Histology & Its Methods of Study: Autoradiography

Question 1

Define Autoradiography

Answer 1

microscopic method of localizing newly synthesized macromolecules in cell/tissue sections

• a technique to visualize the distribution of radioactively labeled molecules in biological samples. The sample is exposed to photographic film or a detector that captures emitted radiation, creating an image that shows the location and concentration of the labeled substances

Question 2

What function do radioactively labeled metabolites play?

Answer 2

-metabolites (nucleotides, amino acids, and sugars) are provided to living cells
- they are incorporated into specific macromolecules (DNA, RNA, protein, glycoproteins, and polysaccharides)
- emit weak radiation restricted to regions the molecules are located
- This process localizes cell components synthesized using radioactive precursors by detecting silver grains produced by weakly emitted radiation in a photographic emulsion coating the tissue section or cells.
- With either light microscopy or TEM, autoradiography permits unique studies of processes such as tissue growth (using radioactive DNA precursors) or cellular pathways of macromolecular synthesis.