Which of the following are listed as other glycogen fixatives?

• A. 80% alcohol, alcoholic formalin (37% formalin, 95% alcohol), acetic alcohol formalin, aqueous solution (formalin)
• B. Bouins
• C. Mercuric chloride fixatives
• D. Gomori aldehyde fixative

Answer: (A)

Glycogen can be easily washed out of tissue by water-containing fixatives, so preserving it requires alcohol-rich or non-aqueous fixatives that precipitate or protect the carbohydrate rather than dissolve it. The listed alcohol-based options are known to preserve glycogen because they dehydrate and fix the tissue while preventing glycogen loss: 80% alcohol fixes by dehydration and precipitation; alcoholic formalin combines fixation with an alcohol medium to minimize leaching; acetic alcohol formalin adds alcohol with acetic acid in the fixative, which also supports glycogen preservation; and even formalin in aqueous solution is cited in some protocols as part of glycogen-fixation approaches. In contrast, fixatives like Bouins, mercuric chloride solutions, or Gomori aldehyde fixative are not specifically recognized as the glycogen-preserving choices in this context, so they aren’t listed as the “other glycogen fixatives.”