If the tissue isn't ixed well you will have tissue destruction from
digestion. If overfixes, less signal. It seems some fixation trials are in
order for this study!

Tim Morken, BA, EMT(MSA), HTL(ASCP)
Infectious Disease Pathology Activity
Centers for Disease Control and Prevention
Ms-G32
1600 Clifton Road
Atlanta, GA 30333
USA

PH: 404-639-3964
FAX: 404-639-3043

email: tim9@cdc.gov



-----Original Message-----
From: Sarah LaBonte [mailto:slabonte@cvm.tamu.edu]
Sent: Thursday, March 22, 2001 4:11 PM
To: HistoNet@Pathology.swmed.edu
Subject: Fixation times for insituhybridization


We are having an ongoing debate about the fixation times for paraffin
sections that will be used for insituhybridization.  We have one researcher
that is fixing whole cross sections of horse testis for only 24 hours in 4%
paraformaldehyde.  12 of these hours are in the refrigerator. The tissues
can be as big as a cassette will hold.  I was told that fixation for ISH is
usually minimal and was wondering if it requires less than optimal fixation.
They are worried about over fixation, but the centers of the testis are
obviously not fixed well.  Comments?  thanks, Sarah

Sarah LaBonte, HT (ASCP)
Research Associate, Histology Lab
Texas A&M University
College of Veterinary Medicine
Dept. of Vet Anatomy & Public Health
College Station, TX  77843-4458
phone: (979) 845-3177
fax:  (979) 458-3499