Which two glycogen fixatives preserve the most glycogen?

• A. Bouins & Rossman’s
• B. Bouins & Zenkers
• C. Bouins only
• D. Zenkers & Helly

Answer: (A)

Glycogen is water-soluble, so it can be lost from tissue during fixation and processing if the fixative is aqueous or tends to extract soluble carbohydrates. Fixatives that are non-aqueous or that precipitate or immobilize carbohydrates help keep glycogen in place, yielding stronger glycogen preservation and better PAS positivity after staining.

Bouin’s solution provides strong coagulative fixation with components that help immobilize carbohydrates, while Rossmann’s fixative is known to preserve carbohydrates well because of its solvent balance that reduces glycogen leaching. Together, they minimize glycogen loss during processing, making this pair the most effective among common fixatives for retaining glycogen in tissue.

In contrast, fixatives that are more aqueous or that fix by diffusion in water tend to wash glycogen out, leading to poorer preservation.