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[Methods of the histochemical detection of biogenic amines (author's transl)]
Abstract:
Histochemical and ultrahistochemical methods for the demonstration of biogenic amines are investigated with regard to their efficiencies and limitations. For the purposes of the light microscopy fluorescent histochemical methods at present are sufficient. Hereby beta-arylethyl-amines and indolalkylamines are demonstrable with formaldehyde or glyoxylic acid whilst histamine is traceable with o-phthaldialdehyde. In this connection those chemical and physical conditions of this methods are shown, under which the demarcation and quantitative determination of the several amines is possible. Ultrahistochemically biogenic amines can be demonstrated by means of the chromaffine and the argentaffine reaction, the reaction with permanganate and the REINECKE-salt precipitation technique. Apart from the latter one, all these methods are based on an initially reaction between glutaraldehyde and amines. Thus these techniques might be founded on one and the same principle. Besides, the demonstration of adreanline as a secondary amine might be hindered also by the fact that the product of its reaction with glutaraldehyde is soluble in water. On the other hand the reaction product of primary amines with glutaraldehyde is insoluble in water. When using REINECKE-salt the correctly localizated precipitation of amines is the first step of the reaction. After that the treatment with glutaraldehyde is only serving for the fixation of the tissues. But the ultrahistochemical methods mentioned above altogether are showing a deficiency as far as they do not allow to make the several amines selectively visible. Therefore a quantitative ultrahistochemistry of biogenic amines is still impossible at present.