AUTORADIOGRAPHY 



333 



for gross sectioning of rat bones. An embedding procedure has been 

 described by Arnold (21b). 



The following is a procedure described by Lotz, Clallimore, and Boyd 

 (23) for the preparation of large autoradiograms from undecalcified bones: 



1. The freshly excised bone is cleaned of excess tissue and is mounted 

 on a soft board using Duco cement, care being taken to align the longitu- 

 dinal axis of the bone parallel with the straight edge of the board. 



Fk;. 7-1. Glove box hou.sing band saw for sectioning bones. A viewing window above 

 the glove ports is provided and a vacuum cleaner is used to maintain sliglit negative 

 pressure. [From \V. E. Lotz, J. C. Gallimore, and George A. Boyd, How to Get Good 

 Gross Autoradiographs, Nucleonics, 10: 28-31 (1952).] 



2. To avoid contamination by bone dust, a band saw is housed in a 

 glove box (see Fig. 7-1). Metal cutting blades, }^i in. wide with 15 teeth 

 to the inch, have been found suitable. The guide is adjusted for the 

 desired thickness of section (about 2 mm), and the bone is fed to the blade 

 with a slow uniform motion. 



3. The sections are cleaned of bone particles. Under safelight condi- 

 tions a thin piece of cardboard is placed in a Kodak X-ray exposure 

 cassette. On this is placed the bone section, then an 0.8-mil sheet of 

 Pliofilm to prevent chemical fogging, and then the film. The cassette is 

 closed and held in a plywood press with a piece of sponge rubber inserted 



