[Histonet] Help with cutting mouse brain at 9-10 microns

[Coffey, Anna (NIH/NCI) [C]]

Hi Kimberly,

Most of what I work with is mouse tissue and I've found the brains to be a bit tricky because they both hydrate and dry out quickly. I normally keep the paraffin blocks on an ice for about 2 hours (after they've been fully faced in), checking periodically to make sure the tissue is not overhydrating. When I section, I can normally only take a few sections before the brain starts to dry out again (you can tell when you start to see scratches and dry white areas on the tissue). Most of the blocks are ready to cut again after a few additional minutes back on the ice.

For thicker sections (up to 20um), I take use the wooden stick of a cotton swab and hold it against the base of the paraffin block as I cut the section. The section will curl around the stick and you can roll it out flat on the water bath to smooth it out.

Hope this helps!

Anna Coffey, MS, HTL(ASCP)CM
Histotechnologist
Center for Advanced Preclinical Research
Frederick National Laboratory for Cancer Research
Leidos Biomedical Research, Inc.
Bld 539, 224
Frederick, Maryland 21702
301-846-1730