| heme-environment of horseradish peroxidase as observed by oxygen-17 superhyperfine interaction in epr. | | 1979 | 227384 |
| the discrete anatomical localization of vagal aortic afferents within a catecholamine-containing cell group in the nucleus solitarius. | the centripetal transport of horseradish peroxidase (hrp) was used to visualize the central projections of afferent fibers of the aortic arch nerve to the nucleus solitarius in pigeons. our results indicate that aortic nerve afferents have a restricted distribution within one subdivision of the nucleus solitarius, designated the subnucleus sulcalis dorsalis. histofluorescence studies revealed that the aortic nerve projection area is extremely rich in catecholamine-containing neurons. | 1979 | 466439 |
| thalamic afferents to the visual cortex in congenitally anophthalmic mice. | retrograde cell labelling with horseradish peroxidase (hrp) has been used to study the thalamic afferents to the primary visual cortex (area 17) in mutant h1-zrdct-an ('eyeless') mice, in which the eyes are missing throughout development. injections of hrp that were localised to a subregion of area 17, resulted in the labelling of a group of neurons in the ipsilateral dorsal lateral geniculate nucleus, showing the existence of a point-to-point connectivity. many labelled cells were also found in ... | 1979 | 530479 |
| ultrastructure of the synapses of sensory neurons that mediate the gill-withdrawal reflex in aplysia. | we have identified the processes of mechanoreceptor sensory neurons by intracellular injection of horseradish peroxidase in order to study the structure of synapses which exhibit profound, behaviourally-relevant plasticity. these synapses are located at small, varicose expansions along or at the end of the fine, microtubule-containing neurites, and they are crowded with vesicles some of which are associated with the varicosity membrane at regions of membrane specialization morphologically equiva ... | 1979 | 490189 |
| the use of lectins and cholera toxin for the detection of surface carbohydrates of cultured neurons and neuroblastoma. | conjugates of horseradish peroxidase with the lectins ricin (d-galactose), wheat germ agglutinin (n-acetylglucosamine), phytohemagglutinin (n-acetylgalactosamine), and with cholera toxin (gm1 ganglioside) were used for a cytochemical detection of corresponding termin al carbohydrates, or glycolipids on cell surfaces of cultured neurons and neuroblastoma cells. cells were labeled at 4 degrees c with the above ligands and their adsorptive endocytosis was studied after incubations at 37 degrees c i ... | 1979 | 479560 |
| acetylcholine receptors in regenerating muscle accumulate at original synaptic sites in the absence of the nerve. | we examined the role of nerve terminals in organizing acetylcholine receptors on regenerating skeletal-muscle fibers. when muscle fibers are damaged, they degenerate and are phagocytized, but their basal lamina sheaths survive. new myofibers form within the original basal lamina sheaths, and they become innervated precisely at the original synaptic sites on the sheaths. after denervating and damaging muscle, we allowed myofibers to regenerate but deliberately prevented reinnervation. the distrib ... | 1979 | 479308 |
| horseradish peroxidase. xxxiv. oxidation of compound ii to i by periodate and inorganic anion radicals. | the one-electron oxidation of horseradish peroxidase compound ii to compound i by sodium periodate was observed. the bimolecular rate constant for the naio4--compound ii interaction is equal to 9.5 +/- 1 x 10(-3) m-1s-1 at room temperature. irradiation, using ultraviolet light, of the solution containing compound ii and persulfate in the presence of bicarbonate, chloride, or bromide, leads ot the fast accumulation of compound i due to the oxidative action of so4, co3, cl2, and br2 anion radicals ... | 1979 | 232001 |
| layer i of striate cortex of tupaia glis and galago senegalensis: projections from thalamus and claustrum revealed by retrograde transport of horseradish peroxidase. | we have examined the origin of the subcortical projections to the superficial layers of the striate cortex in tupaia glis and galago senegalensis by using the retrograde transport of hrp. crystals of hrp were laid directly on the moist pial surface of the cortex which had been gently pricked with a small glass pipette. the diffusion of hrp was limited to layers i and ii by restricting the length of time that the hrp was in contact with the surface. following the application of hrp to the striate ... | 1979 | 110851 |
| horseradish peroxidase. xxxvi. on the difference between peroxidase and metmyoglobin. | | 1979 | 486194 |
| the oxidation and decarboxylation of retinoic acid by horseradish peroxidase. | the decarboxylation of retinoic acid by horseradish peroxidase was investigated. a marked increase in the yield of products was obtained. however, the data indicated the reaction was a nonenzymatic, heme catalyzed peroxidation. previously reported requirements for phosphate, oxygen and ferrous ion were eliminated when hydrogen peroxide was provided. peroxide also eliminated the edta and cyanide induced inhibition of the phosphate dependent system. in the presence of hydrogen peroxide, horseradis ... | 1979 | 476130 |
| the effect of hyperglycemia on brain capillary permeability in the lizard, anolis carolinensis. a freeze-fracture analysis of blood-brain barrier pathology. | the anatomical basis of the blood-brain barrier in the american chameleon, anolis carolinensis, is the system of tight intercellular junctions that occurs between apposed endothelial cells of brain capillaries. under normal physiological conditions, capillaries in the brain cortex of these animals remain sealed by interendothelial zonulae occludentes and, consequently, escape of exogenous tracer proteins such as horseradish peroxidase (hrp) into the extracellular compartment of the central nervo ... | 1979 | 466426 |
| new ultrastructural evidence for a protein transport system in endothelial cells of gerbil brains. | pathways for transfer of horseradish peroxidase (hrp) across the cerebral microvasculature were studied in mongolian gerbils after inducing either unilateral carotid-artery ligation or intracarotid air embolism. electron microscopy on samples from both ipsilateral and contralateral brain hemispheres showed the reaction product (hrp) in the endothelial cytoplasm of capillaries and arteriols in all animals; in the basal lamina, hrp was seen only after long (3--4 h) ischemic periods. hrp was seen w ... | 1979 | 474070 |
| electron paramagnetic resonance analyses of horseradish peroxidase in situ and after purification. | | 1979 | 37888 |
| localization of acetylcholine receptors by means of horseradish peroxidase-alpha-bungarotoxin during formation and development of the neuromuscular junction in the chick embryo. | the localization of acetylcholine receptors (achr) in the surface of developing myogenic cells of the chick embryo anterior and posterior latissimus dorsi muscles in relation to the process of innervation has been studied at the ultrastructural level utilizing a horseradish peroxidase-alpha-bungarotoxin conjugate. localized concentrations of achr were found in small regions 0.1-0.4 micron in width on the surface of myogenic cells of 10- to 14-d-old muscles. surface specializations consisting of ... | 1979 | 479297 |
| [visual projections in to the brain of the sturgeon acipenser güldenstädti]. | visual projections have been studied after unilateral lesion of the optic nerve. degenerated fibers and terminals, as well as fibers labelled by horseradish peroxidase were found contralaterally in the lateral geniculate thalamic nucleus, the second (stratum opticum) and the third (stratum fibrosum et griseum superficiale) layers of the midbrain tectum. in other brain structures (lateral ventrothalamic nucleus, in the pretectal area--cortical nucleus, pretectal nucleus, posterior comissure nucle ... | 2007 | 473992 |
| quantitative studies of retinal ganglion cells in a turtle, pseudemys scripta elegans. i. number and distribution of ganglion cells. | multiple pathways for the transmission of visual information from retina to brain have been described in reptiles, but little is known about their functional organization. these parallel channels begin at the retina, and we have therefore begun to study the functional organization of retinal ganglion cells in the turtle, pseudemys scripta elegans. this paper describes the numbers and distribution of cells in the ganglion cell layer. to develop criteria for the identification of ganglion cells, w ... | 1979 | 457929 |
| intracellular localization of markers within injected or cut frog muscle fibers. | many experimental procedures require drastic alterations of muscle fibers, such as cutting the fiber or injecting molecular probes through microelectrodes. we report the ultrastructure of similarly altered muscle fibers and the intracellular distribution of injected horseradish peroxidase (hrp). cut fibers appear structurally normal at distances greater than 500 microm from the cut end, however, the structure deteriorates nearer to the cut. hrp diffuses longitudinally about 2,000 micrometer from ... | 1979 | 313713 |
| localization of horseradish peroxidase-alpha-bungarotoxin binding in crustacean axonal membrane vesicles and intact axons. | a conjugate of alpha-bungarotoxin with horseradish peroxidase was used to visualize alpha-bungarotoxin binding sites at the fine structural level in isolated axonal membrane vesicles from lobster walking leg nerve. these plasma membrane vesicles have previously been shown to exhibit saturable binding of [3h]nicotine and [3h]acetylcholine. binding of the toxin was identified in the axon plasma membrane and could be blocked by pretreatment with excess free alpha-bungaratoxin or d-tubocurarine. bin ... | 1979 | 291022 |
| horseradish peroxidase compound i: evidence for spin coupling between the heme iron and a 'free' radical. | | 1979 | 223878 |
| effects of isoproterenol on the dense core and perigranular membrane of atrial specific granules. | following subcutaneous injections of isoproterenol hydrochloride (iso), atrial cells present a large number of partly degranulated or completely clear "specific granules" enclosed by an intact membrane. such profiles were never encountered in normal controls and might suggest iso-induced release of a secretory product. permeability of perigranular membrane was tested using the extracellular macromolecular tracer horseradish peroxidase (hrp). reaction product was entirely absent within granules o ... | 1979 | 383301 |
| thalamic projections from the lateral reticular nucleus in the opossum as determined by horseradish peroxidase histochemistry. | | 1979 | 435983 |
| midbrain projections to the trigeminal, facial and hypoglossal nuclei in the opossum. a study using axonal transport techniques. | it has been proposed (see berntson and micco for review) that circuits intrinsic to the midbrain play an important role in the elaboration and control of behaviors involving the motor nuclei of the trigeminal, facial and hypoglossal nerves (e.g. defense, threat, attack); but because of technical problems, it has been difficult to analyze their organization. using the horseradish peroxidase technique we have localized those midbrain neurons which project to each of the above nuclei and by using t ... | 1979 | 86379 |
| endocytosis of cholera toxin in gerl-like structures of murine neuroblastoma cells pretreated with gm1 ganglioside. cholera toxin internalization into neuroblastoma gerl. | cholera toxin (ct), covalently attached to horseradish peroxidase (hrp), is a specific cytochemical marker for gm1 ganglioside (gm1) and retains the ability of the native toxin to raise levels of cyclic amp in avian erythrocytes. using a cytochemical stain for hrp, we found that 9% of control cultured murine neuroblastoma cells bound cholera toxin-horseradish peroxidase conjugates (ct-hrp) on their surfaces after incubations for 1 h at 4 degrees c. exogenous gm1, the natural receptor of ct, beco ... | 1979 | 457774 |
| studies on the conjugation of horseradish peroxidase to immunoglobulin g via glutaraldehyde. | horseradish peroxidase was conjugated to immunoglobulin g via glutaraldehyde by a two-step procedure using an increasing excess of peroxidase in the second step reaction. the yield of conjugated monomeric igg and the amount of free igg were analyzed by sds-polyacrylamide electrophoresis and gel-filtration. the antigen binding capacity of the enzyme-antibody conjugates was evaluated by radial immunodiffusion. conjugation of peroxidase to igg with a 1:20 molar:molar excess of glutaraldehyde-activa ... | 1979 | 116093 |
| chemical and enzymatic intermediates in the peroxidation of o-dianisidine by horseradish peroxidase. 1. spectral properties of the products of dianisidine oxidation. | | 1979 | 221005 |
| resonance raman investigations of chloroperoxidase, horseradish peroxidase, and cytochrome c using soret band laser excitation. | resonance raman spectra of the heme protein chloroperoxidase in its native and reduced forms and complexed with various small ions are obtained by using laser excitation in the soret region (350-450 nm). additionally, raman spectra of horseradish peroxidase, cytochrome p-450cam, and cytochrome c, taken with soret excitation, are presented and discussed. the data support previous findings that indicate a strong analogy between the active site environments of chloroperoxidase and cytochrome p-450c ... | 1979 | 36129 |
| mechanism of the chlorination reaction catalyzed by horseradish peroxidase with chlorite. | | 1979 | 429342 |
| oxidation of horseradish peroxidase compound ii to compound i. | in the reaction between equimolar amounts of horseradish peroxidase and chlorite, the native enzyme is oxidized directly to compound ii (hewson, w.d., and hager, l.p. (1979) j. biol. chem. 254, 3175-3181). at acidic ph but not at alkaline values, this initial reaction is followed by oxidation of compound ii to compound i. the highly ph-dependent chemistry of compound ii can be readily demonstrated by the reduction of compound i, with ferrocyanide at acidic, neutral, and alkaline ph values. titra ... | 1979 | 34616 |
| studies on horseradish peroxidase in dimethyl sulphoxide/water mixtures. the activation of hydrogen peroxide and the binding of fluoride. | we studied the variation in spectra and in reactivity towards h2o2 of solutions of horseradish peroxidase in dimethyl sulphoxide/water mixtures, obtained by diluting stock solutions of the enzyme in either water or dimethyl sulphoxide, and assayed the enzyme activity and studied the binding of f- by the peroxidase in 65% (v/v) dimethyl sulphoxide. a broadly similar pattern of changes is observed whether one starts from water or from dimethyl sulphoxide; the changes are essentially reversible, th ... | 1979 | 486079 |
| effects of colchicine on endocytosis and cellular inactivation of horseradish peroxidase in cultured chondrocytes. | horseradish peroxidase (hrp) was used as a marker to study the effects of microtubule-disruptive drugs on uptake and cellular inactivation of exogenous material in cultures of embryonic chick chondrocytes. hrp was ingested by fluid endocytosis, and intracellular enzyme activity subsequently diminished exponentially with time. cytochemically, reaction product for hrp was found in vesicles often located close to the dictyosomes of the golgi complex. colchicine and vinblastine caused disappearance ... | 1979 | 468912 |
| enzyme immunoassay of estrogen-like substances in plasma, with polyethylene glycol as precipitant. | we devised an enzyme immunoassay for plasma estrogen-like substances in pregnancy, using estriol covalently linked to horseradish peroxidase. free and bound steroid were separated by use of polyethylene glycol reagent. the assay satisfies the normal criteria of specificity and precision. results obtained by radioimmunoassay and enzyme immunoassay agreed well. our assay is particularly applicable in smaller clinical laboratories to routine determination of plasma estriol in pregnancy. | 1979 | 373925 |
| some telencephalic connections in the frog, rana pipiens. | some afferent, efferent and intrinsic connections of the telencephalon of rana pipiens were studied using a horseradish peroxidase method. afferents to the telencephalon from thalamic and brain stem cell groups were demonstrated. these findings, taken together with the results of previous studies, indicate that separate thalamic cell groups project visual, auditory and somatosensory information onto the striatum. a separate thalamic cell group projects to the medial telencephalic wall and probab ... | 1979 | 311788 |
| impermeability of hagfish cerebral capillaries to horseradish peroxidase. an ultrastructural study. | brain capillaires and their permeability to intravenously injected horseradish peroxidase, hrp, (mw: 40,000) were examined electron-microscopically in an attempt to find a structural explanation for the poorly developed blood-brain barrier in the hagfish, myxine glutinosa. in particular, it was the aim of this study to examine the role of the numerous endothelial vesicles and tubules in the transport of this tracer between blood and brain. many of the vesicles and tubules were found to be in con ... | 1979 | 476792 |
| ultrastructure of photoreceptors in the eye of hermissenda labelled with intracellular injections of horseradish peroxidase. | the terminal processes of single and of pairs of identified photoreceptors in the eyes of the nudibranch mollusc hermissenda crassicornis were studied by light and transmission electron microscopy after their somata were labelled by intracellular iontophoresis of horseradish peroxidase (hrp). the hrp spread from the somata into the axons and fine terminal processes within the neuropil of the cerebropleural ganglia. the photoreceptors ended in extensive secondary branches in the neuropil where pr ... | 1979 | 469572 |
| [purification of commercial horseradish peroxidase for the use in enzyme immunoassay]. | | 1979 | 384697 |
| alpha-bungarotoxin-horseradish peroxidase conjugate: preparation, properties and utilization for the histochemical detection of acetylcholine receptors. | a method is presented for the efficient conjugation of horseradish peroxidase to alpha-bungarotoxin. the 1:1 molar conjugate obtained is purified to completion by gel filtration on sephadex g-100, followed by ion exchange chromatography on cm-sephadex. the conjugate retains half of the activity of unmodified horseradish peroxidase and binds effectively to the nicotinic acetylcholine receptor of muscle. the conjugate is proven to be useful reagent for the histochemical staining of the receptor on ... | 1979 | 376692 |
| on the course and origin of cranial nerves in the teleost fish gnathonemus determined by ortho- and retrograde horseradish peroxidase axonal transport. | by horseradish peroxidase (hrp) labelling the course and origin of the ii-x cranial nerves are identified in the teleost fish gnathonemus petersii. roots as well as motor and sensory nuclei in the viscero- and somatomotor and somatosensory areas are localised. earlier data of comparative and experimental anatomical observations are completed, partly confirmed or corrected. | 1979 | 514539 |
| localization of rhodopsin in isolated, osmotically intact rod outer segment discs. | localization of rhodopsin and its position in the membrane has been the subject of numerous studies. most recently, immunocytochemical techniques have been employed to localize the opsin component of the molecule in in situ rod outer segments. due to the problems inherent in localization procedures (penetration and mechanical interference) we have utilized isolated, osmotically intact rod outer segment discs in this study. specific antibodies to chromatographically pure rhodopsin were prepared a ... | 1979 | 314460 |
| proprioceptive reflex connections of head musculature and the mesencephalic trigeminal nucleus in the carp. | the location of the sensory cells concerned with the proprioception of respiratory and extraocular musculature in the carp was studied by retrograde transport of horseradish peroxidase. sensory cell labeling after intramuscular hrp injection was exclusively found in the trigeminal-facial-anterior lateral line ganglion complex. the muscles innervated by the trigeminal system are represented in the more rostral ganglion areas, the muscles innervated by the facial system in the more caudal ganglion ... | 1979 | 762276 |
| the mechanism of indole-3-acetic acid oxidation by horseradish peroxidases. | the oxygen-consuming oxidation of indole-3-acetic acid (iaa) occurred much faster in the presence of horseradish peroxidase c (neutral isoenzyme) than in the presence of horseradish peroxidase a (acidic isoenzyme). an intermediate oxidation product of iaa was found to be a hydroperoxide species that reacted with the ferric enzymes to form compound i at second order rate constants of 6.8 x 10(3) m-1--s-1 for peroxidase a and 2.0 x 10(6) m-1--s-1 for peroxidase c at ph 4.4 the hydroperoxide concen ... | 1979 | 762098 |
| thalamic projections to layer i of striate cortex shown by retrograde transport of horseradish peroxidase. | the diffusion of horseradish peroxidase was restricted to layers i and ii of the striate cortex in tupaia glis and galago senegalensis. in the lateral geniculate body of tupaia labeled cells were found only in layer 3; some labeled cells were also found in the lateral nucleus. in galago labeled cells were found only in layers 4 and 5 of the lateral geniculate body; a band of cells was also found in the pulvinar nucleus. these results support the distinction between two overlapping thalamic syste ... | 1979 | 760205 |
| horseradish peroxidase labeled antisera--a diagnostic method for evaluating the percentages of b lymphocytes in peripheral blood. | horseradish peroxidase labeled antisera supplied commercially was used to evaluate b lymphocytes in peripheral blood. this technique not only gave comparable results to the conventional fluorescein method, but also proved to be more advantageous. | 1979 | 376687 |
| afferent and efferent components of the facial nerve in the bullfrog (rana catesbeiana). | the afferent and efferent components of the facial nerve were traced within the brain stem of rana catesbeiana, using three different neuroanatomical techniques. primary afferent fibers could be traced to the spinal tract of trigeminal nerve and to fasciculus solitarius as far caudally as the first or second spinal segment, using silver degeneration methods. cobalt filling of of the entire nerve showed the same distribution of afferent fibers, as well as the filling of the cells within the mesen ... | 1979 | 310889 |
| efferent connections from the brain to the frontal organ in rana temporaria demonstrated by labeling with horseradish peroxidase. | after injection of horseradish peroxidase into the frontal organ of rana temporaria, labeled perikarya were found in the medial part of the amygdala, the preoptic area, the nucleus rotundus, the pretectal area, and the lateral parts of the midbrain central griseum. | 1979 | 311252 |
| the organization of the electromotor nucleus and extraocular motor nuclei in the stargazer (astroscopus y-graecum). | the organization of the oculomotor and electromotor systems was examined in the stargazer, a teleost. the electromotor system in these animals is a derivative of the oculomotor system. the extraocular motor nuclei and nerves consist of approximately equal numbers of motoneurons and axons (about 100 per muscle). in contrast, electromotor axons appear to branch several times within the intracranial portion of the iiird nerve. the topographical organization of the motoneurons was examined using ret ... | 1979 | 762265 |
| the role of protein and porphyrin in the reactivity of horseradish peroxidase toward hydrogen donors. | | 1979 | 435299 |
| tomato peroxidase: purification, characterization, and catalytic properties. | a major peroxidase has been found in the tomato pericarp (lycopersicon esculentum var. tropic) of the ripe and green fruit. a purification scheme yielding this enzyme approximately 85% pure has been developed. the tomato enzyme resembles horseradish peroxidase (hrp) in a standard peroxidase assay and in its ability to be reduced to ferroperoxidase, to be converted to oxyferroperoxidase (compound iii), and to form peroxidase complexes with hydrogen peroxide (compounds i and ii). in contrast to th ... | 1979 | 16660701 |
| regeneration of cerebral microvessels: a morphologic and histochemical study after local freeze-injury. | the sequential changes that occur during regeneration of cerebral microvessels was studied in young mice after a local freeze-injury. the immediate breakdown in the blood-brain barrier to horseradish peroxidase was followed by dissolution of cells in the vessel wall although the basal lamina was preserved. this residual basal lamina formed the pathway for the orderly regeneration of microvessels. three days after injury, reactive endothelial cells with prominent pinocytosis and patent interendot ... | 1979 | 762954 |
| an ultrastructural study of the neurosecretory canopy cell of the pond snail lymnaea stagnalis (l.), with the use of the horseradish peroxidase tracer technique. | the paired, electrotonically coupled neurosecretory canopy cells (cc) of the pond snail lymnaea stagnalis were microiontophoretically injected with horseradish peroxidase (hrp). whole mount preparations and ultrathin sections of injected cc were studied to describe in detail the morphology of the cc, their axon tracts and neurohaemal areas. the cc release their secretory product at three different sites, viz. from the soma and from axon terminals in the intercerebral commissure and in the median ... | 1979 | 527029 |
| regional functional differentiation in the gut of the grasscarp, ctenopharyngodon idella (val.). | a regional differentiation--reflecting structural differences--of the intestine of larval and juvenile grasscarps can be illustrated by studying the activity of alkaline phosphatase and the uptake of orally administered horseradish peroxidase. pinocytosis takes place in a welldefined area of about 23% of the length of the gut (segment ii). neither the rostral +/- 68% (segment i) nor the caudal +/- 9% (segment iii) shows absorption of the enzyme. alkaline phosphatase activity, mainly localized at ... | 1979 | 521316 |
| occluding-like junctions at mesaxons of central myelin in anolis carolinensis are not 'tight'. a freeze-fracture-protein tracer analysis. | the junctional complexes of the myelin sheath of central nervous system axons in the american chameleon, anolis carolinensis, exhibit an intramembrane ridge and groove construction in freeze-fracture replicas that has usually been interpreted in other organisms as evidence for an occluding or tight intercellular junction. close examination of pf fracture face ridges, however, shows them to be made up of discontinuous rows of particles of variable length separated by frequent gaps of non-uniform ... | 1979 | 473168 |
| an evaluation of the immunoperoxidase technique in renal biopsy diagnosis. | an evaluation of the use of horseradish peroxidase labelled antisera against igg, igm, iga and c3 compared with corresponding antisera labelled with fluorescein isothiocyanate has been carried out on renal biopsy material from 200 patients with renal disease. a disparity between the two methods was observed in 10-19% of the readings according to the antigen being demonstrated. the majority of differences recorded would not have influenced the executive diagnosis. where the immunological results ... | 1979 | 371888 |
| in vitro induced pinocytotic activity by a juvenile hormone analogue in oocytes of drosophila melanogaster. | pinocytotic activity has been analyzed in drosophila oocytes following either in vivo or in vitro exposure to horseradish peroxidase. the enzyme tracer gains access to the yolk spheres only when supplied to the oocyte in vivo. in oocytes cultured in vitro, peroxidase remains restricted to the residual coated vesicles and to the tubular profiles formed in excess in the cortical ooplasm. in an attempt to induce peroxidase uptake by oocytes cultured in vitro, various incubations were tested. among ... | 1979 | 117896 |
| [horseradish peroxidase: a study of the kinetics and the determination of optimal reaction conditions, using hydrogen peroxide and 2,2'-azinobis 3-ethylbenzthiazoline-6-sulfonic acid (abts) as substrates (author's transl)]. | the reaction of the two substrates hydrogen peroxide and abts with horseradish peroxidase was studied kinetically. enzyme activity was determined as a function of substrate concentration and ph. michaelis constants were determined for the two substrates at various ph values. it was found that the affinity of the enzyme for abts decreases with increasing ph, and that with higher abts concentrations the ph optima of the reaction are shifted towards neutrality. maximal rate is reached at ph 4.2 wit ... | 1979 | 33227 |
| development of the blood-brain barrier to horseradish peroxidase in the chick embryo. | one to 20 mg of horseradish peroxidase (hrp) was injected into the allantoic vein of chick embryos between the 7th to 21st day of incubation and its penetration from blood into the interstitium of cerebellum and spinal cord (upper thoracic) was examined by light and electron microscopy in order to study development of the blood-brain barrier. until the 12th day of incubation (stage 38) the reaction products, indicating the presence of peroxidase, were distributed in every region of the intercell ... | 1978 | 737715 |
| cell lineage analysis by intracellular injection of a tracer enzyme. | cell lineages during development of leeches can be ascertained by injection of horseradish peroxidase as a tracer into identified cells at early stages of embryogenesis. the injected embryos continue their normal development, in the course of which horseradish peroxidase is passed on in catalytically active form to the descendants of the injected cell. the distribution of the tracer enzyme and hence of the progeny of the injected cell can then be observed at a later stage of development by stain ... | 1978 | 725606 |
| membrane recycling in the cone cell endings of the turtle retina. | the ultrastructural effects of dark, light, and low temperature were investigated in the cone cell endings of the red-eared turtle (pseudemys scripta elegans). thin sections revealed that in dark-adapted retinas maintained at 22 degrees c, the neural processes which contact the cone cells at the invaginating synapses penetrated deeply into the photoreceptor endings. when dark-adapted retinas were illuminated for 1 h at 22 degrees c, the invaginating processes were apparently extruded from the sy ... | 1978 | 730768 |
| termination of electroreceptor and mechanical lateral line afferents in the mormyrid acousticolateral area. | the projection regions of electroreceptor and mechanical lateral line afferents in electric fish of the mormyridae family are described. electroreceptor afferents from the posterior dorsal skin run in the dorsal branch of the posterior lateral line nerve. electroreceptor afferents from ventral skin and mechanical lateral line afferents and efferents run in the ventral branch of the nerve. horseradish peroxidase (hrp) injections into each branch resulted in filling of its central terminals with t ... | 1978 | 721966 |
| contacts between receptors and electrophysiologically identified neurones in the retina of the larval tiger salamander. | 1. following the intracellular recording of bipolar and horizontal cell responses, each unit was injected with horseradish peroxidase and a histochemical staining used to identify it at the level of the light and electron microscopes.2. centre-depolarizing bipolar cells made contact with rods and cones at basal and ribbon junctions, the latter being fewer. centre-hyperpolarizing bipolar cells made the same types of contacts with the receptors, but ribbon junctions predominated.3. it appears, the ... | 1978 | 217992 |
| the use of rhodamin b for the identification of injected horseradish peroxidase in the brain. | horseradish peroxidase injected into the brain of the marmoset, callithrix jacchus, is demonstrated by fluorescence microscopy following histochemical reaction with homovanillic acid and rhodamin b. usefulness and efficiency of the method are discussed in comparison with other procedures for the demonstration of hrp. | 1978 | 103870 |
| horseradish peroxidase. xxxii. ph dependence of the oxidation of l-(-)-tyrosine by compound i. | the rate of oxidation of l-(-)-tyrosine by horseradish peroxidase compound 1 has been studied as a function of ph at 25 degrees c and ionic strength 0.11. over the ph range of 3.20--11.23 major effects of three ionizations were observed. the pka values of the phenolic (pka = 10.10) and amino (pka = 9.21) dissociations of tyrosine and a single enzyme ionization (pka = 5.42) were determined from nonlinear least squares analysis of the log rate versus ph profile. it was noted that the less acidic f ... | 1978 | 35272 |
| origin of the retina from both sides of the embryonic brain: a contribution to the problem of crossing at the optic chiasma. | cells originating from one of the first two blastomeres of the frog embryo were labeled either by injecting them with horseradish peroxidase or by changing the ploidy of one blastomere. both methods show the labeled cells confined to the same side of the brain as the labeled blastomere except for cells that have moved from the opposite side into the ventral diencephalon and ventral part of the retina. reciprocal movement of cells from each side of the prospective forebrain into the prospective r ... | 1978 | 705349 |
| the hypothalamic neurosecretory systems of the japanese quail as revealed by retrograde transport of horseradish peroxidase. | within 24-48 h after injection of horseradish peroxidase (hrp) into the neural lobe or into the median eminence of adult japanese quail dense accumulations of its reaction product (hrp-rp) can be demonstrated in axons of the hypothalamo-hypophysial tract and in the magnocellular neurosecretory perikarya of the supraoptic and paraventricular nuclei as well as in scattered neurons of the accessory hypothalamic neurosecretory nuclei. the hrp-rp-containing nerve fibers, which are beaded in appearanc ... | 1978 | 82485 |
| horseradish peroxidase tracing of visceral efferent and primary afferent pathways in the cat's sacral spinal cord using benzidine processing. | sacral afferent and preganglionic efferent neurons were labelled by applying horseradish peroxidase (hrp) to the central end of the transected pelvic nerve. preganglionic cells were evident as a narrow band of cells extending from the intermediolateral region dorsomedially beneath the dorsal horn. their dendrites were located primarily within the nucleus but also projected into the dorsolateral funiculus, along the lateral edge of the dorsal horn and to dorsal commissure. labelled primary affere ... | 1978 | 19605264 |
| peripheral innervation by migrating neuroblasts in the chick embryo. | horseradish peroxidase (hrp) was injected into the mandibular process of the first visceral arch in chick embryos of 3-6 days of incubation. on days 3 1 2 , 4 and 4 1 2 of incubation, this procedure resulted in granular reaction product in neuroblasts of the lateral trigeminal nucleus and in soma and processes of neuroblasts in the process of migrating from the medial column to form the lateral nucleus. on days 5 and 6 of incubation, similar labeling was found in cells migrating from the lateral ... | 1978 | 19605256 |
| simultaneous separation of acidic and basic isoperoxidases in wounded potato tissue by acrylamide gel electrophoresis. | preparation and use of a newly developed ph 4.3 horizontal thin layer acrylamide gel which permits the simultaneous separation of acidic and basic isoperoxidases in up to 30 samples is described. use of cytochrome c, horseradish peroxidase, and a purified potato isoperoxidase as internal standards for a range in isoelectric points of peroxidases from ph 3 to 11 is introduced to facilitate comparison of results obtained with different materials and different methods. distribution of tissue-specif ... | 1978 | 16660608 |
| the development of motor projection patterns in the chick hind limb. | 1. retrograde transport of horseradish peroxidase was used to map the initial projection patterns of lumbosacral motoneurones to the embryonic chick hind limb. 2. the stage 28 segmental projection pattern to each of the four primary muscle masses was characteristic and indistinguishable from the stage 36 projection pattern to the sum of the muscles derived from that mass. in addition, the adductor motoneurone pool was found to be similar in position (both rostro-caudal and mediolateral) at stage ... | 1978 | 731552 |
| development of functional motor innervation in supernumerary hindlimbs of the chick embryo. | 1. the development of functional motor innervation in supernumerary chick hindlimbs transplated to host embryos at stages 16--18, was studied throughout the embryonic period from stage 27 when peripheral synapses were first formed. 2. the innervation pattern, defined as the number and sequential order of spinal nerves innervating individual muscles, were determined for supernumerary hindlimbs innervated by thoracic, lumbosacral-thoracic, or wholly lumbosacral spinal cord segments. spinal nerves ... | 1978 | 731285 |
| oxidation of 2-nitropropane by horseradish peroxidase. involvement of hydrogen peroxide and of superoxide in the reaction mechanism. | incubation of aqueous solutions of 2-nitropropane in air causes a slow oxidation reaction that generates h(2)o(2). purified horseradish peroxidase catalyses the oxidation of such preincubated 2-nitropropane solutions according to the equation: [formula: see text] the ph optimum is 4.5 and k(m) for 2-nitropropane is 16mm. other nitroalkanes or nitro-aromatics tested are not oxidized at significant rates by peroxidase. h(2)o(2) or 2,4-dichlorophenol increases the rate of 2-nitropropane oxidation b ... | 1978 | 217346 |
| uptake and retrograde axonal transport of horseradish peroxidase in botulinum-intoxicated mice. | | 1978 | 80253 |
| avian efferent vestibular neurons identified by axonal transport of [3h]adenosine and horseradish peroxidase. | | 1978 | 80252 |
| extravascular transfer within the anuran pars intermedia. | to study the transport of protein from the blood into and throughout the sparsely vascularized pars intermedia of anurans, the electrondense tracer, horseradish peroxidase (hrp) was injected into the vascular system of adult frogs. a strong reaction product was localized in small vesicles in the cytoplasm of that portion of the stellate cells immediately beneath the vascular spaces. also, within two minutes after an injection of hrp, which was given during a period of one minute, the reaction pr ... | 1978 | 309794 |
| retrograde transport of horseradish peroxidase from the preoptic-anterior hypothalamic region to retinal ganglion cells in quail. | horseradish peroxidase was injected in the preoptic-anterior hypothalamic area of intact male quail and reacted with 3,3'-diaminobenzidine and hydrogen peroxide in eye sections. cells labelled with peroxidase reaction product were found in the ganglion layer of the retina. one possible function of such retinal-hypothalamic connections might be to participate in the photosexual reflex. | 1978 | 19605234 |
| cells of origin of propriospinal and ascending supraspinal fibers in a lizard (lacerta galloti). | the location of cells of origin of propriospinal and ascending supraspinal fibers has been determined by injecting horseradish peroxidase (hrp) unilaterally into various parts of the spinal cord of the lizard lacerta galloti. the distribution of retrogradely labeled cells after unilateral high spinal cord injections suggests that ascending supraspinal fibers are derived from neurons in the following areas: in the cervical intumescence in most areas of the spinal gray, particularly ipsilaterally, ... | 1978 | 19605233 |
| neuronal cell cultures as toxicologic test systems. | neuronal cell cultures now represent well-characterized systems with which acute and chronic toxicologic effects of a variety of agents can be evaluated. extensive synapse formation occurs over a period of days and weeks in these cell cultures and can be assayed semiquantitatively by morphological and electrophysiological means. detailed morphophysiologic correlations can be made using a technique for injecting an intracellular marker protein, horseradish peroxidase. a variety of neurochemical i ... | 1978 | 720311 |
| hardening of the sea urchin fertilization envelope by peroxidase-catalyzed phenolic coupling of tyrosines. | within minutes after its elevation from the egg surface, the sea urchin fertilization envelope (fe) becomes "hardened" by a reaction that renders it resistant to agents that solubilize, denature or degrade most proteins. peroxidase activity is released into the surrounding seawater from stronglyocentrotus purpuratus eggs during fertilization. evidence from several sources indicate that the catalytic action of the peroxidase is responsible for hardening the fe through the phenolic coupling of tyr ... | 1978 | 569021 |
| a sensitive manual enzyme immunoassay for thyroxine. | we describe an immunoassay for thyroxine in serum. in the assay specific antibody covalently bonded to latex particles is used, along with horseradish peroxidase as the label, and o-phenylenediamine as the chromogen. the flexible protocol is designed for manual execution. performance is similar to that of the highest-sensitivity thyroxine radioimmunoassays. results correlate well with radioimmunoassay (r = 0.99, slope = 0.93, y-intercept = 2.4 microgram/liter for 201 samples) and an automated en ... | 1978 | 359195 |
| [structure and function of horseradish peroxidase]. | | 1978 | 31196 |
| structural correlates of recurrent collateral interneurons producing both electrical and chemical inhibitions of the mauthner cell. | intracellular injections of horseradish peroxidase provided a basis for morphological identification of inhibitory interneurons belonging to the recurrent collateral network of the mauthner cell. their axons dilate to form unusually large bulbs surrounding the axon cap. the morphological appearance of these bulbs as well as intracellular recordings at their level indicate that they behave as nodes and serve as a final source of current for electrical inhibition of the mauthner cell. the axon of ... | 1978 | 30093 |
| observations on the development of brainstem-spinal systems in the north american oppossum. | the north american oppossum is born 12 to 13 days after conception and and is available for 90 days or more in an external pouch where it can be observed and experimentally manipulated. it is of particular interest that the hindlimbs of the newborn opossum are very immature and remain immobile for a week or more after birth. degeneration techniques reveal that immature brainstem axons are present within the marginal zone of the lumbosacral cord before hindlimb movements begin (our state i) and m ... | 1978 | 690268 |
| displaced ganglion cells in carp retina revealed by the horseradish peroxidase technique. | displaced ganglion cells were identified in the carp retina by the retrograde axonal transport of horseradish peroxidase injected into the optic tectum. cells in the ganglion cell layer were all labelled, while in the amacrine cell layer only 1/4000 cells were labelled. because of such low population, it is unlikely to penetrate displaced ganglion cells by microelectrodes. the present finding suggests that the spiking cells frequently recorded in the inner nuclear layer are genuine amacrine cell ... | 1978 | 19605210 |
| improvements in the benzidine dihydrochloride horseradish peroxidase method. | | 1978 | 751293 |
| destruction of a single cell in the central nervous system of the leech as a means of analysing its connexions and functional role. | a method has been devised for killing an individual neurone in the c.n.s. of the leech by injecting it with pronase. the technique has been used to examine the role of individual sensory and motor cells involved in producing reflex movements.1. after a neurone was injected with pronase, either in an intact animal or an isolated ganglion, its cell body lost its resting and action potentials. some hours later the injected cell's axons in the periphery failed to conduct impulses. in the intact anim ... | 1978 | 722515 |
| cerebellar afferents in teleost catfish (ictaluridae). | the cerebellar afferents in the bullhead catfish (teleostei) were labeled by relying on the retrograde transport of horseradish peroxidase (hrp). retrogradely labeled neurons were seen in: spinal cord, lateral cuneate nucleus, inferior olive, reticular nuclei, vestibular nuclei, nucleus subeminentialis, n. lateralis valvulae, locus coeruleus, n. mesencephalicus dorsalis, the basal optic nuclei, and a nucleus at the isthmic level which may be equivalent to the pontine nuclei of birds and mammals. ... | 1978 | 79576 |
| leghemoglobin. low temperature optical spectra of acid and alkaline forms of leghemoglobin(iv). configuration of the heme. | leghemoglobin(iv), the derivative of leghemoglobin at the formal oxidation state iv, when cooled to liquid nitrogen temperature exhibits radically different spectra at acid and alkaline ph. the acid and alkaline forms are freely interconvertible. the optical spectrum of the acid form is closely similar to optical spectra of the red higher oxidation states of horseradish and cytochrome c peroxidases, showing that the configuration of the heme iron is the same throughout this family of compounds. ... | 1978 | 27520 |
| proton nuclear magnetic resonance studies of compounds i and ii of horseradish peroxidase. | | 1978 | 30456 |
| club endings of primary afferent fibres identified by anterograde horseradish peroxidase labelling. an em study. | | 1978 | 19605186 |
| the role of the cell surface in the migration of primordial germ cells in early chick embryos: effects of concanavalin a. | effects of concanavalin a (con a) on the morphology and migration of primordial germ cells (pgcs) in stage-6 to -12 chick embryos were investigated. con a, at a sublethal dose (10 microgram/ml), inhibited migration of pgcs from the germinal crescent area to other parts of the embryo. affected pgcs were more rounded without the usual cytoplasmic extensions, but the integrity of other structures was unaffected. nearly identical results were obtained with another lectin, wheat germ agglutinin (10 m ... | 1978 | 702035 |
| the organization of neocortical projections from the ventroposterior thalamic complex in the marsupial brush-tailed possum, trichosurus vulpecula: a horseradish peroxidase study. | retrograde transport of horseradish peroxidase (hrp) was used to determine the extent and some of the organizational details of the cortical projection of the ventroposterior thalamic complex (vp) in the marsupial brush-tailed possum, trichosurus vulpecula. the cortical projection field of vp is coincident with si as determined by electrophysiological methods, and would appear not to overlap fully the primary motor cortex. thus, in trichosurus it appears that the motor and somatic sensory cortic ... | 1978 | 689987 |
| localization of concanavalin a binding sites on the cell membrane of herpetomonas samuelpessoai: influence of growth conditions. | herpetomonas samuelpessoai agglutinates when incubated with concanavalin a (con a). agglutination involved binding of con a to specific receptors as it was inhibited by alpha-methyl-d-mannoside. the pattern and the intensity of the agglutination as well as the localization of con a-binding sites were influenced by the composition of the growth medium, growth temperature and time of incubation. con a-binding sites were detected by using the con a-horseradish peroxidase-diaminobenzidine technique. | 1978 | 567601 |
| use of horseradish peroxidase to block nonspecific enzyme uptake in immunoperoxidase microscopy. | intrinsic tissue peroxidase activity can be more or less successfully destroyed by methanol-h2o2 treatment. it has been found, however, in our laboratory that horseradish peroxidase (hrp) coupled to antibody will bind to some tissue components on a nonspecific basis and remain to take part in the histochemical stain. this contributes considerably to the background. this difficulty can be largely overcome if the tissues are pretreated with a solution of horseradish peroxidase which binds with non ... | 1978 | 357648 |
| [chemical modification of lysine epsilon-nh2-groups in horseradish peroxidase. its effect on enzyme stability. temperature dependence of thermo-inactivation constants for native and modified peroxidase]. | thermostability of horseradish peroxidase modified by acetic, propionic, butyric, valeric and succinic anhydrides and trinitrobenzolsulfonic acid (tnbs) is studied within the temperature range of 56-80 degrees c. acylation of 4 amino groups and arylation of 3 amino groups with tnbs are found to stabilize the enzyme, while modification of 6 groups decreases the enzyme stability. chemical modification of peroxidase does not change its ph-dependence with respect to enzyme thermostability. thermodyn ... | 1978 | 32926 |
| unusually fast ligand exchange rate in horseradish peroxidase as studied by temperature-jump method. | | 1978 | 697854 |
| retinotectal compression in the hamster: a quantitative study with horseradish peroxidase [proceedings]. | | 1978 | 690904 |
| a sensitive method for histochemical demonstration of horseradish peroxidase in neurons following retrograde axonal transport. | a study was made on the effects of various fixatives and some other histochemical parameters used in the procedure for demonstrating labeled neurons following retrograde axonal transport of horseradish peroxidase (hrp). the enzyme was injected into the tongue of adult mice and the results were obtained by counting labeled hypoglossal neurons following certain variations in the procedure. paraformaldehyde in the fixative should be avoided since it reduces the number of labeled neurons as compared ... | 1978 | 77707 |
| extraocular muscle representation in the brainstem of the carp. | the representation of the extraocular muscles in the oculomotor nuclei in the brainstem of the carp was studied with the horseradish peroxidase technique. some normal anatomical features of the various oculomotor nuclei are described. following intramuscular hrp injections in the eye muscles and applying survival times of up to 25 days labeled perikarya were found in the various nuclei of the oculomotor complex. rectus inferior, rectus internus, and obliquus inferior are represented in the ipsil ... | 1978 | 641230 |
| topographic projections between the nucleus isthmi and the tectum of the frog rana pipiens. | the connections between the nucleus isthmi and the tectum in the frog have been determined by several anatomical techniques: iontophoresis of horseradish peroxidase into the tectum, iontophoresis of 3h-porline into the nucleus isthmi and the tectum, and fink-heimer degeneration staining after lesions of the nucleus isthmi. the results show that the nucleus isthmi projects bilaterally to the tectal lobes. the ipsilateral isthmio-tectal fibers are distributed in the superficial layers of the tectu ... | 1978 | 305927 |
| [kinetics and mechanism of nucleophilic effect on the oxidation of o-dianisidine catalyzed by horseradish peroxidase]. | the effects of benzimidazole and 4-nitroimidazole on the reaction of o-dianisidine peroxidase oxidation within the ph range of 3.7--9.0 were studied. both substituted imidazoles activate the reaction at less than 0.6. in the presence of 4-nitroimidazole the activation is non-competitive, whereas in the presence of benzimidazole it is of a mixed type, which is close to the non-competitive one. the kinetic parameters (kacat, alpha, ka) for the reaction activated by both imidazoles were determined. ... | 1978 | 27245 |
| mechanism of n-demethylation of aminopyrine by hydrogen peroxide catalyzed by horseradish peroxidase, metmyoglobin, and protohemin. | | 1978 | 667019 |
| an autoradiographic study of midbrain-diencephalic projections to the inferior olivary nucleus in the opossum (didelphis virginiana). | techniques of intra-axonal transport were utlizied to elucidate the organization of diencephalic and midbrain projections to the inferior olivary nucleus of the virginia opossum. retrograde transport of horseradish peroxidase injected into the olive suggests that terminals within it arise from the subparafascicular nucleus of the caudal thalamus, the nucleus of darkschewitsch, the fields of forel, the interstitial nucleus of cajal, the periaqueductal grey, the caudal pretectal nucleus, the tegme ... | 1978 | 641221 |