Our knowledge of chromaffin tissue has increased enormously since the
last comprehensive treatise in this series was published in 1943,
chiefly as a result of the development of new histological methods and
technical improve- ments. Less than 40 years have passed since the
review by MAX WATZKA, and essentially only 25 years were required to
accumulate an abundance of revolu- tionizing findings: it was not until
1957 that the carotid body was first studied successfully with the
electron microscope. In 1962 the technique of formalde- hyde-induced
fluorescence was introduced, yielding a view of adrenergic struc- tures
that was completely new and far better than that obtained with the chro-
maffin reaction. Immunohistochemistry made it possible to localize
enzymes responsible for catecholamine synthesis and to detect peptide
hormones. Autora- diographic techniques were used at the level of the
electron microscope, the method of chemical sympathectomy was introduced
and still other technical improvements could be mentioned. I myself have
been interested in chromaffin cells and sympathetic neurons since 1965,
when I entered the Department of Histology, University of Vienna, as a
medical student. Therefore I have not followed the developments
mentioned above retrospectively, but have actually experienced them.
Anyone who experi- ences such a development comes to believe that he is
well acquainted with the various results and interpretations and is thus
capable of objectivity.