Selective suppression of endogenous peroxidase activity: application for enhancing appearance of HRP-labeled neurons in vitro

1989 ◽  
Vol 26 (3) ◽  
pp. 181-188 ◽  
Author(s):  
Carol B. Metz ◽  
Stephen P. Schneider ◽  
Robert E.W. Fyffe
Keyword(s):  
Peroxidase Activity ◽  
Selective Suppression ◽  
Endogenous Peroxidase

scholarly journals CYTOCHEMICAL LOCALIZATION OF ENDOGENOUS PEROXIDASE IN THYROID FOLLICULAR CELLS

1970 ◽  
Vol 44 (3) ◽  
pp. 655-666 ◽  
Author(s):  
Judy M. Strum ◽  
Morris J. Karnovsky
Keyword(s):  
Peroxidase Activity ◽  
Apical Cell ◽  
Thyroid Peroxidase ◽  
Follicular Cells ◽  
Cytochemical Localization ◽  
Thyroid Follicular Cells ◽  
Endogenous Peroxidase ◽  
Rat Thyroid ◽  
Vitro Effect

Endogenous peroxidase activity in rat thyroid follicular cells is demonstrated cytochemically. Following perfusion fixation of the thyroid gland, small blocks of tissue are incubated in a medium containing substrate for peroxidase, before being postfixed in osmium tetroxide, and processed for electron microscopy. Peroxidase activity is found in thyroid follicular cells in the following sites: (a) the perinuclear cisternae, (b) the cisternae of the endoplasmic reticulum, (c) the inner few lamellae of the Golgi complex, (d) within vesicles, particularly those found apically, and (e) associated with the external surfaces of the microvilli that project apically from the cell into the colloid. In keeping with the radioautographic evidence of others and the postulated role of thyroid peroxidase in iodination, it is suggested that the microvillous apical cell border is the major site where iodination occurs. However, that apical vesicles also play a role in iodination cannot be excluded. The in vitro effect of cyanide, aminotriazole, and thiourea is also discussed.

scholarly journals DEVELOPMENT OF ENDOGENOUS PEROXIDASE IN FETAL RAT SUBMANDIBULAR GLAND

1973 ◽  
Vol 21 (1) ◽  
pp. 42-50 ◽  
Author(s):  
SHOHEI YAMASHINA ◽  
TIBOR BARKA
Keyword(s):  
Endoplasmic Reticulum ◽  
Nuclear Envelope ◽  
Submandibular Gland ◽  
Rough Endoplasmic Reticulum ◽  
Peroxidase Activity ◽  
Secretory Granules ◽  
Prenatal Development ◽  
Reaction Products ◽  
Cell Type ◽  
Endogenous Peroxidase

The prenatal development of endogenous peroxidase activity in the submandibular gland of rat was investigated by means of the diaminobenzidine-H2O2 histochemical method. The submandibular gland of a 16-day-old fetus was composed of cords of uniform, undifferentiated cells which contained no secretory granules and revealed no peroxidase activity. Peroxidase activity first appeared at the 17th day of gestation in the cisternae of the rough endoplasmic reticulum and nuclear envelope in a few cells. At the 18th day of gestation cells which exhibited reaction products in the rough endoplasmic reticulum and nuclear envelope also contained secretory granules with a strong peroxidase activity. During the last days of gestation the number of peroxidase positive cells, which contained numerous secretory granules, increased. The peroxidase-containing cells are the immediate precursors of the proacinar cells of early postnatal stages. During the same time period, when the peroxidase-containing cells differentiated, a second cell type also differentiated in the cellular cords. The development of this cell type was marked by the appearance of secretory granules stainable with toluidine blue. Through the prenatal development, this cell type revealed no peroxidase activity and was identified with the terminal tubule cell of the newborn. The morphologic and cytochemical findings indicate that terminal tubule cells and proacinar cells are committed cells; the former differentiate toward 2nd order intercalated duct cells and the latter transform to mature acinar cells.

scholarly journals INDUCTION OF ENDOMETRIAL PEROXIDASE SYNTHESIS AND SECRETION BY ESTROGEN AND ESTROGEN ANTAGONIST

1974 ◽  
Vol 62 (2) ◽  
pp. 449-459 ◽  
Author(s):  
Andrew Churg ◽  
Winston A. Anderson
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Peroxidase Activity ◽  
Secretory Granules ◽  
Combined Treatment ◽  
Initial Injection ◽  
Immature Rats ◽  
Glandular Cells ◽  
Endogenous Peroxidase ◽  
Estrogen Antagonist

Synthesis of peroxidase was induced in the uterine epithelium of immature rats by multiple doses over a 24–96-h period of either 17 ß-estradiol, the estrogen-antagonist Parke-Davis CI-628, or a combination of estradiol plus antagonist. Endogenous peroxidase activity first appeared in the cisternae of the rough endoplasmic reticulum of surface epithelial and glandular cells within 24–48 after the initial injection. Uterine peroxidase activity was also visible in the cisternae of the Golgi apparatus, in Golgi-derived secretory granules, and within the uterine and glandular lumen. Some cells of the epithelium produced little or no peroxidase, even after 96 h. Whereas the antagonist appeared to induce synthesis and secretion of peroxidase, neither the antagonist alone nor the combined treatment (estradiol plus antagonist) reproduced the estradiol-mediated growth in organ size and increased lumen diameter.

scholarly journals Factors affecting the sensitivity and specificity of the cytochemical reaction for the anti-horseradish peroxidase antibody in lymph tissue sections.

1980 ◽  
Vol 28 (7) ◽  
pp. 645-652 ◽  
Author(s):  
W Straus
Keyword(s):  
Horseradish Peroxidase ◽  
Lymph Nodes ◽  
Sensitivity And Specificity ◽  
Peroxidase Activity ◽  
Additional Advantage ◽  
Tissue Sections ◽  
Endogenous Peroxidase ◽  
Cytochemical Reaction ◽  
Cold Acetone ◽  
Antibody Reaction

Factors which increase the sensitivity and specificity of the cytochemical reaction for the antibody to horseradish peroxidase (HRP) in precursors of plasma cells and in lymphocytes were studied in sections of popliteal lymph nodes of rats. The lymph nodes were removed 3-5 days after a secondary injection of HRP into the footpads and were fixed for 5 hr in a 4% cold formaldehyde solution (Straus W: Histochemistry 53:273, 1977). Brief postfixation of the frozen sections with cold acetone improved the retention of the antigen at the sites of the antibody in the precursor cells, and it improved the quality of fixation without appreciably weakening the antigen-binding capacity of the antibody. The cytochemical reaction for the anti-HRP antibody was intensified by staining with diaminobenzidine (DAB) and H2O2 at pH 5-6, or by staining at pH 7.4 in the presence of imidazole. Imidazole partially inhibited endogenous peroxidase activity. Pretreatment with phenylhydrazine prevented nonspecific background adsorption of HRP. Phenylhydrazine had the additional advantage of inhibiting most of the endogenous peroxidase activity (Straus W: J Histochem Cytochem 20:949, 1972). The intensity of the antibody reaction in the proplasma cells developing in the medullary cords varied greatly depending on the stage of maturation from lymphocytes and blast cells. Many lymphocytes in the cortex of the lymph node showed a strong perinuclear antibody reaction when the tissue sections were postfixed with cold acetone, and the peroxidase complexed to the antibody was visualized by staining with DAB and H2O2 at pH 5-6. The antibody reaction also occurred at the surgace of many lymphocytes when the tissue sections, postfixed with cold acetone, were stained with DAB and H2O2 at pH 7.4 in the presence of imidazole. Other lymphocytes showed a strong surface, perinuclear, and cytoplasmic antibody reaction after staining at pH 5-6 as well as after staining at pH 7.4, while yet other lymphocytes remained unstained.

scholarly journals Identification of a novel two-component system SenS/SenR modulating the production of the catalase-peroxidase CpeB and the haem-binding protein HbpS in Streptomyces reticuli

Microbiology ◽  
2005 ◽  
Vol 151 (11) ◽  
pp. 3603-3614 ◽  
Author(s):  
Darío Ortiz de Orué Lucana ◽  
Peijian Zou ◽  
Marc Nierhaus ◽  
Hildgund Schrempf
Keyword(s):  
Peroxidase Activity ◽  
Response Regulator ◽  
Binding Protein ◽  
Streptomyces Avermitilis ◽  
Binding Motif ◽  
Two Component System ◽  
Component System ◽  
Regulatory Cascade ◽  
Two Component

The Gram-positive soil bacterium and cellulose degrader Streptomyces reticuli synthesizes the mycelium-associated enzyme CpeB, which displays haem-dependent catalase and peroxidase activity, as well as haem-independent manganese-peroxidase activity. The expression of the furS–cpeB operon depends on the redox regulator FurS and the presence of the haem-binding protein HbpS. Upstream of hbpS, the neighbouring senS and senR genes were identified. SenS is a sensor histidine kinase with five predicted N-terminally located transmembrane domains. SenR is the corresponding response regulator with a C-terminal DNA-binding motif. Comparative transcriptional and biochemical studies with a designed S. reticuli senS/senR chromosomal disruption mutant and a set of constructed Streptomyces lividans transformants showed that the presence of the novel two-component system SenS/SenR negatively modulates the expression of the furS–cpeB operon and the hbpS gene. The presence of SenS/SenR enhances considerably the resistance of S. reticuli to haemin and the redox-cycling compound plumbagin, suggesting that this system could participate directly or indirectly in the sensing of redox changes. Epitope-tagged HbpS (obtained from an Escherichia coli transformant) as well as the native S. reticuli HbpS interact in vitro specifically with the purified SenS fusion protein. On the basis of these findings, together with data deduced from the S. reticuli hbpS mutant strain, HbpS is suggested to act as an accessory protein that communicates with the sensor protein to modulate the corresponding regulatory cascade. Interestingly, close and distant homologues, respectively, of the SenS/SenR system are encoded within the Streptomyces coelicolor A3(2) and Streptomyces avermitilis genomes, but not within other known bacterial genomes. Hence the SenS/SenR system appears to be confined to streptomycetes.

scholarly journals Some effects of vitamin E and selenium deprivation on tissue enzyme levels and indices of tissue peroxidation in rainbow trout (Salmo gairdneri)

1985 ◽  
Vol 53 (1) ◽  
pp. 149-157 ◽  
Author(s):  
J. G. Bell ◽  
C. B. Cowey ◽  
J. W. Adron ◽  
Aileen M. Shanks
Keyword(s):  
Rainbow Trout ◽  
Vitamin E ◽  
Peroxidase Activity ◽  
Cumene Hydroperoxide ◽  
Dietary Vitamin ◽  
Salmo Gairdneri ◽  
Deficient Diet ◽  
Exudative Diathesis ◽  
Malondialdehyde Formation

1. Duplicate groups of rainbow trout (Salrno gairdnert) (mean weight 11 g) were given for 40 weeks one of four partially purified diets that were either adequate or low in selenium or vitamin E or both.2. Weight gains of trout given the dually deficient diet were significantly lower than those of trout given a complete diet or a diet deficient in Se. No mortalities occurred and the only pathology seen was exudative diathesis in the dually deficient trout.3. There was significant interaction between the two nutrients both with respect to packed cell volume and to malondialdehyde formation in the in vitro NADPH-dependent microsomal lipid peroxidation system.4. Tissue levels of vitamin E and Se decreased to very low levels in trout given diets lacking these nutrients. For plasma there was a significant effect of dietary vitamin E on Se concentration.5. Glutathione (GSH) peroxidase (EC 1. 1 1. 1.9) activity in liver and plasma was significantly lower in trout receiving low dietary Se but was independent of vitamin E intake. The ratios of hepatic GSH peroxidase activity measured with cumene hydroperoxide and hydrogen peroxide were the same for all treatments. This confirms the absence of a Se-independent GSH peroxidase activity in trout liver.6. Se deficiency did not lead to any compensatory increase in hepatic GSH transferase (EC 2. 5. 1. 18) activity; values were essentially the same in all treatments.7. Plasma pyruvate kinase (EC 2. 7. 1.40) activity increased significantly in the trout deficient in both nutrients. This was thought to be due to leakage of the enzyme from the muscle and may be indicative of incipient (subclinical) muscle damage.

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