SURVIVAL OF ENZYMES IN SECTION FROZEN-SUBSTITUTED TISSUES

Abstract

Enzyme activities in tissues which have been section frozen-substituted or formol-calcium-fixed have been assayed chemically. The enzymes determined include alkaline and acid phosphatase, adenosine triphosphatase, 5'-nucleotidase, glucose-6-phosphatase, succinic dehydrogenase, as well as di- and triphosphopyridine nucleotide diaphorases. It was found that 22% of glucose-6-phosphatase and more than 70% of the other enzymes assayed could be recovered from the section frozen-substituted tissues. These percentages of recovery are much higher than those obtained in tissues which are fixed in formol-calcium or acetone, or frozen-dried.