A. E. F. H. Meijer

Semipermeable membranes for improving the histochemical demonstration of enzyme activities in tissue sections

SummaryAn improved histochemical technique for the demonstration of acid phosphatase in tissue sections is described. With this technique a semipermeable membrane is interposed between the incubating solution and the tissue sections preventing diffusion of enzyme into the medium during incubation. Moreover fixation of the tissue sections in order to minimize enzyme diffusion and that causing a partial inactivation of the enzyme, is no longer necessary. In the histochemical system the enzyme catalyzes the hydrolyzes of naphthol AS-BI phosphoric acid. The enzyme localization is visualized by means of simultaneous coupling of the released naphthol with hexazotized pararosanilin. Problems involved in the histochemical demonstration of the enzyme are discussed.

Histochemical method for the demonstration of myosin adenosine triphosphatase in muscle tissues

SummaryA method for the histochemical demonstration of the activity of myosin adenosine triphosphatase in muscle tissues is described. In the histochemical system the enzyme catalyzes the hydrolysis of ATP to ADP and inorganic phosphate. The incubation medium contains Ca2+-ions as activator. The enzyme localization is visualized by means of PbS. Problems involved in the histochemical demonstration of the enzyme are discussed.

The immunohistochemical detection of prostatic acid phosphatase: its possibilities and limitations in tumour histochemistry.

SummaryThe immunological specificity of the Amsterdam rabbit antiserum against human prostatic and phosphatase was studied on paraffin sections of 200 prostatic carcinomas and 330 control tissues using an indirect peroxidase technique. Peripheral blood leucocyte smears were also investigated with a fluorescent technique. In a limited number of cases, the mixed aggregation immunocytochemical method was also applied as post-primary incubation procedure. The diaminobenzidine (DAB) final reaction product of the peroxidase technique, carried out under standard conditions, was quantified in some cases using the Leyden Television Analysis System (LEYTAS) with a built-in standard.A positive reaction was obtained in 96.5% of the prostatic carcinomas. Only 2.1% of the non-prostatic tumour cases (23 types) showed a positive reaction, namely six out of 10 insulomas and one out of 10 carcinoid tumours. The β-cells of the normal islet of Langerhans and the leucocytes in the smears showed a positive reaction. The sensitivity of the peroxidase method, judged subjectively, is not only dependent on the circumstances of fixation, embedding and incubation but also on the degree of tumour differentiation. None of the three prostatic carcinomas studied reached the level of DAB staining intensity shown by the hyperplastic prostatic epithelium.

The histochemical characterization of the coupling state of skeletal muscle mitochondria

SummaryIsolated mitochondria from skeletal muscles of human and animals with neuromuscular diseases may reveal a loosely coupled state of oxidative phosphorylation, which is characterized by a normal phosphorylation in the presence of a phosphate acceptor and a maximal respiration in the absence of a phosphate acceptor. Moreover in these cases activity of mitochondrial Mg2+-stimulated ATPase is strongly increased and cannot be stimulated by the uncoupler 2,4-dinitrophenol. In this communication a histochemical technique for the demonstration of activity of mitochondrial Mg2+-stimulated ATPase to characterize the coupling state of muscle mitochondria in tissue sections, is described. This tissue-saving technique is especially suitable for the study of human skeletal muscle diseases.

Improved histochemical method for the demonstration of the activity of α-glucan phosphorylase

SummaryThe activity and localization of α-glucan phosphorylase in experimental canine glycogen-depleted heart tissue has been investigated with biochemical and histochemical methods using dextran as enzyme acceptor. Only linear, essentially unbranched, dextrans exhibit acceptor properties; highly branched dextrans are not suitable acceptors for the enzyme. Results of Michaelis-Menten constant measurements for the linear essentially unbranched dextran fractions used, indicate that the affinity of the enzyme for the non-reducing end group of the dextran molecule increases with increasing molecular weight of the acceptor.In the glycogen-depleted tissue of anoxic and ischaemic cardiac musculature there is a gradual inactivation of the enzyme during the ischaemic period. Shortly before total inactivation the affinity of the enzyme, especially for the lower molecular dextran fractions, is greatly reduced. Therefore, for the histochemical demonstration of phosphorylase activity in infarcted areas of the heart it is essential to use as acceptor an unbranched dextran fraction with a high average molecular weight.

The influence of freezing and freeze-drying of tissue specimens on enzyme activity.

SummaryIn the presented study the influence of freezing and freeze-drying on enzyme activity is described. Attention is paid to 16 enzymes which can be used for quantitative enzyme histochemical techniques.With the exception of succinate dehydrogenase only, no significant inactivation during freezing and freeze-drying procedures could be demonstrated with lactate dehydrogenase, malate dehydrogenase (NAD+), malate dehydrogenase (decarboxylating) (NADP+), isocitrate dehydrogenase (NADP+), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, NADH-oxydoreductase, mitochondrial glycerol-3-phosphate dehydrogenase, cytochrome c oxidase, phosphoglucomutase, glucosephosphate isomerase, glucose-6-phosphatase, acid phosphatase, β-glucuronidase and non specific aryl esterase. Therefore the results supply a sound foundation for those quantitative enzyme histochemical techniques in which tissue specimens are frozen or frozen-dried before enzyme estimations are performed.

The increase in activity of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in skeletal muscles of rats after subcutaneous administration of N,N′-dimethyl-para-phenylenediamine

SummaryAfter subcutaneous administration of N,N′-dimethyl-para-phenylenediamine (DPPD) in rats, a myogenic myopathy was produced in the skeletal muscles. In this communication, the results of the application of various histochemical techniques for the localization of oxidoreductases, transferases, hydrolases and isomerases and biochemical techniques for the estimation of activities of oxidoreductases in the experimental skeletal muscles are presented. The most striking result was the activity of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase which increased dramatically during the early phase of the muscle disease. The increase in activity of the pentose phosphate shunt enzymes was the first pathological alteration and was present as early as 8 h after a single injection of DPPD. Histochemical techniques for demonstration of activity of both enzymes are therefore highly suited for the detection of minor diseases and the early onset of major diseases of the neuromuscular system. Some glycolytic enzymes as well as some enzymes of the aerobic part of the metabolism showed an early decrease or increase in activity indicating a metabolic imbalance in the muscle fibres. There were more fibres with an intermediate pattern of the energy yielding enzymes in the experimental muscle specimens then in specimens from the control groups. The activity of the catabolic hydrolytic enzymes was strongly increased in pathological muscles. The aerobic muscles were more vulnerable to DPPD than the anaerobic muscles.

Histochemical characteristics of chemoreceptor organs (Glomera)

SummarySome important histochemical characteristics of the carotid, aortic and coronary glomera have been studied in man and the rabbit.All glomera present a similar histochemical pattern. Type I glomus cells contain acetylcholinesterase, monoamine oxidase and norepinephrine. Type II glomus cells are highly positive for cholinesterase, carbonic anhydrase and nucleoside phosphatases hut they do not contain acetylcholinesterase nor catecholamines. It is postulated that the type I glomus cell is the true chemoreceptor cell. Together with the type II glomus cell, which is considered to be a special type of glial cell, a functional metabolic unit is established. Efferent nerve fibres could be adrenergic; by way of cholinergic transmission action potentials could be initiated in the afferent nerve fibres.

The increase in activity of acid hydrolases in muscles of rats after subcutaneous administration of dimethyl-para-phenylene diamine. A combined histochemical and biochemical investigation

SummaryThe activity of acid hydrolases in skeletal muscles of normal rats and of rats after subcutaneous administration of dimethyl-para-phenylene diamine (DPPD) was studied with a combined histochemical and biochemical investigation. In this communication the histochemical findings are presented. After 4 days of DPPD treatment, coagulation necrosis, fragmentation and disintegration of fibres were seen in the muscles. An inflammatory infiltrate was seen between the muscle fibres. These pathological changes reached maximum intensity after 7 to 9 days. After 11 days the changes became less, despite continued treatment with DPPD.From the histochemical findings it appeared that the activity of acid phosphatase, β-glucuronidase and E600 resistant non-specific esterase was increased in both a granular and a diffuse pattern in the skeletal muscles of the DPPD rats. The increase in activity of leucine aminopeptidase was much less pronounced and was mainly granular. The increase in the activity of acid hydrolases ran parallel to the severity of the pathological changes and reached a maximum after 7 to 9 days of DPPD treatment. The statistical calculations of the histochemical findings revealed that the increased activity of one acid hydrolase was significantly paralleled by an increased activity of a second hydrolase. There was a moderate probability that the activity of all other histochemically studied acid hydrolases, with the exception of leucine aminopeptidase, was increased. There was no difference in activity and localization of the acid hydrolases studied in aerobic type I and anaerobic type II fibres. The localization of acid phosphatase and β-glucuronidase activity in muscle fibres and in inflammatory infiltrate mostly coincided. In cases where these enzymes were localized both centrally and in the subsarcolemnal areas of the muscle fibres, the activity of E600 resistant non-specific esterase was usually, and the activity of leucine aminopeptidase was exclusively located in the subsarcolemnal areas. All of the acid hydrolases examined were found to be present in the inflammatory exudate and in the connective tissue.

The value of enzyme histochemical techniques in the classification of fibre types of human skeletal muscle

SummaryIn the present investigation the results of a lead salt technique and two calcium salt techniques for the demonstration of the activity of myosin adenosine triphosphatase in sections of both normal and pathological human skeletal muscle specimens are compared. It was seen that the histochemical results obtained by the different techniques are similar, especially with regard to the identification of fibre-types.It can be clearly stated, that the alkaline phosphatase activity present in muscle fibres of diseased skeletal muscles revealed only a very slight activity with the substrate ATP, so the alkaline phosphatase activity in general did not disturb the reliability of the different myosin ATPase techniques.Moreover it was found that the presence of the mitochondrial Ca2+-ion activated ATPase with a high pH-optimum in muscle fibres did not give rise to faulty results.From studies with dinitrophenol it can be concluded that this substance activates the myosin ATPase present in type I fibres especially.