Vasopressin

  Raises blood pressure by constricting blood vessels to compensate for decreased blood volume
• Vasopressin


  Also called Antidiuretic Hormone (ADH), facilitates water reabsorption in the kidneys, leading to concentrated urine. Helps conserve body water, particularly during sleep when drinking is not possible
• Angiotensin II


  Indicates low blood volume, significantly amplifies preference for salt, leading individuals to seek out salty foods
• Osmotic Pressure


  Tendency of water to flow across a semipermeable membrane from low solute concentration to higher concentration
• OVLT

  Communicates with other brain regions, such as the hypothalamus, to regulate thirst and fluid balance
• Subfornical Organ function


  Relays information to several parts of the hypothalamus, including the Supraoptic nucleus and the paraventricular nucleus (PVN), which control the rate of vasopressin release. Also relays information to the Lateral Preoptic Area and surrounding parts of the hypothalamus, which control drinking
• Sodium-specific Hunger


  Craving for salty tastes, innate preference that develops automatically when body's sodium reserves are low. Plays a crucial role in maintaining electrolyte balance and hydration levels in the body. Driven by hormones such as aldosterone and angiotensin II
• Osmotic Thirst


  Triggered by certain neurons detecting their own loss of water to restore the normal state
• Aldosterone


  Produced by adrenal glands, signals low sodium levels, significantly amplifies preference for salt, leading individuals to seek out salty foods
• Areas important for detecting osmotic pressure and salt content


  • OVLT (organum vasculosum laminae terminalis)
  • Subfornical Organ (SFO)
• Angiotensin II

  Constricts blood vessels to compensate for drop in blood pressure and triggers thirst, in conjunction with receptors detecting blood pressure in the large veins