Hi What Dolores has said is correct. Zinc formalin is a good fixative for skin. Rodent skin has additional difficulties because of the fur and the keratin involved with the follicles/hair. The tissue sections should not be more than 3 -4 mm in thickness. Also having that large a piece of tissue in a cassette (length) can also contribute to some problems - not just with fixation but with how it is placed in the cassette for processing, then embedding and I'm sure with cutting. My experments with rodent (rat & mouse) had all fixation done off of the processor, on a shaker (belly dancer platform) for twenty four hours. Tissue was then washed in running tap water for thirty minutes and then placed in 70% ethanol for processing. The ratio of solution/tissue was 20X. No fixation was done on the processor as it would interfere with our other protocols. The actual processing time was 10.5 hours. I started with 70%, 80%, 2 - 95%, 2 - abs. etoh, 50/50 - abs/xylene, 2 - xylene and 4- changes paraffin. I was using an older Tissue tec processor with heat for reagents at 37 degrees C w/ vacuum and pressure. Watch your temperatures on the processor because if reagents become too hot it will dry out and damage the tissue. Paraffin was set at 65 degrees C using paraplast 2 also using vacuum and pressure.
Not knowing what your protocol may be sort of leaves me giving you only generalities, if there is anything that I can assist you with further let me know. Good luck. Vikki On Thu, Jan 27, 2011 at 12:35 PM, Fischer, Dolores < dolores_fisc...@baxter.com> wrote: > The section of skin is too large. It should be no thicker than > approximately 3mm. If you need to see the entire piece of skin, you should > be able to submit multiple thin sections. A standard 12hr processing > schedule works. I am not familiar with zinc formalin, but the standard > fixation time for formalin is, minimally 24hrs, therefore I would guess your > fixation time is also too short. > > Dolores > > -----Original Message----- > From: histonet-boun...@lists.utsouthwestern.edu [mailto: > histonet-boun...@lists.utsouthwestern.edu] On Behalf Of Shaw, Sharon > Sent: Thursday, January 27, 2011 10:39 AM > To: histonet@lists.utsouthwestern.edu > Subject: [Histonet] Rat Skin > > Can anybody share their protocol on processing rat skin I seem to be having > a problem with it being under processed. I fix the tissue for 11hrs in zinc > formalin and then run a 12 hour processing schedule the skin size is > 2.5cmx1cm. > > Thanks, > Sharon > > _______________________________________________ > Histonet mailing list > Histonet@lists.utsouthwestern.edu > http://lists.utsouthwestern.edu/mailman/listinfo/histonet > The information transmitted is intended only for the person(s)or entity to > which it is addressed and may contain confidential and/or legally privileged > material. Delivery of this message to any person other than the intended > recipient(s) is not intended in any way to waive privilege or > confidentiality. Any review, retransmission, dissemination or other use of , > or taking of any action in reliance upon, this information by entities other > than the intended recipient is prohibited. If you receive this in error, > please contact the sender and delete the material from any computer. > > For Translation: > > http://www.baxter.com/email_disclaimer > > > _______________________________________________ > Histonet mailing list > Histonet@lists.utsouthwestern.edu > http://lists.utsouthwestern.edu/mailman/listinfo/histonet > _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet