Staining, Histochemistry and Histotechnology
(Frequently Asked Questions)
Dr. John A. Kiernan
Department of Anatomy
and Cell Biology
The University of Western Ontario
(amylase) control for glycogen
Which is better as a control for glycogen staining: alpha-amylase or human saliva?
The bought enzyme (10 mg/ml, in water) takes about 10 minutes to remove the stainable glycogen from a section of liver. The enzyme is not very expensive.
Saliva is free, and it takes about 30 minutes, but some people don't enjoy spitting, or even dribbling, onto their slides. A theoretical disadvantage of spit is that it contains plenty of digestive enzymes additional to amylase (= diastase), notably ribonuclease and various proteases. However, these are unlikely to remove substances with the same staining properties as glycogen.
John A. Kiernan