Polyamine cytochemistry: comparisons between cytochemical, autoradiographic, immunocytochemical and chemical results...

Results obtained with two newly developed fluorescence cytochemical methods for detecting the polyamines spermidine and spermine have been compared to autoradiographic localization of biosynthetically labelled polyamines, to immunocytochemical results obtained with antibodies directed against spermidine and spermine, and to chemical polyamine determinations using the rat prostate as a model tissue. Complete agreement between all five methods was obtained. Application of perchloric acid to formaldehyde-fixed sections of rat prostate strongly reduced the o-phthalaldehyde inducible and formaldehyde-fluorescamine inducible fluorescence characteristic of spermidine and spermine. Perchloric acid extracted 40% of tissue-bound polyamines from formaldehyde-fixed tissue sections, and molecules with the physicochemical characteristics of polyamines constituted 80-90% of all fluorescamine reactive molecules extracted. Our results therefore confirm the specificity of the o-phthalaldehyde and formaldehyde-fluorescamine methods for polyamine cytochemistry. As polyamines are strongly implicated in cellular growth regulation and cancer, simple and inexpensive techniques for polyamine histochemistry may be useful for interpreting the biological and pathophysiological roles of these molecules.