Vibratome

Vibratome is a specialized instrument used in histology and anatomy to cut thin slices of fresh, unfixed tissue. Unlike traditional microtomes, which require embedding and freezing or fixing the tissue before sectioning, a vibratome uses a vibrating blade to cut through the tissue, minimizing cell distortion and preserving the structural integrity of the sample. This method is particularly valuable for preparing specimens for immunohistochemistry, in situ hybridization, and live tissue imaging.

Overview

The vibratome operates by securing the tissue in a tray or chuck using agarose or a similar medium. The tissue is then partially submerged in a buffer solution to keep it hydrated during the cutting process. A blade, typically made of steel or sapphire, is attached to a vibrating arm. The vibration amplitude and speed can be adjusted to optimize cutting conditions for different tissue types and thicknesses. The vibratome slices the tissue by moving the vibrating blade across it, producing sections that can range from 10 to 1000 micrometers in thickness.

Advantages

The primary advantage of using a vibratome is the ability to prepare sections of live tissue without the need for fixation or embedding. This preserves the native state of proteins, nucleic acids, and other cellular components, making vibratome sections ideal for techniques that require intact cellular architecture and unaltered molecular profiles. Additionally, the absence of freezing or embedding artifacts enhances the quality of the tissue sections, providing clearer images under the microscope.

Applications

Vibratome sections are widely used in neuroscience, developmental biology, and plant biology for:

• Immunohistochemistry: to study the distribution and localization of proteins within tissues.
• In situ hybridization: to examine the spatial expression patterns of genes.
• Electrophysiological studies: to investigate the properties of live cells within intact tissue slices.
• Confocal microscopy: to obtain high-resolution images of fluorescently labeled components in thick tissue sections.

Limitations

While vibratomes offer significant advantages, there are limitations to consider. The technique requires skill and experience to optimize cutting conditions and achieve consistent section thickness. Additionally, the integrity of very soft or brittle tissues may be compromised during sectioning, necessitating the use of embedding compounds that can be removed post-sectioning without affecting tissue integrity.

Maintenance and Care

Proper maintenance of the vibratome is crucial for its performance and longevity. This includes regular cleaning of the blade and cutting area, ensuring the blade is sharp and free of nicks, and calibrating the vibration frequency and amplitude settings according to the manufacturer's instructions.

See Also

• Microtome
• Histology
• Immunohistochemistry
• In situ hybridization