PAS diastase

In histology, PAS diastase is stain to ellucidate gastric duodenal metaplasia in duodenal adenomas.^[1] More generally, PAS diastase is a histological stain often used as a negative control for glycogen. Diastase is an enzyme that breaks down glycogen and PAS is a stain that typically gives a magenta colour in the presence of glycogen. When the two are used together a light pink colour replaces the deep magenta. Differences in the intensities of the two stains (PAS and PAS-D) can be attributed to different glycogen concentrations and can be used to semiquantify glycogen in samples.

Additional recommended knowledge

Essential Laboratory Skills Guide

Safe Weighing Range Ensures Accurate Results

Guide to balance cleaning: 8 simple steps

See also

• Periodic acid-Schiff stain
• Diastase

References