Autoradiographic Methods and Principles for Study of the Nervous System with Thymidine-H³

Abstract

The history of autoradiography as a method is closely interwoven with the idea of radioactivity itself. Niepce de St. Victor (1867) and Henri Becquerel (1896) made the first autoradiograms when they showed that uranium salts altered the emulsion in an adjacent photographic plate, though they had formulated the experimental design on the premise that light mediated the response. In 1898 Marie Curie reinterpreted Becquerel’s observations and added the measurements that established the concept of radioactivity (Romer, 1955). Subsequent applications to biological problems followed basically the same technical approach, but histological (microscopic) autoradiography became practical only after several more decades, with the development of methods for maintaining accurate alignment of a thin slice of tissue and a photographic film through the many steps of staining and development, so that a radioactive source could be localized in the tissue by direct microscopy (e.g., Bélanger and Leblond, 1946). The subsequent development of tritium as a tracer, of a range of fine-grained precision emulsions, and of refinements in the methods for applying them to tissue specimens has been reviewed by Caro (1964, 1966), Bélanger (1965), Salpeter (1966), Stevens (1966), and Rogers (1967).