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R Gossrau

Publications and source records attributed to R Gossrau.

At least 91 records · Page 5Linked to original sources
PubMed1988

Protease histochemistry in normal and uremic rats.

In rats, ARF caused protease changes which could be detected histochemically. The organs which clearly responded were the extraorbital gland, thymus and lung (ARF-sensitive organs); the others did not show a clear-cut response (ARF-insensitive organs). In the affected organs activities of plasma membrane-associated and lysosomal proteases were either increased or decreased. The response of the proteases in the extraorbital gland is considered to be specific whereas this in the thymus and lung is not. However, ARF has not a protease-specific effect which can be shown when further groups of enzymes are investigated using histochemical means.

Acute Kidney Injury↗
PubMed1988

Plasma membrane proteases as useful tool in histochemical toxicology.

Compared with mitochondrial, lysosomal and endoplasmic reticulum enzymes and plasma membrane-associated hydrolases plasma membrane-linked proteases in the rat thyroid gland, liver, kidney, placenta and yolk sac were more easily affected after the administration of the drugs salicylic acid and dexamethasone. Either a decrease or an increase of protease activity was observed in the surface membrane of capillary endothelial cells, hepatocytes, fetal placental cells and visceral yolk sac epithelial cells whereby proteases being localized in the same domain of the plasma membrane showed a different response.

Animals↗
PubMed1988

Dipeptidyl peptidase (DPP) IV in rat organs. Comparison of immunohistochemistry and activity histochemistry.

Immunohistochemistry and activity histochemistry were used to study the localization of dipeptidyl peptidase (DPP) IV in rats. For immunohistochemistry, polyclonal as well as monoclonal anti-DPP IV antibodies were employed. The pattern of DPP IV immunoreactivity, determined with polyclonal anti-DPP IV antibody, corresponds to the histochemical pattern found for the enzymic activity of DPP IV. Immunoreactivity was present, in addition, in nerve cells, lateral membranes of certain surface epithelia, e.g., Fallopian tube, uterus and vesicular gland, in the luminal cytoplasm of e.g., vesicular gland epithelium, and in mucous cells of Brunner's gland. The monoclonal antibodies against DPP IV recognized four different epitopes (A-D) of the DPP IV molecule, and revealed that certain epitopes were not detectable by immunohistochemistry in some organs. Generally, the staining intensities for epitopes A, B, C and D decreased in that order. Usually, the monoclonal antibodies against epitopes A and B showed similar reaction patterns to those as obtained with the polyclonal antibody. Epitope D was recognized in the lumen of the duct system of exocrine glands and the intestine. Furthermore, high reactivity of this epitope was detected in goblet cells of the intestine, where no DPP IV activity was present.

Animals↗
PubMed1988

Light-microscopic histochemistry of non-specific alkaline phosphatase using lanthanide-citrate complexes.

New lanthanide methods for the histochemical detection of non-specific alkaline phosphatase in the light microscope are described and compared with already existing techniques for the light microscopical demonstration of this enzyme. To avoid formation of insoluble lanthanide hydroxide at alkaline pH citrate complexes with the capture ions cerium, lanthanum and didymium were used. A molar ratio of 11 mM citrate/14 mM capture reagent is proposed. For preincubated sections, pretreatment in chloroform-acetone and fixation in glutaraldehyde, for non-preincubated sections fixation in glutaraldehyde yielded the best results. 4-Methylumbelliferyl and 5-Br-4-Cl-3-indoxyl phosphate were found to be the most suitable substrates. For routine purposes 4-nitrophenyl, 1-naphthyl, 2-naphthyl and 2-glycerophosphate were also sufficient; naphthol AS phosphates were inferior but still suitable. After incubation for 5-60 min at 37 degrees C lanthanide phosphate was converted into lead phosphate which was visualized as lead sulfide. At pH 9.2-9.5 enzyme activity was demonstrated at many sites such as intestinal, uterine, placental, renal and epididymal microvillous zones, plasma membranes of arterial, sinus and capillary endothelial cells, vaginal and urethral epithelium, smooth muscle cells, myoepithelial cells as well as excretory duct cells of salivary and lacrimal glands and in secretory granules of laryngeal glands. In comparison with Gomori's calcium, Mayahara's lead, Burstone's and Pearse's azo-coupling, McGadey's tetrazolium salt and Gossrau's azoindoxyl coupling technique the lanthanide methods detected alkaline phosphatase activities at identical or additional sites depending on the respective procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMed1988

The cerium perhydroxide-diaminobenzidine (Ce-H2O2-DAB) procedure. New methods for light microscopic phosphatase histochemistry and immunohistochemistry.

New light microscopic visualization methods were developed for the histochemical detection of non-specific alkaline and acid phosphatase, Mg-, Ca- and Na, K-dependent adenosine triphosphatase, myosin adenosine triphosphatase, glucose-6-phosphatase, 5'-nucleotidase and thiamine pyrophosphatase with cerium ions as trapping agents in cryostat and plastic sections. The techniques are based on the conversion of cerium phosphate into cerium perhydroxide by H2O2 which decomposes at 55 degrees-60 degrees C into cerium hydroxide and oxygen radicals. These radicals are able to oxidize diaminobenzidine (DAB) to DAB brown. Addition of nickel ions to the DAB-H2O2 mixture generates bluish-black stained nickel-DAB complexes. Compared with the classical metal precipitation, azo, azoindoxyl and tetrazolium procedures the H2O2-DAB and especially the H2O2-DAB-nickel methods provided identical or superior results in catalytic phosphatase histochemistry and immunohistochemistry when using non-specific alkaline phosphatase as the enzyme label.

3,3'-Diaminobenzidine↗
PubMed1988

Enhancement of maternal and fetal nephrotoxicity of salicylate by zinc deficiency. Morphological, enzyme histochemical and immunohistochemical studies.

An oral dose of 700 mg/kg salicylic acid was given to normal and Zn-deficient rats at day 16 of gestation. Maternal and fetal kidneys were studied at day 19 of gestation. Zn-deficiency did not cause any lesions detectable by semi-thin section light microscopy, electron microscopy, enzyme histochemistry and immunohistochemistry. Salicylate may lead only to small morphological, enzymatic and cytoskeletal defects in the maternal and fetal kidney. However, enzyme activities decreased in plasma membranes, mitochondria, lysosomes, endoplasmic reticulum and peroxisomes in all segments of the tubular apparatus when salicylate was given to Zn-deficient rats. Cytoskeletal proteins such as keratin in the glomerular cells and epithelial lining of the collecting ducts and vimentin in vascular endothelial cells of the maternal kidney were also affected. In addition, the epithelial cells of the collecting ducts, which were comparatively less damaged, accumulated high amounts of fat. In severe cases, the enzymatic and cytoskeletal lesions were accompanied by hematuria and tubular necroses including and collecting ducts in the renal papilla. In less severe cases reduced activities of brush border hydrolases were the only sign of disturbed renal function in maternal rats indicating that membrane alteration and loss of membrane-bound enzymes are the primary defects. In the fetal kidneys, mitotic activity of the cells of the nephron anlagen and collecting ducts was reduced and enzymatic and morphological differentiation were disturbed. As a consequence less mature nephrons and collecting ducts occurred.

Animals↗
PubMed1988

Enzyme cytochemistry of rat organs after uremia with special reference to proteases.

Wistar rat organs and tissues were investigated after acute and chronic uremia using enzyme cytochemical means whereby special attention was paid to plasma membrane and lysosomal proteases. Heart muscle, pancreas, spleen, stomach, duodenum, jejunum, colon and skeletal muscle did not show any clear-cut indications of alterations. After acute uremia activities of dipeptidyl peptidase IV, glutamyl aminopeptidase and microsomal alanyl aminopeptidase were decreased in the extraorbital gland and that of dipeptidyl peptidase IV in the submandibular gland. The thymus showed an increased staining for glutamyl aminopeptidase and lysosomal proteases. An activity increase of dipeptidyl peptidase IV, acid phosphatase and beta-N-acetyl-D-glucosaminidase occurred in bronchial lavage cells among which the alveolar macrophages predominated. In addition, their number was comparatively higher. Non-specific esterase activity was lowered in these cells. Alkaline phosphatase activity was drastically enhanced at the biliary pole of hepatocytes. Following chronic uremia all effects were less pronounced except for the lavage cells which were positive for glutamyl aminopeptidase, microsomal alanyl aminopeptidase and gamma-glutamyl transpeptidase and showed increased staining for lysosomal proteases, glycosidases and nonspecific phosphatases.

Aminopeptidases↗
PubMed1988

Maternal and fetal iron accumulation in Zn-deficient and salicylate-treated rats.

Nonhemoglobin Fe (non Hb-Fe) content in fetal serum and liver is much higher than in maternal serum and liver. After feeding a Zn-deficient diet to pregnant rats from d 0 to 21, non Hb-Fe content in maternal and fetal serum and liver was increased. After oral application of salicylic acid (300 mg/kg) from d 16 to 20 to normally fed and Zn-deficient dams, non Hb-Fe content in maternal and particularly in fetal serum and liver was drastically increased. In the kidney, Fe was accumulated to a small amount resulting from Zn deficiency and salicylate treatment. Fe accumulation in the liver occurred in all cell fractions, particularly in microsomes. Fe accumulation was confirmed and extended histochemically by Prussian blue staining. It is assumed that salicylate increases intestinal Fe resorption and fetal transfer of Fe. It is discussed that salicylate nephrotoxicity and its enhancement by Zn deficiency is not caused by an Fe-dependent mechanism.

Animals↗
PubMed1988

Direct evidence for the binding of rat liver DPP IV to collagen in vitro.

Previous studies have shown that the tripeptide Gly-Pro-Ala, a substrate for dipeptidyl peptidase IV (DPP IV, EC 3.3.14.5), interferes with initial spreading of hepatocytes on a matrix consisting of fibronectin and denatured collagen. In the present investigation we report that the tripeptide as well as the anti-DPP IV antibody inhibits the initial spreading of hepatocytes also on native collagen. This effect appears to be due to the interaction of DPP IV from hepatocyte plasma membrane with native collagen. It is shown in vitro by immunohistochemistry, catalytic histochemistry, and by affinity chromatography of solubilized plasma membrane on collagen-Sepharose that DPP IV has a binding affinity to collagen. This binding does not affect the activity of DPP IV.

Animals↗
PubMed1988

[Histochemical studies of human stomach biopsies with special reference to hydrolases].

Peptidases, phosphatases, glycosidases, non-specific esterases, succinate dehydrogenase, cholinesterases, and carbohydrate components were studied in bioptic material of the normal and diseased human stomach using well established older, modified older, and new qualitative histochemical methods. For the first time, an enzyme pattern is reported for all regions of the human mucosa. Local and regional enzyme histochemical differences existed between the cardiac, fundic, body, and pyloric mucosa. Differences were absent, however, in the same region, and no differences were found between the anterior and posterior wall and the large and small curvature of the stomach. In cases of histologically less severe gastritis as a rule, enzyme histochemical changes were not found. They were numerous, however, in biopsies of patients with severe gastritis; only amino-peptidases A and M were unchanged. Dipeptidyl peptidase IV was absent; gamma-glutamyl transpeptidase exhibited individual differences. Alkaline phosphatase occurred in the pericapillary stroma and adenosine phosphates were not hydrolysed in atrophic glandular epithelia. Activity increases of lysosomal dipeptidyl peptidase I and beta-D-glucuronidase were typical for inflammatory infiltration processes of the gastric mucosa. Severe atrophy was accompanied by an activity decrease of glandular non-specific esterases, dipeptidyl peptidase II, and beta-N-acetyl-D-glucosaminidase and an activity decrease of the stromal peptidases and glycosidases. Enzyme activity was absent in the gastric glands proper in cases of total atrophy. An increase in macrophage number was primarily linked with an increase in acid phosphatase activity. Alkaline phosphatase, aminopeptidase M and gamma-glutamyl transpeptidase activities were enhanced in malignant neoplasms. High activities of all peptidases and alkaline phosphatase were found in the brush border of surface epithelial cells in cases of intestinal metaplasia. Except for dipeptidyl peptidase I and II, the enzyme pattern corresponds to that of small intestinal enterocytes. Compared with histological routine procedures for gastric diagnosis and assessment of the course enzyme histochemical methods deliver additional information; practically, however, the enzyme histochemical analysis of gastric biopsies are only useful in special cases.

Biopsy↗
PubMed1987

The basement membrane of the persisting maternal blood vessels in the placenta of Callithrix jacchus.

Formation and morphology of the thickened basement membrane-like layer around the persisting maternal vessels of the Callithrix jacchus placenta were investigated from day 45 until term (day 142) using light, electron and immunofluorescence microscopy. Thickening occurs with the establishment of contacts between the vessels and the syncytiotrophoblast (day 48). Final thickness is reached at about day 100. The course of the vessels shows wide gaps where the maternal blood flows freely into the intertrabecular spaces. As revealed by electron microscopy, the extracellular sheath around the maternal vessels consists of an inner subendothelial basement membrane (3-6 microns) and an outer fibril-containing layer (2-4 microns). Cell debris is seen between the two layers and in the basement membrane. Plaques of granular and fine-filamentous material are incorporated into the fibril-containing layer. The synthesis of the basement membrane material is localized in the endothelial cells. Immunofluorescence microscopy reveals collagen types IV and V, laminin and heparan sulfate proteoglycan (BM-1) in the sheath around the persisting vessels. Fibronectin occurs only in certain areas or in the form of dots. Collagen types I and III are not seen in the region of the vascular wall. It can, therefore, be assumed that the subendothelial layer represents a genuine basement membrane; the fibrils consist of collagen type V and the plaques contain fibronectin. The existence of the thick perivascular sheath is attributed to the persistence and stability of the maternal vessels.

Animals↗
PubMed1987

Enzymatic and morphological response of the thymus to drugs in normal and zinc-deficient pregnant rats and their fetuses.

In the thymus of normally fed pregnant rats the plasma membrane enzymes dipeptidyl peptidase IV (DPP IV) and alkaline phosphatase (alP) were found in cortical and medullary lymphocytes (thymocytes). Plasma membrane aminopeptidase A (APA) and adenosine monophosphate hydrolysing phosphatase (AMPP) were present in cortical reticular cells. In medullary reticular cells, aminopeptidase M (APM), gamma-glutamyl transferase (GGT), adenosine triphosphate (ATPP) and thiamine pyrophosphate (TPPP) cleaving phosphatases were detected. Medullary reticular cells did not contain APA. Lysosomal DPP I and II, acid phosphatase, acid beta-D-galactosidase, beta-D-N-acetyl-glucosaminidase, beta-D-glucuronidase and non-specific esterases occurred especially in macrophages at the corticomedullary junction. The 21-day-old fetal thymus showed a similar reaction pattern as the maternal organ except for APA which was absent before birth. After treatment of the pregnant rats with valproic acid (VPA), salicylic acid (SA), streptozotocin (ST) and retinoic acid (RA) APA showed an increase in activity in the thymic cortex. In addition, ST and RA induced AMPP, ATPP and TPPP activity in cortical reticular cells up to the same pattern as in medullary reticular cells. After ethanol (ET) administration severe damages occurred. The thymic cortex was free of DPP IV-positive lymphocytes; the medullary reticular cells showed reduced or no GGT and occasionally an increased APM activity. Dexamethasone (DEXA) given to normal or zinc-deficient rats produced the most severe lesions; thymocytes with DPP IV activity were completely absent in the cortex and medulla. In Zn-deficient pregnant rats similar alterations were observed as after ET.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Increased expression of a high molecular weight matrix component in rat hepatocellular carcinoma.

The urea extract of the glycoproteins from the extracellular matrix of rat liver has been compared with that of Morris hepatoma 7777. A high molecular weight glycoprotein present in Morris hepatoma 7777 was not found in the extract of liver matrix. Under reducing conditions in SDS-gel electrophoresis this component gave two glycoprotein bands with Mr 53 k and 56 k. The indirect immunofluorescence staining with a monospecific antiserum directed against the component showed its abundant presence in Morris hepatoma 7777 as well as in the less malignant Morris hepatoma 9121 in form of extracellular network structures. The antigen also densely filled some cumuli of cells. In contrast the liver tissue showed only very weak staining of the extracellular areas. The overall distribution of the component could be correlated with the distribution of several hydrolases in the tumor matrix, notably beta-D-glucuronidase.

Animals↗
PubMed1987

Histochemical detection of alpha-D-glucosidases and their molecular forms with 5-Br-4-Cl-3-indoxyl-alpha-D-glucoside.

5-Br-4-Cl-3-Indoxyl-alpha-D-gluco(pyrano)side was found to be the most suitable synthetic substrate for the demonstration of alpha-D-glucosidases in situ. Using an azoindoxyl procedure with hexazotized pararosaniline or new fuchsine at pH 5 in freeze-dried celloidine-mounted cryostat sections acid alpha-D-glucosidase (EC 3.2.1.20) was shown for the first time in lysosomes of many cells of fetal and adult rat, mouse, guinea-pig, marmoset and human organs. At pH 6.5, in chloroform-acetone pretreated cryostat sections plasma membrane alpha-D-glucosidases were shown in the brush border of enterocytes of the small and large intestine, in the brush border of proximal renal tubule cells and in the stereocilia of the epididymal duct. In an indigogenic procedure with ferricyanide/ferrocyanide as redox catalysator plasma membrane alpha-D-glucosidases were depicted as well as with the azo-indoxyl method; the demonstration of the acid alpha-D-glucosidase was inferior to that achieved with the azo-indoxyl procedure. Using tetrazolium salts as capture reagent intracellular localization was unsatisfactory. In enterocytes, a localization in the Golgi apparatus was shown by the azo-indoxyl procedure only. Analytical isoelectric focusing revealed organ-dependent differences of plasma membrane and lysosomal alpha-D-glucosidases. Compared with the already existing methods the azo-indoxyl and indigogenic procedures are by far the most suitable techniques.

Animals↗
PubMed1987

Proteases in the human full-term placenta.

Aminopeptidase A, not yet defined aminopeptidases and endopeptidases, dipeptidyl peptidase I, II and IV, gamma-glutamyl transferase and oxytocinase were investigated in the normal human full-term placenta using qualitative (catalytic) cytochemistry, isoelectric focusing, immunocytochemistry and kinetic fluorometry. Aminopeptidase A could be visualized cytochemically in the smooth muscle cells of the chorionic plate, stem villi and basal plate blood vessels. Aminopeptidases were found in connective tissue fibres of the chorionic plate, villous stroma, basal plate and paraplacenta. Dipeptidyl peptidase IV was detected at the same sites as the aminopeptidases and, in addition, in amniotic epithelial cells, fibroblasts of the villous stroma, endothelium of chorionic plate and villous blood vessels as well as in the basophilic cytotrophoblast cells (x-cells) of the basal plate and paraplacenta, and it possibly also occurred in some domains of the plasma membrane of the syncytiotrophoblast and cytotrophoblast cells. The x-cells surrounded the fetus in the form of a dipeptidyl peptidase IV-positive shell at the border to the mother. The enzyme represented the first specific marker for x-cells. Dipeptidyl peptidase I and II were primarily found in Hofbauer cells (macrophages) of the villous stroma, but also in the syncytiotrophoblast, other villous stromal cells and cells of the chorionic and basal plate. gamma-Glutamyl transferase was present in some connective tissue elements of the chorionic plate. Oxytocinase and endopeptidases were not detected. Isoelectric focusing of proteases revealed different molecular forms of dipeptidyl peptidase IV in the paraplacenta and villous tree, while the aminopeptidases shared the same pattern in both regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminopeptidases↗
PubMed1986

Increased activity of dipeptidyl peptidase IV in serum of hepatoma-bearing rats coincides with the loss of the enzyme from the hepatoma plasma membrane.

The specific activity of dipeptidyl peptidase IV (DPP IV E.C. 3.4.14.-) in the plasma membrane of Morris hepatoma 9121 or hepatoma 7777 was 3.5% and 2.9%, respectively, of that in the plasma membrane of rat liver. The enzyme activity in the serum of hepatoma-bearing rats was 141% (hepatoma 91219) and 162% (hepatoma 7777) of the normal value. Cytochemical investigation showed that the DPP IV activity was almost completely absent from the hepatoma cell plasma membrane and was not sequestered within these cells. Indirect immunofluorescence staining with a polyclonal antibody directed against DPP IV indicated that the loss of activity was due to the absence of DPP IV molecules in the plasma membrane. The possibility that the enzyme is transferred from the membrane into the serum as a result of structural alterations is discussed.

Animals↗
PubMed1986

Protease cytochemistry in the murine rodent, guinea-pig and marmoset placenta.

Plasma membrane and lysosomal proteases, gamma-glutamyl transferase and extracellular matrix proteases were investigated by qualitative cytochemical means in the mature placenta of mice, rats, guinea-pigs and marmosets. These studies revealed similarities, which concerned primarily the lysosomal proteases in different structures of the placenta and all proteases and gamma-glutamyl transferases in the zone of placental shedding. However, species differences predominated. They were observed especially for amino-peptidase A and M, dipeptidyl peptidase IV and gamma-glutamyl transferase in the plasma membranes and extracellular matrix of the placental barrier and decidual cells of all species and the cells of the basal zone in rats and mice. Plasma membrane and extracellular matrix proteases in other parts of the placenta, e.g. the placenta stem of guinea-pigs and basal plate, amniotic and chorionic plate of marmosets occurred only in these species. Elastase substrates hydrolysing endopeptidase I and kallikrein-, thrombin-, plasmin-, plasminogen- and cathepsin B substrates hydrolysing endopeptidase II were not observed in any of these species. A general comparison of the species revealed similarities for the mouse, rat and guinea-pig placental barrier, but not for that of marmosets. The proteases of this zone in the marmoset placenta are more similar to the human situation, but do not correspond to it completely.

Animals↗