| in vitro labeling of axonal projections in the mammalian central nervous system. | horseradish peroxidase crystals or hrp-np40 detergent chips were directly applied to brain slices from mice to label primary afferent fibers and their terminal arbors in the brainstem trigeminal complex, and neurons of the ventrobasal complex of the thalamus, their axons in the internal capsule, and their terminals in the primary somatosensory cortex. anterograde and retrograde labeling of fibers, as well as retrograde labeling of somata, were observed. in vitro labeling of selected non-trigemin ... | 1986 | 2425193 |
| a possible model of hemoprotein-peroxide complexes formed in an iron-tetraphenylporphyrin system. | a ferric low-spin species with an anomalously small g3-g1 separation generated by the reaction of fe(iii)tetraphenylporphyrin with t-butylhydroperoxide in the presence of tatramethylammonium hydroxide was characterized by esr spectroscopy. the reaction kinetics, investigated by monitoring esr intensity, indicated that this low-spin complex is highly reactive and easily changed to non-heme type iron complexes. the rhombic parameters of this complex are very similar to those of heme-peroxide adduc ... | 1986 | 3008750 |
| tectal projection neurons to the retinopetal nucleus in the filefish. | following horseradish peroxidase (hrp) injections into the preoptic retinopetal nucleus (prn), neurons in the ipsilateral optic tectum were labeled retrogradely. labeled neurons exhibited a 'golgi-like' appearance, somata of these neurons were pyriform or round, and most of them were located in the stratum album centrale (sac) or the stratum periventriculare (spv). these neurons had a long apical dendrite, which ramified in the upper-half of sgc into horizontally arborized dendritic fields. the ... | 1986 | 3697743 |
| x-ray absorption studies of myoglobin peroxide reveal functional differences between globins and heme enzymes. | x-ray absorption studies of myoglobin peroxide show that although it is not identical with compound i or ii of horseradish peroxidase [chance, b., powers, l., ching, y., poulos, t., yamazaki, i., & paul, k. g. (1984) arch. biochem. biophys. 235, 596-611], it has some structural features in common with both. as seen in compound i, the fe-o distance is short, but the iron-pyrrole nitrogen distance is contracted with a longer iron-histidine distance like compound ii. the iron has a higher oxidation ... | 1986 | 3964675 |
| cytochrome c peroxidase compound es is identical with horseradish peroxide compound i in iron-ligand distances. | x-ray absorption studies of compound es of cytochrome c peroxidase show a short iron-oxygen distance of 1.67 +/- 0.04 a, an iron-histamine distance of 1.91 +/- 0.03 a, and an iron-pyrrole nitrogen average distance of 2.02 +/- 0.02 a. this is identical within the error with the reported structure of horseradish peroxidase compound i [chance, b., powers, l., ching, y., poulos, t., yamazaki, i., & paul, k. g. (1984) arch. biochem. biophys. 235, 596-611]. comparisons of the structures of myoglobin p ... | 1986 | 3008825 |
| morphology and physiology of the brainstem nuclei controlling the electric organ discharge in mormyrid fish. | the motoneurons to the mormyrid electric organ are driven from the medullary relay nucleus. this nucleus is in turn innervated by an adjacent cell group, nucleus c. the goals of this study were to characterize the morphology and physiology of neurons in these two nuclei, and to test the hypothesis that nucleus c is the command nucleus responsible for initiating the electric organ discharge. medullary relay neurons and nucleus c neurons were recorded intracellularly and labeled with horseradish p ... | 1986 | 3700711 |
| optic tectum of the eastern garter snake, thamnophis sirtalis. v. morphology of brainstem afferents and general discussion. | brainstem neurons that project to the optic tectum of the eastern garter snake were identified by retrograde transport of horseradish peroxidase. the distribution and morphology of tectal afferent axons from the thalamus, pretectum, nucleus isthmi, and midbrain reticular formation were then studied by anterograde transport of horseradish peroxidase. diencephalic projections to the tectum arise from the ventral lateral geniculate complex ipsilaterally and the ventrolateral nucleus, suprapeduncula ... | 1986 | 3700709 |
| connections of the pigeon dorsomedial forebrain studied with wga-hrp and 3h-proline. | the afferent-efferent connections of the pigeon dorsomedial forebrain, which is composed of the "hippocampus" (hp) and "parahippocampus" (aph), presumed homologues of the mammalian hippocampal complex, were studied. afferent projections were identified by wheat germ agglutinin-conjugated horseradish peroxidase (wga-hrp) and efferent projections were identified by 3h-proline and wga-hrp. in addition to identified intrinsic connections within hp and aph, both hp and aph were found to be in receipt ... | 1986 | 2422224 |
| optic tectum of the eastern garter snake, thamnophis sirtalis. iv. morphology of afferents from the retina. | the morphology of single retinal terminals in the optic tectum of the eastern garter snake was demonstrated by orthograde filling from extracellular injections of horseradish peroxidase (hrp) into the optic tract. hrp-filled terminals share a characteristic shape and structure. their parent axons course caudally in the stratum opticum within fascicles of 200-300 fibers of varying diameters. single axons exit a fascicle and course into either the stratum fibrosum et griseum superficiale, ventrall ... | 1986 | 3958248 |
| optic tectum of the eastern garter snake, thamnophis sirtalis. iii. morphology of intrinsic neurons. | extracellular iontophoretic injections of horseradish peroxidase and golgi preparations were used to study the distribution and morphology of intrinsic neurons of the garter snake optic tectum. four morphologically distinct classes of neurons were identified. the type a neuron is found throughout the retinorecipient tectal layers. it has a large, fusiform soma and infrequently branching dendrites that radiate in the horizontal plane and are studded with varicose appendages. an axon arises from t ... | 1986 | 3958247 |
| biochemical and morphological correlates of transmitter type in c2, an identified histaminergic neuron in aplysia. | there is compelling evidence that histamine serves as a neurotransmitter in c2, a pair of symmetrical neurons in the cerebral ganglion of aplysia californica. these cells had previously been shown to contain high concentrations both of histamine and of its biosynthetic enzyme, histidine decarboxylase; in addition, 3h-histamine injected intrasomatically was found to move along c2's axons by fast transport. furthermore, several actions of c2 on identified follower cells were simulated by the appli ... | 1986 | 2420844 |
| simultaneous labelling of two different central nervous system pathways with horseradish peroxidase and cobalt in gnathonemus petersii and rana esculenta. | a new and simple simultaneous labelling procedure is described that gives the possibility of studying interneuronal connections and territorial overlap of different pathways. this method uses horseradish peroxidase (hrp) labelling in combination with the cobalt-filling technique. the blue colour of the hrp reaction end-product formed from 0-tolidine (neuroscience, 4 (1979) 1805-1852) and the dark brown of cobalt-filled neurons and their processes allow easy distinction of the two different label ... | 1986 | 3485778 |
| a solid-phase enzyme immunoassay for the common and subtypic determinants of hepatitis b surface antigen with monoclonal antibodies. | monoclonal antibodies were raised against the common (a) as well as subtypic determinants (d, y, w and r) of hepatitis b surface antigen (hbsag). they were applied to subtyping hbsag by sandwiching it between antibody against a fixed on a solid-phase support and antibody against one or other of d, y, w and r, linked to horseradish peroxidase. the assay was applied to evaluate antigenic specificities of the nih and japanese panels composed of 44 sera containing hbsag particles of various subtypes ... | 1986 | 2419452 |
| optic tectum of the eastern garter snake, thamnophis sirtalis. ii. morphology of efferent cells. | tectal efferent neurons were retrogradely filled from extracellular injections of horseradish peroxidase (hrp) into pathways efferent from the tectum. tectorotundal neurons have cylindrical dendritic trees, 80-100 microns in diameter, that extend vertically across the central and superficial tectal layers. apical and basal dendrites are laden with complex appendages. the axon gives rise to an intratectal, collateral arbor that extends horizontally into the stratum griseum centrale beyond the cel ... | 1986 | 3514694 |
| three-dimensional representation and cortical projection topography of the nucleus basalis (ch4) in the macaque: concurrent demonstration of choline acetyltransferase and retrograde transport with a stabilized tetramethylbenzidine method for horseradish peroxidase. | ninety-six percent of the nucleus basalis neurons that project to the neocortex contain choline acetyltransferase. these projections from the cholinergic component of the nucleus basalis (ch4) are topographically organized so that each cortical area receives most of its cholinergic input from a different ch4 sector. the three-dimensional reconstruction of these sectors reveals the presence of a complex structure. a stabilization procedure that was used in these experiments maintains all the adva ... | 1986 | 3516304 |
| time dependent differential yield as a scale-up parameter in enzyme and fermentation reactors. | the yield function, for an enzyme-substrate kinetic model of the system, is investigated. considering y to be a function of the substrate concentration s, its value as s --> o(+) is investigated.in the "pseudo-steady-state domain," this differential yield function is shown to be bounded above and below by yield functions that are obtained by using the michaelis-menten and briggs-haldane functions to relate the enzyme-substrate concentration c to s. it is also shown that the yield constant, which ... | 1986 | 20568184 |
| enzymatic analyses in organic solvents. | horseradish peroxidase has been found to vigorously act as a catalyst in a number of water-immiscible organic solvents. the rates of peroxidase-catalyzed oxidation of p-anisidine with h(2)o(2) in toluene, benzene, ethyl and butyl acetates, and ether are in the range of 10-25% of that in water (ph 7.0) at the same reactant concentrations. per oxidase was coupled with cholesterol oxidase (which was also found to be catalytically active in organic media), and the bienzymic system was successfully u ... | 1986 | 18555343 |
| the accessory nerve nucleus in the baboon. | in the savanna baboon, papio cynocephalus, the accessory nerve nucleus was identified by using a mixture of 20% free horseradish peroxidase (hrp) and 2.5% hrp conjugated to wheat germ agglutinin (wga) in a 5% aqueous detergent solution (nonidet p-40). following surgical exposure of the appropriate nerve branch to the sternocleidomastoid or trapezius muscle, the nerve was transected, placed in an argyle tubing collar, and bathed in 5-10 microliter of the tracer. after a 48-hour survival time and ... | 1986 | 3963427 |
| localization and stimulation of chromatophore motoneurones in the brain of the squid, lolliguncula brevis. | the relatively simple chromatophore system of the squid, lolliguncula brevis, was studied with combined behavioural, morphological and electrophysiological methods in order to understand how the chromatophore patterns in the skin are organized at the level of the posterior chromatophore lobes (pcl). there are nine simple chromatic components of patterning in l. brevis. retrograde transport of horseradish-peroxidase from chromatophores in the mantle skin established that the chromatophore motoneu ... | 1986 | 3958673 |
| optic tectum of the eastern garter snake, thamnophis sirtalis. i. efferent pathways. | extracellular, iontophoretic injections of horseradish peroxidase were used to anterogradely fill axons efferent from the optic tectum in garter snakes. the tectal efferent pathways consist of six axon types with distinct projections and terminal morphologies. tectogeniculate axons pass into the diencephalon via the optic tract, bearing collaterals that form spatially restricted, rodlike arbors in the pretectum, the ventral lateral geniculate nucleus, and the ventrolateral nucleus. tectoisthmi a ... | 1986 | 3958240 |
| median eminence equivalence of the neurohypophysis of the hagfish, eptatretus burgeri. | three substances of different molecular size were injected into the ventricular space (iii) of the neurohypophysis of anesthetized hagfish, eptatretus burgeri, to learn whether such substances could diffuse across the connective tissue barrier between the neuro- and adenohypophysis. the substances tested were trypan blue, a vital dye that is a fine particulate colloid; horseradish peroxidase (hrp), an enzyme protein whose distribution in tissue can be revealed through its chromogenic action on a ... | 1986 | 3956989 |
| reactive intermediates from 3-hydroxybenzo[a]pyrene and its glucuronide. | 3-hydroxybenzo[a]pyrene (3-oh-bap) is oxidized by the horseradish peroxidase/h2o2 system to benzo[a]pyrene-3,6-quinone. in the presence of n-acetylcysteine one other product is also formed. this was identified by its chemical, and u.v., mass and n.m.r. spectral properties as 6-(h-acetyl-cystein-s-yl)-3-hydroxybenzo[a]pyrene (6-nac-cys-3-oh-bap). replacement of the n-acetylcysteine by glutathione leads to the formation of a 3-oh-bap-glutathione adduct. enzymic hydrolysis of benzo[a]pyrene-3-glucu ... | 1986 | 3948331 |
| cortical granule exocytosis is coupled with membrane retrieval in the egg of brachydanio. | activation of the teleost (brachydanio) fish egg includes the exocytosis of cortical granules, the construction of a mosaic surface consisting of the unfertilized egg plasma membrane and the limiting membranes of the cortical granules, and the appearance of coated and smooth vesicles in the cytoplasm (donovan and hart, '82). unfertilized and activated eggs were incubated in selected extracellular tracers to (1) determine experimentally if cortical granule exocytosis was coupled with the endocyto ... | 1986 | 3701295 |
| an evidence of the peroxidase-dependent oxygen transfer from hydrogen peroxide to sulfides. | horseradish- and chloro-peroxidase catalyzed oxidation of sulfides have been investigated. thioanisoles were oxygenated to the corresponding sulfoxides by such peroxidases at the expense of h2o2. dealkylation was observed only in the chloroperoxidase-dependent oxidations of p-methoxy- and p-iso-propoxy-thioanisoles. the experiments with 18o-labeled h2o2 indicated that an oxygen atom of h2o2 is incorporated into the sulfoxides. these research lead to the conclusion that compound i or ii is capabl ... | 1986 | 3954766 |
| peroxidative free radical formation and o-demethylation of etoposide(vp-16) and teniposide(vm-26). | the peroxidative activation of the antitumor drugs, etoposide (vp-16) and teniposide (vm-26), has been studied in vitro. both of these drugs, in the presence of horseradish peroxidase or prostaglandin synthetase, formed phenoxy radical intermediates. furthermore, this activation also resulted in the formation of two metabolites from each of the drugs. using hplc and mass spectrometry, one of the metabolites was shown to be the reactive o-quinone derivative of the parent drug which resulted from ... | 1986 | 3006680 |
| heme-linked ionizations in horseradish peroxidase detected by raman difference spectroscopy. | heme-linked ionizations of the acidic and basic isoenzymes of ferrous horseradish peroxidase influence both the fe-histidine stretching mode and the oxidation-state marker line. first, raman difference spectroscopy of horseradish peroxidase confirms earlier work showing that v(fe-his) undergoes a transition in frequency with a pk that is characteristic of the enzyme's functional properties. the fe-histidine mode shifts by about 2.5-3.0 cm-1 for horseradish peroxidase c and by about 6 cm-1 for th ... | 1986 | 3944105 |
| one- and two-electron oxidation of reduced glutathione by peroxidases. | the oxidation of glutathione by horseradish peroxidase forms a thiyl free radical as demonstrated with the spin trapping esr technique. reactions of this thiyl free radical result in oxygen consumption, which is inhibited by the radical trap 5,5-dimethyl-1-pyrroline-n-oxide. in contrast to l-cysteine oxidation, glutathione oxidation is highly hydrogen peroxide-dependent. the oxidation of glutathione by glutathione peroxidase forms glutathione disulfide without forming a thiyl radical intermediat ... | 1986 | 3003079 |
| a kinetic method for the simultaneous determination of isoenzymes activities in mixture. application to a2 and a3 horseradish peroxidases. | a graphical method for the simultaneous determination of the activity of two isoenzymes in a mixture, is presented. the method is based on the different kinetic behaviour of the isoenzymes to the changes in the substrate concentrations. having determined the reaction rates for the enzyme mixture at different substrate concentrations, the activity of both isoenzymes can be derived graphically. an algebraic method for two or more isoenzymes is mentioned, as well. the applications of the graphical ... | 1986 | 3964285 |
| biotinylated proteins as molecular weight standards on western blots. | protein molecular weight standards were biotinylated by reaction with biotinyl-n-hydroxysuccinimide ester. the biotinylated proteins were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrophoretically transferred to nitrocellulose paper. the resolved protein bands were detected by formation of a streptavidin-biotin/horseradish peroxidase complex and reaction with 4-chloro-1-naphthol and hydrogen peroxide. the biotinylated proteins are easy to prepare and are useful ... | 1986 | 3963367 |
| horseradish peroxidase-catalyzed oxidation of acetaminophen to intermediates that form polymers or conjugate with glutathione. | horseradish peroxidase catalyzed the polymerization of acetaminophen. addition of reduced glutathione (gsh) to reaction mixtures resulted in decreased polymerization and formation of minor amounts of gsh-acetaminophen conjugates. the conjugates were identified as 3-(glutathion-s-yl)acetaminophen and 3-(glutathion-s-yl)diacetaminophen. horseradish peroxidase also catalyzed polymerization of synthetic 3-(glutathion-s-yl)acetaminophen to a dimer conjugate. in contrast to acetaminophen, 3-(glutathio ... | 1986 | 3951429 |
| anatomy of the gustatory system in the hamster: synaptology of facial afferent terminals in the solitary nucleus. | the solitary nucleus is the first level of the central nervous system where processing of taste information can occur. a structural basis for that processing was investigated. facial taste afferent axons were labelled by application of horseradish peroxidase to either the chorda tympani or the geniculate ganglion. the labelled afferent fibers in the rostral solitary nucleus were studied with light and electron microscopy. preterminal facial taste afferent axons enter the nucleus from the solitar ... | 1986 | 3950091 |
| oxygenation of organosulfur compounds by peroxidases: evidence of an electron transfer mechanism for lactoperoxidase. | the oxygenation of benzyl methylsulfide, thioanisole, and thiobenzamide to the respective sulfoxides was found to be catalyzed by chloroperoxidase, lactoperoxidase, and horseradish peroxidase. the activities of lactoperoxidase and horseradish peroxidase were similarly low toward benzyl methylsulfide and thioanisole but lactoperoxidase efficiently catalyzed the oxygenation of thiobenzamide while horseradish peroxidase showed low activity. chloroperoxidase had high reactivity toward all three subs ... | 1986 | 3947087 |
| internalization of cationized ferritin by isolated pancreatic acinar cells. | the internalization of cationized ferritin (cf) was studied in isolated pancreatic acinar cells in vitro. horseradish peroxidase (hrp) was used in conjunction with cf to compare internalization of soluble-phase and membrane-bound tracers. the mode of internalization of cf was dependent upon tracer concentration and origin of the plasma membrane (apical vs. lateral-basal). at the lower tracer concentrations (0.19 and 0.38 mg/ml), internalization from the apical cell surface occurred via small ves ... | 1986 | 3944455 |
| altered endocytosis in a mutant of lm fibroblasts defective in cell-cell fusion. | mutants of lm fibroblasts selected for their decreased ability to undergo polyethylene glycol-induced cell-to-cell fusion (f40 subline) were examined for possible alterations of their ability to carry out endocytosis. both fluid-phase endocytosis of inulin and horseradish peroxidase and nonreceptor mediated adsorptive endocytosis of poly(l-lysine) were reduced to 60% of control values. comparable results were obtained when the uptake of poly(l-lysine) was measured as internalization of surface-b ... | 1986 | 3944203 |
| modulation by applied electric fields of purkinje and stellate cell activity in the isolated turtle cerebellum. | quasi steady-state electric fields were applied across the isolated turtle cerebellum to study the relationship between applied field, neuronal morphology and the modulation of the neuronal spike firing pattern. spiking elements were identified electrophysiologically using extracellular recording methods and by subsequent horseradish peroxidase injection, which revealed their dendritic morphology and orientation. the electric field was precisely defined by measuring the voltage gradients induced ... | 1986 | 3701658 |
| probabilistic determination of synaptic strength. | this work was carried on to analyze the presynaptic components of synaptic efficacy, which is designated by the term of synaptic strength. to assess the relations between synaptic strength and innervation density, the properties of unitary cl(-)-dependent inhibitory postsynaptic potentials (ipsps) evoked in the potentials (ipsps) evoked in the goldfish mauthner (m-) cell by single impulses in individual presynaptic cells, including quantal release parameters, were compared with the histological ... | 1986 | 3005523 |
| the transneuronal transport of horseradish peroxidase in the visual system of the frog, rana pipiens. | during the course of experiments designed to study synaptic relationships between the terminals of retinal axons and the various cell populations in the optic tectum of the frog, rana pipiens, we found that neurons in many of the retinorecipient nuclei, including the tectum, are labeled transneuronally following injections of horseradish peroxidase into the optic nerve. in the optic tectum, particular cell groups are labeled to the extent that their dendrites as well as their somas are filled wi ... | 1986 | 2422588 |
| external atp permeabilizes transformed cells to macromolecules. | external atp under certain ionic conditions render transformed cells permeable to the translation inhibitor hygromycin b. with this method the protein toxin alpha-sarcin selectively penetrates into 3t6 cells, as compared to 3t3 cells. this entry is enhanced by atp synthesis blockers such as cccp. other proteins, such as horseradish peroxidase and luciferase, also pass selectively in 3t6 cells under permeabilization conditions. | 1986 | 3947333 |
| a rapid and simple immunoperoxidase staining procedure for blood and bone marrow samples. | a fast and simple indirect immunoperoxidase staining technique is described, which can also be used for the characterization of cells with high endogenous peroxidase activity such as many haemopoietic cells. it is based on the combination of a newly developed glucose-oxidase plus glucose procedure for the inhibition of endogenous peroxidase activity with a standard 2 or 3 layer immunoperoxidase staining protocol. glucose-oxidase plus glucose mixture completely inhibits endogenous peroxidase acti ... | 1986 | 2418120 |
| the origin, course, and termination of the hippocampothalamic projections in the macaque. | the projections from the hippocampal formation to the thalamus were investigated with both anterograde and retrograde tracers. horseradish peroxidase was injected into medial and midline thalamic sites in six cases, and tritiated amino acids were injected into the hippocampal formation in nine others, five of which had prior transections of the fornix. only the subicular and entorhinal cortices were found to project to the thalamus. from the subicular cortex, dense bilateral projections were tra ... | 1986 | 3512627 |
| organization of the efferent vestibular nuclei and nerves of the toadfish, opsanus tau. | the efferent vestibular nuclei and nerves were studied in the toadfish, opsanus tau, with morphological and electrophysiological techniques. the origin and course of the efferent vestibular nerves was extensively documented. one major morphological observation was that the efferent nerves comprise a peripheral network that is anatomically distinct, and separable by dissection from the primary afferents innervated by each end organ. these anatomically distinct nerves are likely to be a major asse ... | 1986 | 2869067 |
| heterogeneity of neurons in the crustacean x-organ as revealed by intracellular recording and injection of horseradish peroxidase. | the intracellular injection technique of hrp with simultaneous recordings of intracellular potential was applied to the crab x-organ-sinus gland peptidergic neurosecretory neurons. at least two classes of neurons were discriminated from the usual type of neurosecretory neurons morphologically as well as electrophysiologically. possible roles of those neurons were suggested as the modulation and coordination of activities of the neurosecretory system. | 1986 | 3942890 |
| connections of the lateral cortex in the lizard podarcis hispanica. | the connections of the lateral cortex of the lizard podarcis hispanica have been traced using horseradish peroxidase transport techniques. after injections, restricted to the lateral cortex, labelled neurons can be observed bilaterally in the main olfactory bulbs and the diagonal band, contralaterally in the lateral cortex and ipsilaterally in the nucleus of the lateral olfactory tract, the ventral amygdaloid nucleus and also in the area triangularis. an efferent has also been shown on the ipsil ... | 1986 | 2419802 |
| oxidase reactions of tomato anionic peroxidase. | tomato (lycopersicon esculentum mill) anionic peroxidase was found to catalyze oxidase reactions with nadh, glutathione, dithiothreitol, oxaloacetate, and hydroquinone as substrates with a mean activity 30% that of horseradish peroxidase; this is in contrast to the negligible activity of the tomato enzyme as compared to the horseradish enzyme in catalyzing an indoleacetic acid-oxidase reaction with only mn(2+) and a phenol as cofactors. substitution of ce(3+) for mn(2+) produced an 18-fold large ... | 1986 | 16664567 |
| the structural and functional characteristics of striate cortical neurons that innervate the superior colliculus and lateral posterior nucleus in hamster. | intracellular recording and horseradish peroxidase injection techniques were used to structurally and functionally characterize the striate cortical neurons in hamster that projected to the superior colliculus and/or lateral posterior nucleus of the thalamus. with two exceptions, the receptive field properties and morphological characteristics of the neurons antidromically activated from the colliculus and lateral posterior nucleus were quite similar. striate corticotectal and striate cortico-la ... | 1986 | 3960316 |
| cyclic formation and decay of the blood-testis barrier in the mink (mustela vison), a seasonal breeder. | the correlations between the germ cell population and the blood-testis barrier were studied during puberty and throughout the reproductive cycle in a seasonal breeder, the mink. a classification of 12 stages, corresponding to the cellular associations appearing during the cycle of the seminiferous epithelium, was proposed and used to identify the stages of the cycle in pubertal mink. in adult mink, the reproductive cycle was divided into two spermatogenic phases--an active phase lasting 9 months ... | 1986 | 3953473 |
| enhanced chemiluminescent reactions catalyzed by horseradish peroxidase. | enhancement of light emission from the horseradish peroxidase-catalyzed oxidation of diacyl hydrazides on addition of 6-hydroxybenzothiazole or phenol derivatives forms the basis of rapid, specific, and sensitive chemiluminescent assays for peroxidase. the advantages and wide applicability of the technique have been demonstrated in a range of ligand-binding assays. careful selection of chemiluminescent reagents, enhancer, their relative proportions and reaction conditions, and more detailed know ... | 1986 | 3821542 |
| detection of specific anti-hapten antibody-producing hybridoma cells in tissue sections of spleen and liver by hapten-enzyme conjugates using an immunoenzyme approach. | a method is presented for the detection of hybridoma cell growth in vivo by making use of the specific antigen (hapten) recognition properties of the produced monoclonal antibodies. horseradish peroxidase (hrp)-labeled antigen was used for demonstration of intracellular specific antibodies in hybridoma cells. it appeared that intravenously injected anti-penicilloyl-producing hybridoma cells developed mainly in the red pulp of the spleen; to a lesser extent they were found in the liver. | 1986 | 3804360 |
| labelled neurons in mesencephalon and medulla oblongata of newt after periocular injection of horseradish peroxidase. | the retrograde transport of hrp after periocular space injection was investigated in mesencephalon and medulla oblongata of newt brain. in the tegmentum the neurons of oculomotor and troclear nucleus are filled. in the optic tectum some filled cells of mesencephalic trigeminal nucleus were, for the first time, described. this suggest that these neurons are deputated to proprioceptive innervation of the extrinsic ocular muscles. in the medulla oblongata the labelled neurons were located in the ga ... | 1986 | 3794320 |
| microscopical and ultrastructural investigations on the development of the blood-brain barrier in the chick embryo optic tectum. | the formation of a blood-brain barrier to horseradish peroxidase was microscopically and ultrastructurally investigated in the tectum opticum of the chick during development of the intraneural blood vessel network from the 6th incubation day to hatching, and in adult specimens. extravasation of the circulating marker, apparently unimpeded during early stages of vasculogenesis, starts to diminish from the 14th incubation day (i.d.) and is prevented after the 18th i.d. the tracer seems to get out ... | 1986 | 3766122 |
| impaired refinement of the regenerated retinotectal projection of the goldfish in stroboscopic light: a quantitative wga-hrp study. | the retinotectal projection of the goldfish was studied after regeneration of a cut optic nerve in stroboscopic light, constant light or diurnal light, with the lens removed to blur the retinal image. retrograde transport of wheatgerm agglutinin, conjugated to horseradish peroxidase, from a standard tectal injection site was used to measure the topographic precision of the projection. the dispersion of labelled retinal ganglion cells, which reflects this precision, was assessed by a method based ... | 1986 | 3758259 |
| topographic refinement of the regenerating retinotectal projection of the goldfish in standard laboratory conditions: a quantitative wga-hrp study. | the topographic precision of the regenerating retinotectal projection of the goldfish was studied between 18 and 524 days (at 20 degrees c) after optic nerve cut, using retrograde transport of wheatgerm agglutinin conjugated to horseradish peroxidase (wga-hrp) from one of two standardized tectal injection sites. all labelled ganglion cells in each flat-mounted retina were plotted individually, and their degree of dispersion was assessed by a statistical method based on distance to nearest neighb ... | 1986 | 3758258 |
| [localization of lectin receptors on the surface of c1300 neuroblastoma cells]. | d-mannose, d-galactose, n-acetyl-d-galactosamine, n-acetyl-d-glucosamine and l-fucose which are sugar determinants of receptors were found on the surface of neuroblastoma cells by means of four carbohydrate-specific lectin groups. labeling of lectins was performed by horseradish peroxidase, ferritin and colloidal gold. peculiarities of the lectin receptors distribution on the surface of immature neuroblastoma cells were detected. | 1986 | 3757884 |
| internalized proteins directed into accumulative compartments of mosquito oocytes by the specific ligand, vitellogenin. | we have investigated the internalization pathways for a specific protein, vitellogenin, and a non-specific protein, horseradish peroxidase, in the mosquito oocyte in vivo. the internalized proteins were localized by electron microscopical immunocytochemistry or autoradiography; the relationship of their destination compartments with lysosomes was monitored by visualization of acid phosphatase. proteins internalized by the oocyte follow either a specific accumulative route or a lysosomal degradat ... | 1986 | 3750316 |
| synapse formation and induction of acetylcholine receptors by spinal neurones in cocultures with sympathetic ganglion and muscle cells. | coculture of chick embryonic sympathetic neurones with spinal cord explants induced an age-dependent increase in the acetylcholine receptor numbers of the ganglion cells. these acetylcholine receptors did not appear to be necessary for the initial formation of spinal cord-ganglion synapses since their blockade with the alpha-bungarotoxin-horseradish peroxidase complex did not prevent synapse formation in culture. the presence of acetylcholine receptors appears to be sufficient for synapse format ... | 1986 | 3743471 |
| end buds: non-ampullary electroreceptors in adult lampreys. | shared anatomical and physiological characters indicate that the low-frequency sensitive electrosensory system of lampreys is homologous with those of non-teleost fishes and amphibians. however, the ampullary electroreceptor organs which characterize all of these gnathostomes are not found in lampreys. experimental anatomical and physiological studies reported here demonstrate that the epidermal end buds are the electroreceptors of adult lampreys. end buds, consisting of both sensory and support ... | 1986 | 3723431 |
| cerebellar afferents in normal and weaver mutant mice. | cerebellar afferents in 3-week-old normal and homozygous weaver mutant mice were investigated using retrograde transport of horseradish peroxidase. almost all afferents found in other mammals were demonstrated in both normal and mutant mice of this age. labelling in the trigeminal nuclei in both mutants and normals was found only in cases in which the ansoparamedian or uvular lobules were included in the injection site, indicating that the projection domains of mossy fiber afferent systems retai ... | 1986 | 3594201 |
| retinal projections in the lizard podarcis hispanica. | the retinofugal of the lizard podarcis hispanica has been examined by means of enzymatic method with horseradish peroxidase (hrp). the retinal ganglion cells project contralaterally to thalamus (nucleus geniculatus lateralis pars dorsalis, nucleus geniculatus lateralis pars ventralis and nucleus ventrolateralis pars ventralis and nucleus ventrolateralis pars ventralis), pretectum (nucleus lentiformis mesencephali, nucleus geniculatus pretectalis and nucleus posterodorsalis) and optic tectum (lay ... | 1986 | 3571966 |
| identification of a nucleus isthmi in the weakly electric fish apteronotus leptorhynchus (gymnotiformes). | the nucleus isthmi of teleost fish, amphibians, reptiles and birds, and its probable homologue, the nucleus parabigeminalis of mammals, share in common certain features such as location in the dorsal tegmentum and reciprocal connectivity with the optic tectum. in gymnotid fish the nucleus isthmi is located dorsolaterally in the brainstem tegmentum, ventral to the torus semicircularis and the lateral mesencephalic reticular area and dorsal to the rostral nucleus praeeminentialis. the nucleus isth ... | 1986 | 3567545 |
| enhanced luminescent quantitation of horseradish peroxidase conjugates: application in an enzyme immunoassay for digoxin. | a p-iodophenol-enhanced luminescent end-point has been incorporated into a commercially available heterogeneous competitive enzyme immunoassay for digoxin based on a horseradish peroxidase-digoxin conjugate. the luminescent end-point could be completed in less than 1 min and significantly reduced overall assay time. results for the assay obtained using enhanced luminescence showed good agreement with those obtained using a colorimetric end-point (correlation coefficient 0.98). both assays gave a ... | 1986 | 3532910 |
| cell death in the retinal ganglion cell layer during optic nerve regeneration for the frog rana pipiens. | cell number in the retinal ganglion cell layer of adult rana pipiens was estimated from cresyl stained wholemounts. values for normal animals ranged from 466,000 to 643,000 but differences between sides of individual animals varied by 9% or less. during optic nerve regeneration, following unilateral extracranial optic nerve crush, cell numbers in experimental retinae fell compared to their unoperated partners with the majority of the loss taking place between 56 and 84 days; by 200 day only half ... | 1986 | 3488614 |
| afferent and efferent components of the facial nerve in a frog, rana pipiens. | the seventh cranial nerve in rana pipiens is a slender nerve with limited peripheral distribution. we investigated the afferent and efferent components of this nerve by labeling its major branch, the hyomandibular, with horseradish peroxidase. the efferent portion of the seventh nerve originates from a small cell group in the upper medulla which contains two subdivisions. afferent fibers carried in nerve vii travel in the solitary tract and the dorsolateral funiculus. the solitary component cons ... | 1986 | 3486046 |
| differences between glycoprotein profiles of normal tear fluid and of tear fluid from patients with primary sjögren's syndrome. | we present a method for tear glycoprotein characterization using lectins as probes. sds-page of samples is followed by electrophoretic transfer of proteins from gels onto nitrocellulose paper. biotinylated lectin is overlayed and visualized with avidin-conjugated horseradish-peroxidase. with the use of 10 lectins, pooled samples of normal tears were assayed and compared to pooled samples of tears from patients with sjögren's syndrome. significant differences in number of bands, molecular weights ... | 1986 | 3473638 |
| oxidation of suitable drugs by horseradish peroxidase/hydrogen peroxide results in the oxygenation of arachidonic acid to form hydroperoxyeicosatetraenoic acids in a reverse co-oxidation process. | | 1986 | 3083660 |
| horseradish peroxidase-catalyzed oxidation of mitoxantrone: spectrophotometric and electron paramagnetic resonance studies. | the clinical anticancer agent mitoxantrone is subject to irreversible oxidation by hydrogen peroxide catalyzed by horseradish peroxidase (hrp). the characteristic absorption changes that result provide evidence for an initial metabolite which is further oxidized enzymatically. the formation of the metabolite is accompanied by the concomitant generation of a free radical species detected by epr spectroscopy. the intensity of the latter is dependent on the ratio of mitoxantrone to oxidant as well ... | 1986 | 3021839 |
| one- and two-electron oxidation of reduced glutathione by peroxidases. | the oxidation of glutathione by horseradish peroxidase or lactoperoxidase forms a thiyl free radical, as demonstrated with the spin-trapping esr technique. reactions of this thiyl free radical result in oxygen consumption, which is inhibited by the radical trap 5,5-dimethyl-1-pyrroline-n-oxide. in contrast to l-cysteine oxidation, glutathione oxidation is highly hydrogen peroxide-dependent. the oxidation of glutathione by glutathione peroxidase forms gssg without forming a thiyl radical intermed ... | 1986 | 3020935 |
| metabolism of diethylstilbestrol by horseradish peroxidase and prostaglandin synthase--evidence for a free radical intermediate. | | 1986 | 3020932 |
| routing of internalized ricin and ricin conjugates to the golgi complex. | receptor-mediated endocytosis and intracellular routing of native ricin, and of ricin conjugated to colloidal gold (ri-au) and to horseradish peroxidase (ri-hrp), have been studied in cultured mcf-7 and vero cells by electron microscopical techniques including serial section analysis. both native ricin, as demonstrated by immunoperoxidase cytochemistry, and the ricin conjugates were internalized via a common coated pit-coated vesicle pathway to reach vacuolar and tubulo-vesicular portions of the ... | 1986 | 3001103 |
| the time-course of appearance and net accumulation of horseradish peroxidase (hrp) presented orally to juvenile carp cyprinus carpio (l.). | a sensitive enzyme-linked immunosorbent assay (elisa) technique was used in order to determine horseradish peroxidase (hrp) uptake from the carp gut. hrp was detected in blood plasma and various tissues within 15 min of oral intubation. the time-course of net accumulation (uptake-degradation) over a 2 hr period was recorded. the presence of hrp reached a maximum in the body tissues approximately 1 hr after intubation and on a microgram/g wet weight basis the order of accumulation within the tiss ... | 1986 | 2875835 |
| neocortical layers i and ii of the hedgehog (erinaceus europaeus). ii. thalamo-cortical connections. | this study examines the thalamo-cortical projections to the most superficial neocortical layers in the hedgehog (erinaceus europaeus) after small injections of horseradish peroxidase and horseradish peroxidase conjugated to wheat germ agglutinin in the somato-sensory cortex. the injections were limited to layers i, ii and upper parts of layer iii/iv. retrogradely labeled cells were plotted in serial sections through the thalamus. injections in the somato-sensory cortex gave a pattern of elongate ... | 1986 | 2435192 |
| the cerebellotectal pathway in the grey squirrel. | in the well laminated superior colliculus of the grey squirrel the cells of origin of the crossed descending pathway to the brainstem gaze centers are contained within the inner sublamina of the intermediate grey layer. the technique of anterograde transport of horseradish peroxidase was used to determine whether the pathway from the cerebellum to the superior colliculus terminates in this region. the technique of retrograde transport of horseradish peroxidase was used to localize the source of ... | 1986 | 2433144 |
| a light- and electron-microscopic study of mesencephalic neurons projecting to the ganglion of the nervus terminalis in the goldfish. | after application of various neuronal tracers (horseradish peroxidase, cobalt-chloride lysine, true blue) to the ganglion of the nervus terminalis a small number of neurons was retrogradely labeled in the mesencephalon. as revealed by combined horseradish peroxidase and catecholamine-fluorescence techniques these neurons are located in the isthmic area immediately rostral to, but not within the locus coeruleus. cobalt-labeled axons of the mesencephalic neurons were traced individually in serial ... | 1986 | 2430717 |
| sensory projections to the nucleus basalis prosencephali of the pigeon. | the afferent pathways to the nucleus basalis prosencephali of the pigeon were studied by use of the horseradish peroxidase (hrp) technique. it was confirmed that this nucleus receives a direct pathway from the nucleus sensorius principalis nervi trigemini and that, as in the starling, it receives a direct input from the nucleus lemnisci lateralis, pars ventralis, an auditory relay. totally novel is the finding that the nucleus basalis prosencephali is the target of a direct pathway originating i ... | 1986 | 2428501 |
| glucose oxidase as label in histological immunoassays with enzyme-amplification in a two-step technique: coimmobilized horseradish peroxidase as secondary system enzyme for chromogen oxidation. | a sensitive staining procedure for glucose oxidase (god) as marker in immunohistology is described. the cytochemical procedure involves a two-step enzyme method in which god and horseradish peroxidase (hrp) are coimmobilized onto the same cellular sites by immunological bridging or by the principle of avidin-biotin interaction. in this coupled enzyme technique, h2o2 generated during god reaction is the substrate for hrp and is utilized for the oxidation of chromogens such as 3,3'-diaminobenzidin ... | 1986 | 2426225 |
| tracing of single fibers of the nervus terminalis in the goldfish brain. | central projections of the nervus terminalis (n.t.) in the goldfish were investigated using cobalt- and horseradish peroxidase-tracing techniques. single n.t. fibers were identified after unilateral application of cobalt chloride-lysine to the rostral olfactory bulb. the central course and branching patterns of individual n.t. fibers were studied in serial sections. eight types of n.t. fibers are differentiated according to pathways and projection patterns. projection areas of the n.t. include t ... | 1986 | 2425980 |
| central connections of the olfactory bulb in the bichir, polypterus palmas, reexamined. | central connections of the olfactory bulb of polypterus palmas were studied with the use of horseradish peroxidase and cobalt-tracing techniques. the olfactory bulb projects to subpallial and pallial areas in the ipsilateral telencephalon; a projection to the contralateral subpallium is noted via the habenular commissure. a further target of secondary olfactory fibers is a caudal olfactory projection area in the ipsilateral hypothalamus. no labeling was seen in the anterior commissure and in the ... | 1986 | 2424609 |
| presynaptic inhibition produced by an identified presynaptic inhibitory neuron. ii. presynaptic conductance changes caused by histamine. | we have examined the morphology and pharmacology of the l32 neurons, identified cells that mediate presynaptic inhibition in the aplysia abdominal ganglion, to gain insight into the putative transmitter released by the l32 cells. we analyzed the fine structure of the synaptic release sites of l32 cells stained with horseradish peroxidase. each varicosity of l32 was found to contain two general classes of vesicles. one class of vesicles is large (mean long diameter of 98 nm) and contains an elect ... | 1986 | 2419525 |
| number and size of motoneurons in a forelimb motor nucleus of normal and dystrophic (c57bl/6j dy2j/dy2j) mice. | the method of retrograde axonal transport of horseradish peroxidase (hrp) was used to identify the motoneurons that innervate the distal forelimb muscles via the ulnar nerve in normal and dystrophic (c56bl/6j dy2j/dy2j) mice. in both normal and dystrophic mice this motor nucleus was located in spinal segments c6 through t1. no clear division, on the basis of size, into alpha and gamma motoneuron populations was apparent. the motoneurons of dystrophic mice were fewer in number (26.5 vs. 35) but l ... | 1986 | 2416586 |
| nature of the macromolecular binding of diethylstilbestrol to dna and protein following oxidation by peroxidase/hydrogen peroxide. | incubation of [14c]diethylstilbestrol ([14c]des) with horseradish peroxidase(hrp)/hydrogen peroxide in the presence of various polynucleotides and proteins led to macromolecular binding of radioactivity. binding to dna proved stable against ethanol precipitation, but was completely removed when the dna was subjected to gel electrophoresis, caesium chloride density centrifugation, and mild hydrolysis. in contrast, binding to protein was stable in gel electrophoresis. the extent of binding did not ... | 1985 | 4075455 |
| site-selected fluorescence spectra of porphyrin derivatives of heme proteins. | the emission spectra of the porphyrin in metal-free and zn cytochrome c and in metal-free mesoporphyrin derivatives of horseradish peroxidases a and c, leghemoglobin, and myoglobin were examined as a function of temperature and excitation wavelength. at room temperature, the emission spectra were unresolved and were independent of excitation wavelength. at low temperature (4.2 k), the spectra depended upon excitation wavelength: using narrow-band excitation into the high-energy side of the 0-1 a ... | 1985 | 3004569 |
| metabolism of diethylstilbestrol by horseradish peroxidase and prostaglandin-h synthase. generation of a free radical intermediate and its interaction with glutathione. | diethylstilbestrol is carcinogenic in rodents and in humans and its peroxidatic oxidation in utero has been associated with its carcinogenic activity. horseradish peroxidase-catalyzed oxidation of [14c]diethylstilbestrol and [14c]diethylstilbestrol analogs induced binding of radiolabel to dna only when the compound contained a free hydroxy group (metzler, m., and epe, b. (1984) chem. biol. interact. 50, 351-360). we have found that horseradish peroxidase or prostaglandin-h synthase-catalyzed oxi ... | 1985 | 2999150 |
| endocytic and exocytic pathways of the neuronal secretory process and trans-synaptic transfer of wheat germ agglutinin-horseradish peroxidase in vivo. | the lectin wheat germ agglutinin (wga) conjugated to horseradish peroxidase (hrp) was employed to study the endocytic and exocytic pathways of the secretory process in neurons and the potential for trans-synaptic transfer of molecules within the cns. wga-hrp binds to surface membrane oligosaccharides and enters cells by adsorptive endocytosis. the lectin conjugate was administered intranasally or into the cerebral ventricles of mice; postinjection survival times ranged from 5 minutes to 6 days. ... | 1985 | 2418083 |
| unique cyanide nitrogen-15 nuclear magnetic resonance chemical shift values for cyano-peroxidase complexes. relevance to the heme active-site structure and mechanism of peroxide activation. | cyanide ion has been utilized to probe the heme environment of the ferric states of horseradish peroxidase, lactoperoxidase and chloroperoxidase. the 15n-nmr signal for cyanide bound to these enzymes is located in the downfield region from 578 to 412 ppm (with respect to the nitrate ion reference). the corresponding signal for met-forms of hemoglobin, myoglobin and cytochrome c is much further downfield in the 1047-847 ppm region. the signal position for peroxidases is quite invariant with ph in ... | 1985 | 4074752 |
| photooxidation of porphyrin in mg-substituted horseradish peroxidase. | upon photoirradiation under aerobic conditions, the porphyrin prosthetic group in mg-substituted horseradish peroxidase was oxidized to a mixture of its pi-cation radical and an oxidized product with an absorption band at 448 nm. the 448 nm compound was then converted to a 489 nm compound in the dark and the activation energy for the conversion was 19.3 kcal/mol. about 1 mol of o2 was consumed per mol of the 448 nm compound formed and no o2 consumption was seen in the dark reaction. the substitu ... | 1985 | 2999121 |
| preparation and properties of ferrous chloroperoxidase complexes with dioxygen, nitric oxide, and an alkyl isocyanide. spectroscopic dissimilarities between the oxygenated forms of chloroperoxidase and cytochrome p-450. | extensive spectroscopic investigations of chloroperoxidase and cytochrome p-450 have consistently revealed close similarities between these two functionally distinct enzymes. although the co-bound ferrous states were the first to display such resemblance, additional comparisons have focused on the native ferric and ferrous and the ligand-bound ferric derivatives of the enzymes. in order to test the extent to which the spectral properties of the two enzymes match each other, we have prepared the ... | 1985 | 2999120 |
| spectral properties of the higher oxidation states of prostaglandin h synthase. | prostaglandin h (pgh) synthase reacts with organic hydroperoxides and fatty acid hydroperoxides on a millisecond time scale to generate an intermediate that is spectrally similar to compound i of horseradish peroxidase. compound i of pgh synthase is converted to compound ii within 170 ms. compound ii decays to resting enzyme in a few seconds. thus, the peroxidase reaction of pgh synthase appears to involve a cycle of native enzyme, compound i, and compound ii, typical of heme-containing peroxida ... | 1985 | 3934150 |
| phorbol myristate acetate induces endocytosis as well as exocytosis and hydroosmosis in toad urinary bladder. | the induction of the hydroosmotic response in the toad urinary bladder is considered to be associated with membrane addition mediated by exocytosis at the affected luminal membrane and reversed by endocytic retrieval at that surface. the permeability, exocytosis and endocytosis are initiated by antidiuretic hormone (adh) receptor interaction on the basolateral membrane. in other hormone responsive systems, phorbol ester (phorbol myristate acetate, pma), a tumor promoter, has been implicated in t ... | 1985 | 3933562 |
| the generation and subsequent fate of glutathionyl radicals in biological systems. | horseradish peroxidase-catalyzed oxidation of p-phenetidine in the presence of either glutathione (gsh), cysteine, or n-acetylcysteine led to the production of the appropriate thioyl radical which could be observed using epr spectroscopy in conjunction with the spin trap 5,5-dimethyl-1-pyrroline-n-oxide. this confirms earlier work using acetaminophen (ross, d., albano, e., nilsson, u., and moldéus, p. (1984) biochem. biophys. res. commun. 125, 109-115). the further reactions of glutathionyl radi ... | 1985 | 2999101 |
| enzymatic reduction of 5-phenyl-4-pentenyl-hydroperoxide: detection of peroxidases and identification of peroxidase reducing substrates. | 5-phenyl-4-pentenyl-hydroperoxide (pphp) is reduced to 5-phenyl-4-pentenyl-alcohol (ppa) by plant and animal peroxidases in the presence of reducing substrates. pphp and ppa are rapidly isolated with solid phase extraction, separated by isocratic reverse-phase high-performance liquid chromatography, and quantitated with a fixed-wave-length ultraviolet detector. the procedure described is suitable for detecting peroxide-reducing enzymes, determining the kinetic properties of heme- and non-heme-co ... | 1985 | 4083906 |
| patterns of peanut agglutinin binding within the developing grasshopper central nervous system. | the location of peanut agglutinin (pna) binding was investigated in the segmental ganglia of the developing grasshopper embryo. neuronal processes were stained but cell bodies were not. the first appearance of pna binding in development was associated with the first neurons to initiate axon outgrowth, the progeny of the mp2 cells. in the early stages of development the location of pna binding was congruent with that of antibodies against horseradish peroxidase (hrp), which bind to neurons. in mo ... | 1985 | 3914535 |
| central projections of primary vestibular fibers in the bullfrog. iii. the anterior semicircular canal afferents. | a study was made of the projection patterns in the vestibular nuclei of primary afferent fibers innervating the crista of the anterior semicircular canal (asc) of the bullfrog. individual neurons were intracellularly recorded to characterize their spontaneous activity and injected with horseradish peroxidase to visualize their central and peripheral projections. a quantitative evaluation was made of the lengths of the central projections of primary afferents in the various vestibular nuclei and ... | 1985 | 3906326 |
| amplified flow-cytometric separation-free fluorescence immunoassays. | an equilibrium-type competitive-binding fluorescence immunoassay with high sensitivity and excellent precision is described that obviates separation of free from bound label. in the assay relatively large (10 microns diameter) antibody-coated non-fluorescent particles and very small (0.10 micron diameter) antigen-coated fluorescent latex particles are used. soluble nonlabeled antigen competes with antigen on the microspheres for antibody binding sites on the larger spheres. after equilibrium is ... | 1985 | 3905066 |
| a simple enzyme-linked immunosorbent assay for testosterone. | a new, enzyme-linked, immunosorbent assay for testosterone is described. the assay uses horseradish peroxidase coupled to testosterone as the tracer and offers the same sensitivity and reliability but greater convenience than radioimmunoassay. the assay is also simpler and more rapidly completed than previously described assays for testosterone. | 1985 | 3842026 |
| ultrastructure of the segmental giant neuron of crayfish. | the ultrastructure of the crayfish segmental giant (sg) neuron is described, and compared to other identified and unidentified crayfish neurons. the sg was specifically stained by intracellular injection of horseradish peroxidase and is divided into four regions of interest. in the dorsal region, finger-like dendrites of the sg make contact with the through-conducting giant fibres (gf). these contacts are physiologically defined rectifying electrical synapses. they are characterized by the prese ... | 1985 | 3831246 |
| physiological aspects of free-radical reactions. | enzymes which catalyze the formation of free radicals in vitro will catalyze similar reactions in vivo. we believe that the formation of some kinds of free radicals has definite physiological meanings in metabolism. in this sense, the enzymes forming such free radicals are concluded to be in evolutionally advanced states. elaborated structure and function of enzymes such as horseradish peroxidase and microsomal flavoproteins support the idea. deleterious and side reactions caused by free radical ... | 1985 | 3007098 |
| generation of reactive species and fate of thiols during peroxidase-catalyzed metabolic activation of aromatic amines and phenols. | the horseradish peroxidase (hrp)-catalyzed oxidation of p-phenetidine and acetaminophen was investigated. studies using the spin probe 2-ethyl-1-hydroxy-2,5,5-trimethyl-3-oxazolidine (oxanoh) suggested these oxidations involve the generation of substrate-derived free radicals. this was confirmed by using glutathione (gsh) in these incubations in the presence of the spin trap 5,5-dimethyl-1-pyrroline-n-oxide (dmpo). dmpo-glutathionyl radical adducts were observed using epr spectroscopy during hrp ... | 1985 | 3007092 |
| intrinsic connections of macaque striate cortex: afferent and efferent connections of lamina 4c. | we have studied the intrinsic organization of macaque striate cortex by tracing the pattern of horseradish peroxidase (hrp)-labeled axons and cell bodies produced by microinjections of hrp into single cortical laminae. both anterograde and retrograde transport results were used to examine: (1) the pattern of projections from lamina 4c to the superficial layers; (2) the projection from lamina 4c to deeper cortical layers; and (3) the projections to lamina 4c from other cortical laminae. laminae 4 ... | 1985 | 3001242 |
| the circadian pacemaker in the aplysia eye sends axons throughout the central nervous system. | each eye of aplysia contains a population of electrically coupled pacemaker neurons whose synchronous activity can be recorded from the optic nerve as a compound action potential (cap). the cap frequency continues to show a circadian rhythm even when the eye is isolated from the animal and maintained in constant conditions, and thus it contains an autonomous circadian pacemaker, which may reside in the pacemaker neurons. the pacemaker neurons, along with retinal photoreceptors, send axons out of ... | 1985 | 3001240 |
| the origins of descending spinal projections in lepidosirenid lungfishes. | the origins of descending spinal projections in the lepidosirenid lungfishes were identified by retrograde transport of horseradish peroxidase (hrp) introduced into the rostral spinal cords of juvenile african (protopterus annectans and protopterus amphibians) and south american (lepidosiren paradoxa) lungfishes. standard hrp histochemistry revealed retrogradely labeled neurons in the nucleus of the medial longitudinal fasciculus, midbrain tegmentum, red nucleus, optic tectum, mesencephalic trig ... | 1985 | 4078041 |
| enhanced chemiluminescent method for the detection of dna dot-hybridization assays. | a simple enhanced chemiluminescent procedure for the quantitation of dna hybridization to dot blots is described. the method utilizes dna probes labeled with biotin, which are detected using a biotinylated streptavidin-horseradish peroxidase complex. the peroxidase enzyme then takes part in an enhanced chemiluminescent reaction with luminol, peroxide, and an enhancer. the method can be used to give quantitative results using a photomultiplier tube or qualitative results by recording the light em ... | 1985 | 4091282 |