Freezing microtome

Figure 4. Microautoradiographs of freezing microtome cross sections through a spring whejj embryo and the primary leaf tip after seed dressing with [ C]Baytan (dark-field micrograph).

After surgery, the animals were deeply anesthetized and decapitated, and their brains were frozen on dry ice within 3 min of decapitation. For the coronal plane, brains were divided into two blocks at a plane 3.0 mm anterior to the interaural line prior to placement on the freezing microtome stage. At the level of the blocking some sections were lost and it was necessary to insert three plates (Figs. 42-44) from another brain. 

Fig. 4.8 Freezing microtome. To cut thick frozen sections of 15-50 (rm, a freezing microtome will do the job. The cryoprotected tissue is frozen in O.C.T. on the chuck with hquid CO2, a knife is brought across the tissue, and the section is collected with a small paint brush and placed in a tray...

Floating section immunocytochemistry - performed on free-floating, thick section (25-100 mm) cut on a Vibratome or freezing microtome with antibodies penetrating deeper because of the greater movement of the section floating both sides of the section will be exposed to the antibodies. 

Freezing microtome - used for cutting 15- to 50-p.m thick sections of fixed tissue after infiltrated with 20% sucrose and quickly frozen with liquid CO2 sections are for floating incubations. 

Cut sections using a cryostat or freezing microtome. Sections should be 5-20 pm thick. 

Thereafter, the brain is fixed by perfusion with PBS followed by 4 % buffered PFA. The perfusion is carried out under deep anesthesia (ketamine, 100 mg/kg i.p.), through the ascending aorta. The brain should be carefully removed, post-fixed for 2—4 h in the same fixative at 4 °C, and stored in PBS at 4 °C until the histological procedure is carried out (r Sect. 3.1.3). If you plan to cut the tissue on a freezing microtome, an intermediate step of... 

Histology Cut the brain on the freezing microtome or on the vibratome into... 

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