A CHEMICAL AND HISTOCHEMICAL INVESTIGATION OF GLYCOGEN IN RAT LIVER AND PALATE FOLLOWING TREATMENT WITH VARIOUS FIXATIVES AND ETHYLENEDIAMINE TETRAACETIC ACID

Abstract

The loss of glycogen after fixation in acetic acid-alcohol-formalin as compared to immediate determination was found by chemical analysis to be from 5.2% to 13.8%. No appreciable difference could be seen histochemically. Chemical analysis of the glycogen content of liver fixed in acetic acid-alcohol-formalin and then treated in ethylenediamine tetracetic acid showed a total drop of 20.7 to 33.7%. Glycogen could still be adequately shown histochemically. Sections taken from liver fixed in 1% periodic acid in 10% formalin show greater amounts of glycogen, than those taken from acetic-acid-alcohol-formalin fixed tissue. After fixation in 1% periodic acid in 10% formalin and following treatment with ethylenediamine tetraacetic acid, very little glycogen could be demonstrated histochemically. In the palate, no glycogen could be demonstrated after fixation in acetic acid-alcohol-formalin, whereas quite heavy amounts could be seen in the prickle cell layers of the epithelium following fixation in 1% periodic acid in 10% formalin. Neither acetic acid-alcohol-formalin nor 1% periodic acid in 10% formalin are satisfactory fixatives if the tissue is to be further decalcified in ethylenediamine tetraacetic acid, if there are only small amounts of glycogen present. No adequate method of retaining glycogen in small amounts in tissue requiring decalcification can be suggested.