Haut und Epithel, Verschiedenes

Abstract

In the skin of Bombinator pachypus fixed with formol can be observed two types of granulous glands containing either large or small granules which differ both histochemically and histophysically. The acetone extracts of the skin contain a high concentration of 5-hydroxytryptamine and also another substance which couples with diazonium compounds. In material prepared by freeze-drying, the large granules show a complex structure, being composed of numerous minute granules immersed in a homogeneous mass of different reactivity. In addition to the properties already mentioned, these granules react positively in the p-dimethylaminobenzaldehyde reaction, the Morel and Sisley reaction and the blockable PAS reaction. — The fluorescence excited by Wood’s light reveals differences between granular types, between granules themselves and also variations dependent on the fixing process. The spectral curves have been obtained using a Zanotti universal histophotometer. The large granules show strong white-blue primary fluorescence which is increased by post-fixation but is more intense than that of the formol-fixed material; the spectral curves vary in the same way. The small granules show a slight yellow-brown primary fluorescence; post-fixed material and that fixed directly in formol show a fairly intense yellow-gold fluorescence and modified spectra. The fixing process appears to influence the intensity and peak distribution in the UV absorption spectra of the two granular types which accords with the data obtained from fluorescence. The results indicate the complexity of the secretion.