Yes, it is embedding, not encasing. That's why you use the longer processing schedule for larger tissues. Brains and spines typically require longer processing schedules than other tissues due to the higher fat levels because of the myelin. For whole mouse and rat brains, so long as they are properly fixed, process on average for about 1.5 hours per station. Works like a charm, no issues. Typical (trimmed in) brain sections can get by on about 45 minutes per station. I have even had to process whole large animal organs, of course this was under a hood and took several days to complete, but......
And, no, not all animal researchers perfuse. Quite often, the brain is removed prior to fixation. And depending on what is to be done with the slides after sectioning, frozens are not ideal. Morphometry may be altered, etc. It all depends on the desired end result. Sincerely, Catherine Simonson, HT (ASCP) The Jackson Laboratory Bar Harbor, ME On Mon, Apr 13, 2015 at 10:19 AM, Scouten, Charles < [email protected]> wrote: > Are you really embedding, or just encasing? I have heard that paraffin > cannot penetrate that deeply, that small sections are necessary for the > paraffin to infiltrate the entire piece. Is this not true? > > Why not use frozen sections? You can encase the brain in premade gelatin > molds see this link: > > http://www.leicabiosystems.com/research/neuroscience/tissue-sectioning/details/product/leica-brain-blocker-one/ > and section gelatin and all. Every brain in the same plane of section. > > Do you use fixation perfusion, or just extract the soft brain? Animal > researchers routinely use perfusion for the better tissue quality. > > Cordially, > > Charles W. Scouten, Ph.D. > Applications Specialist > Leica Biosystems > [email protected] > http://www.myneurolab.com > Ph. 630 964 0501 > Cell 314 724 5920 > > > -----Original Message----- > From: [email protected] [mailto: > [email protected]] On Behalf Of Catherine Simonson > Sent: Friday, April 10, 2015 12:38 PM > To: [email protected] > Subject: [Histonet] RE: whole mouse brains > > Hey there! > > I embed whole mouse brains on a regular basis. First, process on a longer > schedule (about 1 to 1.5 hours per station, really. Otherwise they are > under processed and will not cut well and you will have problems getting > them to stay on the slides during staining). Use the deep molds. Keep in > mind that the tissue will shrink (about 20 - 30 %) during processing so > they WILL fit for coronal sections. If need be, trim some of the olfactory > bulbs off (you probably would be facing those off on the microtome anyhow). > > Hope this helps, > > Catherine Simonson, HT (ASCP) > The Jackson Laboratory > Bar Harbor, ME > _______________________________________________ > Histonet mailing list > [email protected] > http://lists.utsouthwestern.edu/mailman/listinfo/histonet > Please be advised that this email may contain confidential information. If > you are not the intended recipient, please notify us by email by replying > to the sender and delete this message. The sender disclaims that the > content of this email constitutes an offer to enter into, or the acceptance > of, any agreement; provided that the foregoing does not invalidate the > binding effect of any digital or other electronic reproduction of a manual > signature that is included in any attachment. > _______________________________________________ Histonet mailing list [email protected] http://lists.utsouthwestern.edu/mailman/listinfo/histonet
