Hypertoniset

Hypertoniset refers to solutions or environments with higher osmotic pressure or osmolality than a reference solution, typically the intracellular fluid. In biology and medicine, hypertonicity describes conditions where extracellular osmolality exceeds intracellular osmolality, causing water to move out of cells by osmosis.

Mechanism and effects: Water moves across semipermeable membranes in response to solute concentration. When the extracellular space is hypertonic, cells lose water and shrink; in plant cells this can lead to plasmolysis. The extent of the effect depends on the osmotic difference and membrane permeability, as well as the specific solutes involved. Some solutes permeate membranes, which can modulate the outcome.

Common hypertonic substances and uses: Concentrated sodium chloride solutions, mannitol, glycerol, and certain sugars can create hypertonic environments. Clinically, hypertonic saline and other hypertonic solutions are used to draw water from swollen tissues or to manage conditions such as intracranial hypertension. Hypertonic solutions are chosen for their specific osmotic effects, but they require careful monitoring to avoid rapid shifts in electrolytes and osmotic injury.

Related terms and context: Hypertonicity is contrasted with isotonic (equal osmolality) and hypotonic (lower osmolality). The concept is central to osmoregulation in cells and tissues, and it is applied across medicine, physiology, and food science for processes like osmotic dehydration and fluid management. The term derives from Greek roots meaning “excess tension” or tonicity.