D-Ephedrinephosphate, DEP: a new substrate with specificity for prostatic acid phosphatase (PAP).

This report describes the synthesis and physical (including spectral) properties of a new substrate, D-ephedrinephosphate, DEP1, which is histochemically highly specific for a secreted non-lysosomal prostatic acid phosphatase, PAP. This specificity is in contrast to other substrates which are nonspecific, i.e., which demonstrate acid phosphatases that originate from various cell types and are mainly lysosomal. When this substrate is used for light and electron microscopic histochemistry in a modified Gomori medium, PAP is demonstrated mainly in secretory granules and in the Golgi apparatus (and its related vacuoles) of prostatic epithelial cells of several species of mammals including man. This corroborates our previous suggestion that PAP is not a lysosomal enzyme as are many of the other acid phosphatases. This high degree of specificity of DEP for PAP supports the usefulness of this compound in the histochemical and biochemical characterization of PAP, and in the diagnosis of localized or disseminated prostatic disease.

The histochemical demonstration of human prostatic acid phosphatase with phosphorylcholine.

Tissues from patients with benign prostatic hyperplasia were used for the cytochemical demonstration in light and electron microscopy of a secreted, nonlysosomal prostatic acid phosphatase (PAP) with phosphorycholine, substrate specific for PAP. The specificity of phosphorylcholine for PAP is attributable to the pentavalent nitrogen in phosphorylcholine, a feature that renders it resistant to hydrolysis by all other acid phosphatases. PAP activity was found in the Golgi cisternae and its associated vacuoles and in secretory vacuoles localized in the nuclear, Golgi, and apical areas of the prostatic epithelial cell. These results confirm the existence of two types of acid phosphatase in prostatic tissue. One is lysosomal and is prevalent in many tissues and the other, PAP, is the major enzymatic product secreted by the prostate. The specificity of PAP for phosphorylcholine, one of the natural substrates for this enzyme, validates the use of this method for the histochemical characterization of PAP and indicates the prostatic origin of cells showing PAP activity.

New agents for prostatic cancer activated specifically by prostatic acid phosphatase.

Potential cytotoxic compounds (spindle poisons) are being designed for the treatment of prostatic carcinoma, using the structural requirements of the substrates for prostatic acid phosphatase (PAP). Colchicine has been modified in ring C to give colchiceinamides of substituted ethanolamines and ethanolaminephosphates. Another new series of compounds modifying ring B of thiocolchicine have been prepared. Three O-phosphates of the thiocolchicine series have also been made. One has been examined for its specificity toward PAP. Some toxicity data of these compounds in mice have also been reported. Colchiceinamide-(L)-ephedrinephosphate has been examined in stumptail monkeys and some preliminary results are reported here.

The cytochemical demonstration of prostatic acid phosphatase using a new substrate, phosphorylcholine.

Prostatic acid phosphatase (PAP), an acid phosphatase specific to the prostate gland, is demonstrated cytochemically for both light and electron microscopy with a new substrate phosphorylcholine. Lead ion is used as capture agent for liberated phosphate ion in a modified Gomori medium. PAP is demonstrated in the tubuloaveolar epithelial secretory cells of the rat ventral prostate gland. In the apical portion of the cell it is found in secretory granules and in the matrix of multivescular bodies. In the Golgi area it is localized in Golgi cisternae, Golgi related vacuoles and multivescular bodies. Evidence is presented that PAP is not a lysosomal enzyme, as are other acid phosphatases, and that phosphorylcholine is a highly specific substrate for PAP. As based on the role of pentavalent nitrogen on substrate structure, it is apparent that PAP is to other acid phosphatases what the cholinesterases are to other esterases.

Ultrastructural cytochemistry of p-N,N-dimethylamino-beta-phenethylamine (DAPA) oxidation reactions. "activation" and inhibition studies.

The oxidation of p-N,N-dimethylamino-beta-phenethylamine (DAPA) by amine oxidase(s) (AO), i.e., diamine oxidase (DAO), monoamine oxidase (MAO) and/or possibly other oxidases, has been previously demonstrated. This study reports the results of variations in fixation procedures and the incorporation of a series of possible "activators" and inhibitors into the DAPA oxidase (DAPAO) and DAPAO-BSPT [2-(2'-benzothiazolyl)-5-styryl-3-(4'-phthalhydrazidyl) tetrazolium chloride] reaction media in an attempt to elucidate the oxidase(s) involved. Results of these studies are indicative of at least two different oxidases acting preferentially on one or the other of the two systems. The presence of MAO, especially in unfixed tissue, and DAO, especially in fixed tissue, is denoted and that of other oxidase(s) is connoted.

Ultrastructural cytochemistry of p-N,N-dimethylamino-beta-phenethylamine (DAPA) oxidation reactions.

The ultracytochemical localization of amine oxidase (AO) activity is demonstrated with a new substrate, p-N,N-dimethylamino-beta-phenethylamine (DAPA). DAPA was designed to yield a stronger reducing agent on oxidation by monoamine oxidase (MAO) than is obtained from the MAO substrate, tryptamine, upon oxidation. Thus MAO and possibly other oxidase(s) can be demonstrated with DAPA and the tetrazolium salt, 2-(2'-benzothiazolyl)-5-styryl-3-(4'-phthalhydrazidyl) tetrazolium chloride (BSPT). The latter is a nonosmiophilic tetrazolium salt which is reduced to an osmiophilic formazan. In addition, DAPA itself demonstrates AO activity ultracytochemically with and without BSPT. We speculate that either oxidative polymerization of DAPA or Schiff's base formation with protein after aldehyde formation is responsible for the latter reaction, which is made permanent for ultracytochemical localization by osmication at a later step. DAPA oxidation reaction products are demonstrated in guinea pig kidney, specifically in the endoplasmic reticulum, nuclear envelope and mitochondrial outer compartments and cristae. Differences in reaction product characteristics and localization in relation to formaldehyde fixation and the localization of reaction product in mitochondrial cristae, as well as outer compartments, suggest that DAPA oxidation is mediated through one or more MAOs and possible other oxidases.

The ultracytochemical demonstration of a formaldehyde-resistant dehydrogenase of leuco nitroxyl analogues.

A dehydrogenase which is relatively stable in formaldehyde fixative is demonstrated ultracytochemically by the reduction of various leuco nitroxyl analogues in rat hepatic, renal, myocardial, skeletal muscle and prostatic tubuloalveolar glandular tissues. The nonosmiophilic tetrazolium salt, t-(2'-benzothiazolyl)-5-styryl-3-(4'-phtalhydrazidyl) tetrazolium chloride, is subsequently reduced to an insoluble osmiophilic formazan by the hydrogen ions resulting from the dehydrogenase activity. Exposure of the formazan to osmium tetroxide results in electron density enabling visualization of the reaction product in the electron microscope. Known inhibitors of various dehydrogenases were utilized in an attempt to determine the existence and/or extent of any specific characteristics of the dehydrogenase(s) involved.

A new fluorescent method for the demonstration of macromolecular aldehydes.

The fluorochrome, p-hydrazinoacridine (HA), is used to stain selectively natural macromolecular aldehydes as occur in elastic tissue as well as periodic acid (oxidized) or hydrochloric acid (hydrolyzed) engendered polyaldehydes (e.g., respectively of glycogen, mucosubstances and deoxyribonucleic acid). The reaction is independent of SO2 required in Schiff-type reactions. The mechanism of the staining reaction is presumably via the formation of fluorescent hydrazones from aldehyde condensation with HA. Aldehyde blocking agents, i.e., thiosemicarbazide and sodium borohydride, block the staining reactions with HA. In view of the controversy surrounding the mechanism of Schiff-type reactions and the lack of an adequate explanation for the affinity of miscellaneous fluorochromes for elastic tissue, p-hydrazinoacridine appears to be an ideal reagent, combining a simple staining procedure, excellent histological results and a straightforward mechanism for its selectivity.

Design of spindle poisons activated specifically by prostatic acid phosphatase (PAP) and new methods for PAP cytochemistry.

By taking advantage of the structural requirements of the substrates for prostatic acid phosphatase (PAP), which consist of steric hindrance and the presence of basic nitrogen in the molecule, potential cytotoxic agents (spindle poisons) are being designed that will become enzyme activated specifically by PAP. Colchicine has been converted to colchiceinamides of substituted ethanolamines and o-phosphoethanolamines. The rate of hydrolysis of the latter by human prostatic tissue as compared to the rate of hydrolysis by human kidneys (P/K ratio) is given and indicates a significant degree of specificity for PAP. Some preliminary toxicity data in mice are also given. New thiocolchicine derivatives with phosphates on ring B are also being prepared for study and some preliminary toxicity data are given. The observation in biochemical experiments that phosphorylcholine is a very specific substrate for PAP has led us to develop specific cytochemical methods for PAP for both light and electron microscopy. Preliminary observations are given and good evidence is provided that PAP is not a lysosomal enzyme, unlike other acid phosphatases. Furthermore, PAP is to other acid phosphatases what the cholinesterases are to other esterases. Since the acid phosphatase that is able to hydrolyze phosphorylcholine is characteristic of prostatic epithelium, this is the acid phosphatase that is referred to be the designation of PAP. Other acid phosphatases (both lysosomal and nonlysosomal) in prostatic epithelial cells are not demonstrated by this substrate and hence are not included in this designation.