Andrea,

I agree with John that many of these schedules being quoted are too short
and that the problem may well be that tissue is improperly dehydrated. Our
'short' processing schedule for smaller tissue samples goes through 70%
alcohol (time not critical), 95% alcohol for 1 hour then three changes of
absolute alcohol of 45 to 60 minutes each change. Very small tissue samples
(small animal nerves etc) have shorter times. We still clear in xylene,
three changes of 45 to 60 minutes each, and three wax changes, again, 45 to
60 minutes each using vacuum.

Our third abs alc change is replaced regularly to keep it as free from
water as possible (3 becomes 2; 2 becomes 1, and 1 is discarded).

Ken.

At 03:07 PM 11/18/99 GMT, you wrote:
>
>I too am having problems with my processing of mouse tissues.  I found that
>my schedule of 15-20 min each step was too much and my tissues ended up
>being really crunchy.  So at the NSH conference I talked to people who said
>step down everything to 10 minutes or so and now my tissues are no properly
>embedded and are more difficult to section than ever before plus the
>tissues don't adhere well to silane slides, not to mention the H+E's look
>awful .... HELP!!!
>
>Andrea
>
>
>
Kenneth W Turner
Senior Teaching Fellow
Manager Histology Service Unit
Department of Pathology
Dunedin School of Medicine	    e-mail  ken.turner@stonebow.otago.ac.nz

University of Otago		    Phone:  (03) 479 7135 or (03) 479-7152
New Zealand			    Fax:    (03) 479-7136