Emulsion autoradiographic

Fig. 3. Distribution of 81 (A) and 82 (B) subunit mRNA in the adult rat brain (X-ray film autoradiographs, horizontal sections) (C), localization of 82 mRNA in cerebellar Purkinje cells (emulsion autoradiograph). Cb, cerebellum Ctx, neocortex Gr, granule cells H, hippocampus Mol, molecular layer P, Purkinje cells arrowheads mark labelled Purkinje cells. Scale bar in B, 3.5 mm scale bar in C, 28 pm (Lomeli et al., 1993).

Fig. 12. The distribution of GluR-A flip and flop mRNAs in the adult rat neocortex (emulsion autoradiographs). (A), Nissl stain (B), GluR-A flip ((7), GluR-A flop. Roman numerals indicate cortical layers. Arrows indicate examples of labelled cells. A strong band of flip-expressing cells is present in layer II of panel B (Wisden and Seeburg, unpublished).

Fig. 14. Expression of the NMDA receptor NR2 subunit mRNAs in the dentate gyrus of the adult rat hippocampus (emulsion autoradiographs). DG, dentate granule cells arrows indicate examples of labelled cells. (Monyer et al., 1992, 1994). Scale bar, 50 p,m.

Do not store bottled autoradiographic emulsions in a freezer Do not keep emulsions longer than 1 or 2 d at room temperature Use meticulously cleaned glassware emulsion coats on glassware and are difficult to remove... 

Protocol updated from Krolak et al. (49) and Dashek and Mills (50). Controls (a) Germinate pollen without [14C]-pro and process as before, (b) Construct a radioautographic sandwich with collodion lacking pollen, (c) Expose a slide coated with Kodak NTB-2 Nuclear Track Emulsion to light and develop emulsion with D-19. (Sample autoradiographs are presented in Fig. 3.)... 

Administration of Radioisotopes, Tissue Preparation, and Emulsions Resolution and Quantitative Autoradiography Limitations of EM Autoradiographs Protocols Conclusions References... 

The reader is referred to Evans and Callow (3) for a discussion of efficiency, i.e., the number of silver grains in the developed emulsion relative to the number of disintegrations occurring in the specimen during exposure. These authors present data representing estimates of efficiency values for tritium in EM autoradiographs. 

Polished sections and polished thin sections are prepared according to the usual techniques of coal petrography. They are mounted permanently on quadrangular pieces of transparent Lucite for location purposes. We have described elsewhere a graphical method of micro-surveying which allows an observer to locate any specific autoradiograph on nuclear emulsion plate of a given point in an opaque section (13). 

The sensitivity and resolution of an autoradiograph depend on the emulsion used. Emulsions come in two forms (a) as a gel which needs to be melted and diluted for use by a dipping procedure, and (b) as a preformed sheet which needs to be stripped from a glass plate, floated on a water surface and transferred to the specimen. 

Fig. 12.5. Effect of length of autoradiographic exposure on grain count. BHK21/C13 cells labelled with [3H]uridine were covered with Ilford L4 emulsion (diluted with an equal volume of water) dried in a horizontal position and exposed in air at room temperature for the indicated times. (Courtesy of K. Shaw and Dr. J.D. Pitts.)...

Autoradiographs may be obtained by pressing a photographic plate or film on the surface of the sample or by the stripping-film or liquid emulsion techniques. 

In one sorption experiment, the particle size distribution of the aqueous plutonium was determined by the centrifugation technique previously described (I). Simultaneously, a study was made of the size distribution of plutonium sorbed onto silica plates by an autoradiographic method (I, 2, 3). After the plutonium sorbed on the silica plates, the latter were dried and clamped for 2 to 4 days to glass plates coated with Kodak NTA nuclear emulsion. After developing the emulsion, the result-... 

After suitable autoradiographs have been generated (which may entail more than one exposure) the slides can be dipped in nuclear emulsion if quantification of probe binding at the single cell level is required (see Note 24). 

Successful application of this technique requires a thin sample and thin photographic emulsion in intimate contact with each other (Figure 14.5). A leaf soaked in Na2H P04 solution will produce a good picture by this method. Autoradiographic techniques are utilised in the analysis of nucleic acids and in DNA fingerprinting (Section 14.3). 

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