TISSUE FREEZING METHODS FOR CRYOSTAT （组织冷冻低温恒温器的方法）.pdf

TISSUE FREEZING METHODS FOR CRYOSTAT SECTIONING Basic Tissue Freezing Methods Preparing Tissue for Freezing Then a quick overview of MHPL Cryostat sectioning Techniques: Using The Brush; Using The Anti-Roll Plate; Speaker: Donna J. Emge, HT-ASCP, MHPL Manager Preparing Tissue For Freezing Tissue for freezing should be frozen or fixed as promptly as possible after cessation of circulation to avoid morphological distortions and damage due to: • Tissue drying artifact. • Autolysis - The destruction of tissues or cells by the action of substances, such as enzymes, that are produced within the organism. Also called self-digestion. • Putrefaction - Decomposition by microorganisms. WHY SNAP FREEZE OR FIX AND CRYOPROTECT FOR FREEZING? Slow freezing can cause distortion of tissue due to ice crystal formation that replaces the architecture with a “Swiss Cheese” effect. The object is to freeze so rapidly that water does not have time to form crystals and remains in a vitreous form that does not expand when solidified. Brain Skeletal Muscle Freezing artifact in sections of Brain, Muscle, and Spleen SHORT ARTICLE ON THE SUBJECT OF WATER CRYSTAL FORMATION: “FREEZING BIOLOGICAL SAMPLES” Charles W. Scouten Miles Cunningham /global/Manuals/Tips%20an d%20Techniques%20Freezing%20Artifact.pdf METHODS OF TISSUE FREEZING 1. Fresh tissue freezing – Tissue is in OCT and flash frozen fresh. 2. 4% PFA fixed, sucrose cryoprotected tissue freezing – Tissue is in OCT and may be frozen using dry ice or the flash frozen method. 3. Enzyme study tissue freezing – Often used for fresh muscle tissue. A fresh frozen method w