Biomaterial Database

Comparison of ultrastructure of germinating pea leaves prepared by high-pressure freezing-freeze substitution and conventional chemical fixation. 1995

Y Kaneko, and P Walther

Department of Regulation Biology, Faculty of Science, Saitama University, Urawa, Japan.

High-pressure freezing-freeze substitution (HPF-FS) methods were applied to germinating pea leaves. Good ultrastructural preservation without visible freezing damage was obtained up to 200 microns in thickness. Compared to conventional chemical fixation (CF), cellular membranes were smoother without undulation, and organelles appeared more turgid. The matrices of cytoplasm and organelles were denser and more homogeneous. The features imply that HPF-FS samples retain more substances and ultrastructure closer to the living state. There were differences in membrane stainability among organelles in HPF-FS specimens, which were not seen after CF. Bundles of microfilaments were observed frequently after HPF-FS.

UI	MeSH Term	Description	Entries
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D005615	Freezing	Liquids transforming into solids by the removal of heat.	Melting
D005976	Glutaral	One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.	Glutaraldehyde,Cidex,Diswart,Gludesin,Glutardialdehyde,Glutarol,Korsolex,Novaruca,Sekumatic,Sonacide,Sporicidin
D014021	Tissue Preservation	The process by which a tissue or aggregate of cells is kept alive outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).	Preservation, Tissue,Preservations, Tissue,Tissue Preservations
D017110	Freeze Substitution	A modification of the freeze-drying method in which the ice within the frozen tissue is replaced by alcohol or other solvent at a very low temperature.	Substitution, Freeze
D018515	Plant Leaves	Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)	Plant Leaf,Leaf, Plant,Leave, Plant,Leaves, Plant,Plant Leave
D018532	Pisum sativum	A variable annual leguminous vine that is cultivated for its rounded smooth or wrinkled edible protein-rich seeds, the seed of the pea, and the immature pods with their included seeds. (From Webster's New Collegiate Dictionary, 1973)	Peas,Pisum,Pea