[Histonet] Re: Animal tissue

[Johnson, Teri]

Consider changing your clearants from xylene to the xylene substitutes,
it'll help make your tissues less brittle. We have one station of xylene
(due to a relatively high summer humidity - and its increased tolerance
for water carryover) and then two stations of aliphatic hydrocarbon (the
stuff that does not smell like oranges). Although the Limonenes would
work very well, many people have a hypersensitivity to the odor.

I ditto what everybody else said about less time in the dehydrating
stations as well. Most of our mouse samples do well with 20-30 minutes
per station. We do recommend you dissect larger organs, like liver, and
bisect things like kidney, testis, heart and brain for better fluid
penetration.

We fix our samples off the processor for whatever the recommended time
is, and store them in 70% alcohol until ready to process. Our first
station on the processor is 70% alcohol.

We have also added glycerol to 100% alcohol (5% v/v) for processing some
samples like pancreas (20 minutes/station) and femur (more extended
processing schedule).

For sectioning samples that seem to be a bit too dry, brief soaking with
ice water or dilute downy usually works well.

You might also benefit by using a different paraffin, one especially
formulated for infiltration. As a last bit of advice, keep your
embedding paraffin stirred well before using to keep the polymers in
solution for easier sectioning.

Good luck!

Teri Johnson, HT(ASCP)QIHC
Managing Director Histology Facility
Stowers Institute for Medical Research
1000 E. 50th St.
Kansas City, MO 64110