sucrose pretreatment for frozen sections

[Christine McGregor]

I usually soak formalin-fixed rat brains in 20 % sucrose solution for 24 hours
 prior to frozen-sectioning. Can anyone tell me if there is an upper limit to
 the time the brain can be left soaking...will the formalin fix leach out as
it does in water? Will there be a loss of morphological detail or artefact
from microbes? I am wondering about the effect of a week or two.(refrigerated,
of course).
--
Christine McGregor
Mountain, Ontario
Canada
National Capital Freenet  af826