crenation The shrinkage of cells that occurs when the surrounding solution is hypertonic to the cellular cytoplasm. Water leaves the cells by osmosis, which causes the plasma membrane to wrinkle and the cellular contents to condense.

What causes crenation?

When a red blood cell is placed in a hypertonic solution, such as a highly saline environment, there is a lower concentration of solute particles inside the cell than outside in the extracellular space. ... As water leaves the cell, it shrinks and develops the notched appearance characteristic of crenation.

What causes crenation of RBC?

Crenated erythrocytes are most commonly caused by excess EDTA (underfilled collection tube), but may also be caused by (a) slow drying, (b) drying in a humid environment, or (c) an alkaline pH from glass slides. When crenation is an artifact, most cells on the slide will exhibit this characteristic.