Table 3.

Selected cryoprotective agents that have been used for structural brain preservation and their reported effects.

Cryoprotective agent	Biospecimen preserved and CPA delivery method	Reported histologic outcome
15% glycerol	Perfusion-based cryoprotection of cat brains	Close to normal cell arrangements with Nissl staining (64)
10% DMSO	Immersion cryoprotection of rat embryonic brain tissue	Histologically normal-appearing tissue with cresyl violet staining (65)
M22 vitrification solution	Perfusion-based cryoprotection of rabbit brains	Shrunken but reportedly preserved cells, images difficult to interpret (52)
VM3 vitrification solution	Immersion cryoprotection of thin rat hippocampal slices	High-quality ultrastructure essentially equivalent to controls, with adequate uptake of CPA in the vitrification procedure (66)
13% glycerol, 13% DMSO	Perfusion-based cryoprotection of rat brains	Preserved synaptic immunostaining, fainter NeuN staining, shrinkage of neurons (63)

DMSO, dimethyl sulfoxide; M22 and VM3, vitrification solutions composed of multiple cryoprotectants; NeuN, neuronal nuclei, a neuronal marker protein; CPA, cryoprotective agent.