Kokonaisosmolariteetin

Kokonaisosmolariteetti, often abbreviated as T.O. or TOsm, refers to the total osmolar concentration of a solution. In biological contexts, it most commonly pertains to the osmolarity of body fluids, such as blood plasma, urine, or intracellular fluid. Osmolarity is a measure of the solute concentration in a solution, specifically the number of osmoles (the number of moles of solute particles that contribute to osmotic pressure) per liter of solvent.

In physiological terms, kokonaisosmolariteetti is a crucial parameter for maintaining cellular homeostasis. Cells regulate their volume by adjusting their internal osmolarity to match that of their surrounding environment. Deviations in body fluid osmolarity can trigger responses from the body, such as the release of hormones like antidiuretic hormone (ADH), which influences water reabsorption in the kidneys to help correct osmolar imbalances.

Normal plasma osmolarity in humans is typically around 280-295 milliosmoles per kilogram (mOsm/kg). Urine osmolarity, however, can vary significantly depending on hydration status and the body's need to conserve or excrete water, ranging from about 50 mOsm/kg in very dilute urine to over 1200 mOsm/kg in concentrated urine. Measuring kokonaisosmolariteetti can be done using an osmometer and is a valuable diagnostic tool for assessing kidney function, hydration levels, and electrolyte disturbances. For example, significantly elevated or decreased osmolarity can indicate conditions like dehydration, overhydration, diabetes insipidus, or certain types of kidney failure.