Osmometric Thirst

Thirst is the craving for liquids, resulting in the basic instinct of humans or animals to drink. It is an essential mechanism involved in fluid balance. It arises from a lack of fluids and/or an increase in the concentration of certain osmolites such as salt. If the water volume of the body falls below a certain threshold, or the osmolite concentration becomes too high, the brain signals thirst.
Continuous dehydration can cause a myriad of problems, but is most often associated with neurological problems such as seizures, and renal problems. Excessive thirst, known as polydipsia, along with excessive urination, known as polyuria, may be an indication ofdiabetes.
Thirst produced by an increase in the osmotic pressure of the interstitial fluid relative to the intracellular fluid thus producing cellular dehydration fluid, Intracellular fluid, fluid contained within cells. Osmometric thirst occurs when the osmotic balance between the amount of water in the cells & the water outside the cells becomes disturbed means when the concentration of salts in the interstitial fluid is greater than that inside the cells, resulting in the movement of intracellular water outside of the cell by osmosis. This is what happens when we eat salty pretzels. The Na is absorbed into the blood plasma, which disrupts the osmotic balance between the blood plasma & the interstitial fluid. This draws water out of the interstitial fluid and into the plasma, now upsetting the balance between the cells and the interstitial fluid. The result is water leaving the cells to restore the balance. The disruption in the interstitial solution is recognized by neurons called osmoreceptors. These osmoreceptors are located in the region of the anterior hypothalamus. These osmoreceptors send a signal that causes us to drink more water, in order to restore the osmotic balance between the cells and surrounding fluid. In the case of pretzel eating, if we do not drink more water, eventually the excess