Fixation by Means of Glutaraldehyde-Hydrogen Peroxide Reaction Products

Improvements in fixation were previously observed dehyde-H202 mixtures (2). The effectiveness of the in specimens treated either by a weak H 2O2 solu- H202 treatment was presumed to depend on the tion followed by glutaraldehyde (1) or by glutaral- activity of reaction products of H 20 2 and glutaral-FIGURE 1 Control fixation. Cross-section through a root of the sixth abdominal ganglion of crayfish Shrinkage is apparent, primarily in central areas of the root (inset, phase-contrast microscopy). The profile of the axons is distorted. Microtubules are poorly preserved and several axon-surface membranes are broken (arrowheads). Large cisterns (C) result from the rupture of small contiguous axons into common cavities. X 8700. Inset, X 270. FIGURE 2 Glutaraldehyde-H202 fixation. Cross-section through a root from the sixth abdominal ganglion of crayfish. The general architecture of the root is well preserved also in central areas where even the smallest axons can be resolved (inset, phase-contrast microscopy). Most of the axons have a circular profile. The microtubules are homogeneously distributed and broken membranes are rarely seen. X 8700. Inset, X 270.