| evidence for visual mapping in the peduncle lobe of octopus. | the first use of horseradish peroxidase in the central nervous system of a cephalopod revealed apparent topographic connections between optic and peduncle lobes in octopus. optic lobe efferent fibers within the peduncle lobe neuropil and labeled cells in the peduncle lobe exhibited alignment along the anteroposterior and dorsoventral axes of the peduncle lobe. the location and number of labeled peduncle lobe cells depended on the extent of the injection site in the optic lobe. | 1981 | 6167919 |
| pretectal neurons project to the salamander retina. | injection of horseradish peroxidase solution into the eye of some european salamander species labeled retrogradely pretectal neurons. these neurons lie near the commissura posterior and extend their dendrites into the visual pretectal neuropil. on the average, each animal contained 28 labeled cells. their distribution is bilaterally with a slight preference to the contralateral pretectum. as in other vertebrates these retrogradely labeled pretectal cells may be considered as efferents to the sal ... | 1981 | 6167917 |
| light microscopic analysis of contacts between pairs of identified leech neurons with combined use of horseradish peroxidase and lucifer yellow. | intracellular injections of horseradish peroxidase (hrp) and lucifer yellow (ly) were used to determine the locations of possible synaptic contacts between pairs of identified leech neurons. the pairs studied were ipsilateral touch sensory neurons (t cells), t cells plus the large longitudinal motoneuron (l cell), and t cells plus the annulus erector motoneuron (ae cell). the joint use of epi-fluorescence and transmitted light permitted the simultaneous observation of the processes of the hrp- a ... | 1981 | 7346573 |
| ultrastructure of identified fast excitatory, slow excitatory and inhibitory neuromuscular junctions in the locust. | the specialized jumping muscle of the locust, the metathoracic extensor tibiae (eti), is innervated by four physiologically different motoneurons, including feti, a phasic excitor, seti, a tonic excitor, and ci, a tonic common inhibitor. feti neuromuscular junctions were examined in three phasic eti bundles innervated by feti. feti terminals were characterized by patchy contacts on to granular sarcoplasm. the eti accessory extensor, innervated by both seti and ci, contains two morphologically di ... | 1981 | 7310457 |
| ultrastructure of migrating spinal motoneurons in anuran larvae. | motoneurons in the course of migration to the lateral motor column (lmc) were identified by horseradish peroxidase (hrp) applied to lumbar ventral roots in anuran larvae (rana catesbeiana). the ultrastructural characteristics of these migrating motoneurons were compared with motoneurons in the lmc that had completed their migration. both migrating and lmc motoneurons tended to be bipolar with one process extending toward the ependyma and the other out towards the ventral root. typically, central ... | 1981 | 6972797 |
| [inhibition and inactivation of horseradish peroxidase by thiourea]. | the kinetics of horseradish peroxidase (ec 1.11.1.7)-catalyzed oxidation of o-dianisidine by hydrogen peroxide in the presence of thiourea were studied. at the first, fast step of this process thiourea acts as a competitive reversible inhibitor with respect to o-dianisidine (ki = 0.22 mm). the formation of a thiourea-peroxidase complex was determined by the increase in the absorbance at a495 and a638 of the enzyme. the dissociation constant for the peroxidase-thiourea complex is equal to 2.0-2.7 ... | 1981 | 6789896 |
| projection of lateral line afferents in a teleost's brain. | after injection of horseradish peroxidase solution into the lateral line nerves of a poeciliid fish the afferent fibres can be followed up to their termination fields in the medulla, lobus vestibulolateralis, corpus cerebelli and valvula cerebelli. labelling of all fibres innervating individual neuromasts reveals a well-ordered branching pattern of afferents in the cns and a projection to all termination areas. | 1981 | 6167914 |
| the organization of thalamic projections to the parietal cortex of the virginia opossum. | the thalamic projections to somatic sensory-motor (ssm) cortex and adjacent cortical areas of the virginia opossum were studied using anterograde and retrograde axoplasmic transport techniques. large injections of horseradish peroxidase and/or tritiated amino acids were made in the parietal cortex to identify all of the thalamic nuclei that are interconnected with this large cortical area. very restricted injections were then made in physiologically identified subdivisions of ssm cortex, in the ... | 1981 | 7240450 |
| afferents to the midbrain auditory center in the bullfrog, rana catesbeiana. | horseradish peroxidase (hrp) histochemistry was used to visualize cells afferent to the bullfrog torus semicircularis. these afferent cells are located in several sensory and nonsensory nuclei. the sensory structures which project to the torus are mainly auditory nuclei, with the major input coming from the ipsilateral superior olive. a very small contralateral projection is also present. in addition, afferents arise from the contralateral, and to a lesser extent ipsilateral, dorsal acoustic nuc ... | 1981 | 6972387 |
| forebrain connections in the goldfish support telencephalic homologies with land vertebrates. | horseradish peroxidase injections into dorsomedial and dorsolateral regions of the goldfish (carassius auratus) telencephalon demonstrate, by retrograde cell labeling, that the teleost telencephalon receives a pattern of projections from the thalamus remarkably similar to those of land vertebrates. the evidence provides support for a homology between the dorsomedial region and the corpus striatum of land vertebrates and a homology between two dorsolateral regions and the dorsal and medial palliu ... | 1981 | 6971493 |
| a note on the reciprocal connections between the retina and the brain in the puffer fish tetraodon fluviatilis. | this investigation employed the horseradish peroxidase methodology to trace afferent and efferent connections of the retina in the puffer fish tetraodon fluviatilis. the retinal projections to the cns are within the range described in other teleost fishes. in addition to this observation, 4 structures were identified in the cns which project to the retina. these are the optic tectum, the dorsomedial optic nucleus, the pretectal nucleus and the large and well differentiated corpus geniculatum lat ... | 1981 | 7254695 |
| electrophysiological analysis of mitral cells in the isolated turtle olfactory bulb. | 1. an in vitro preparation of the turtle olfactory bulb has been developed. electrophysiological properties of mitral cells in the isolated bulb have been analysed with intracellular recordings. 2. mitral cells have been driven antidromically from the lateral olfactory tract, or activated directly by current injection. intracellular injections of horseradish peroxidase (hrp) show that turtle mitral cells have long secondary dendrites that extend up to 1800 micrometer from the cell body and reach ... | 1981 | 7310692 |
| habenular asymmetry and the central connections of the parietal eye of the lizard. | histochemical and autoradiographic analyses of the axonal transport of horseradish peroxidase and tritiated amino acids were employed to study the central connectivity of the lizard parietal eye. somata and processes of centrifugal fibers to the parietal eye were localized in tissue of the dorsal sac and in the leptomeningeal sheath of the pineal gland. analyses of series of transverse sections of the brain showed the left medial habenular nucleus to be subdivided into pars dorsolateralis and pa ... | 1981 | 7229138 |
| structural implication of the heme-linked ionization of horseradish peroxidase probed by the fe-histidine stretching raman line. | | 1981 | 7217068 |
| homotopic and heterotopic callosal afferents of caudal inferior parietal lobule in macaca mulatta. | we have examined callosal-axon neurons giving rise to homotopic and heterotopic callosal projections to caudal inferior parietal lobule (area pg) in macaca mulatta, identifying these neurons by means of retrograde axonal transport of horseradish peroxidase. the labeled neurons in the homotopic region occur predominantly in layers iiib and v.a moderate number are also seen in layer vi, a smaller number of layer iv, and rare cells occur in layer ii. these neurons occupy a region very similar in ou ... | 1981 | 7229130 |
| uptake of horseradish peroxidase by presynaptic terminals of bipolar cells and photoreceptors of the from retina. | the uptake of horseradish peroxidase (hrp) into synaptic vesicles of presynaptic terminals in the inner and outer plexiform layers of isolated frog retinas was studies by electron microscopy. uptake into the terminals of bipolar cells was found to be enhanced by exposure of the preparations to elevated concentrations of potassium ions, and by exposure to aspartic acid or glutamic acid. glycine had much less effect on the terminals. these results suggest that hrp uptake may prove useful in monito ... | 1981 | 6972957 |
| an anatomical and physiological study of regeneration of the eighth nerve in the leopard frog. | the ability of auditory fibers in the anuran's viiith nerve to regenerate back into the central nervous system after their axons have been served was studied electrophysiologically and anatomically. single unit recordings in the regenerated portion of the nerve indicate that: (1) fibers from both the amphibian and basilar papillae regenerate; (2) tuning curves of regenerated fibers, as in normal fibers, are 'v' shaped and retain their sharp frequency selectivity; (3) latency and threshold measur ... | 1981 | 6971688 |
| two visual pathways to the telencephalon in the nurse shark (ginglymostoma cirratum). ii. ascending thalamo-telencephalic connections. | as part of a study on retino-telencephalic pathways the ascending connections to the telencephalic central nucleus were investigated by retrograde transport of horseradish peroxidase. the central nucleus of the telencephalon, which is the main recipient for input from the brainstem, grossly can be divided into three rostrocaudal parts according to their afferent connections. the rostral third receives input mainly from the contralateral central thalamic nucleus and to a lesser degree from the la ... | 1981 | 7204670 |
| two visual pathways to the telencephalon in the nurse shark (ginglymostoma cirratum). i. retinal projections. | the central projections of the retina in the nurse shark were studied by anterograde transport of horseradish peroxidase and tritiated proline. with regard to efferent retinal fibers, both techniques gave completely identical results. projections were found to pretectal area, dorsal thalamus, basal optic nucleus, and optic tectum, all at the contralateral side. the retinal target cells in the dorsal thalamus are restricted to the ventrolateral optic nucleus and the posterior optic nucleus. no ev ... | 1981 | 7204669 |
| topographic and morphometric effects of bilateral embryonic eye removal on the optic tectum and nucleus isthmus of the leopard frog. | rana pipiens were raised through metamorphosis after extirpation of both eye primordia at shumway embryonic stage 17 (shumway '40). the visual connections between the isthmic nuclei and the optic tectum were examined in these animals using horseradish peroxidase (hrp) histochemistry. isthmo-tectal projections are normally aligned with the primary retinotectal map. we asked whether these connections would develop normal topographic organization in the absence of normal retinal input. hrp was form ... | 1981 | 6970759 |
| the aberrant retino-retinal projection during optic nerve regeneration in the frog. ii. anterograde labeling with horseradish peroxidase. | previous experiments have shown that a substantial number of regenerating optic axons in adult frogs (rana pipiens) are misrouted into the opposite optic nerve and retina during early stages of regeneration. this projection is maximal at 5 and 6 weeks after optic nerve crush. to further characterize this anomalous projection, small quantities of horseradish peroxidase (hrp) were injected into the right eye or right optic nerve 5 or 6 weeks after right optic nerve crush. twenty-four hours later t ... | 1981 | 6970757 |
| the aberrant retino-retinal projection during optic nerve regeneration in the frog. i. time course of formation and cells of origin. | we have reported previously that during optic nerve regeneration in rana pipiens, axons are misrouted into the opposite nerve and retina. in the present investigation we have examined the time course of formation of these "misrouted" axons and their cells of origin. the right eye of 31 frogs was injected with 3h-proline at various times after right optic nerve crush. in every frog examined 2 weeks and later after nerve crush, the distribution of autoradiographic label indicated that axons from t ... | 1981 | 6970756 |
| electron-nuclear double resonance of horseradish peroxidase compound i. detection of the porphyrin pi-cation radical. | electron-nuclear double resonance spectra of horseradish peroxidase compound i exhibit resonances from 14n and beta-protons, and most probably alpha-protons as well. the measurements prove that the oxyferryl iron of this enzymic intermediate is spin-coupled to a porphyrin radical. comparison of experimentally obtained average pi-electron spin densities with theoretical predictions for a 4-fold symmetric porphyrin pi-cation radical is supportive of a 2a2u assignment for the radical's electronic s ... | 1981 | 6257699 |
| transport across endodermal cells of the chick yolk sac during early stages of development. | the endoderm of the chick yolk sac mediates the transfer of materials from the yolk mass to the embryonic circulation. there is little evidence of endocytotic activity in the area pellucida, but the endodermal cells of the area vasculosa possess many microvilli and bristle-coated pits and vesicles, as well as a canalicular system and vacuoles in the apical cytoplasm. three tracers, horseradish peroxidase, ferritin, and latex spheres, were injected beneath the endoderm of both cultured embryos an ... | 1981 | 7223677 |
| channel gating at frog neuromuscular junctions formed by different cholinergic neurones. | 1. drug-induced membrane current fluctuations were analysed at frog ectopic neuromuscular junctions formed de novo by somatic motoneurones and by preganglionic autonomic neurones of the vagus nerve, and at denervated end-plates reinnervated by the vagus nerve. 2. at ectopic motor end-plates, the mean open time of the ion channels activated by ach is tau ach = 1.8 +/- 0.1 msec (s.e.) at -70 to -90 mv and 15-18 degrees c. carbachol- and suberyldicholine-induced channels have average open times tau ... | 1981 | 6267263 |
| isthmic afferent neurons identified by the retrograde hrp method in a teleost, navodon modestus. | isthmic afferent neurons were investigated by the retrograde horseradish peroxidase (hrp) method in a teleost, navodon modestus. following hrp injections into the nucleus isthmi, large pyriform neurons are labeled in the ipsilateral optic tectum. very large and multipolar neurons are also labeled in the ipsilateral nucleus pretectalis. no labeled neurons were found in other areas. | 1981 | 7470901 |
| an 'on the slide' modification of the de olmos-heimer horseradish peroxidase method. | the de olmos-heimer horseradish peroxidase method has been simplified without losing its sensitivity. the modification involves the use of cryostat sections and omitting several steps from the original procedure. the modification is especially suitable for small pieces of tissue that would otherwise require imbedding. | 1981 | 7219884 |
| evidence for a catecholaminergic projection to area x in the zebra finch. | in the zebra finch (poephila guttata), horseradish peroxidase injected into or near area x of the lobus parolfactorius (lpo) is transported to cell bodies in ipsilateral hyperstriatum ventrale pars caudale (hvc), area ventralis of tsai (avt), and nucleus tegmenti pedunculo-pontinus, pars compacta (tpc). area x, lpo, and paleostriatum augmentatum (pa) all contain a dense network of catacholamine-containing axons and nerve terminals, as determined in histofluorescence studies. cell bodies in avt a ... | 1981 | 7217361 |
| transneuronal labeling with horseradish peroxidase in the visual system of the house fly. | horseradish peroxidase (hrp) is taken up by lesioned neurons in the fly cns and passes from these into certain sets of adjoining neurons which are in synaptic contact. this transneuronal labeling resolves neurons in fine detail. electron microscopy shows reaction product in secondary neurons associated with plasmalemma and microtubules. in some cases also vesicles were found containing reaction product. it is suggested that the transneuronal passage takes place in vivo. | 1981 | 7011472 |
| retinotopic analysis of fiber pathways is amphibians. i. the adult newt cynops pyrrhogaster. | the possibility that pathways of retinal fibers within the optic tract and the tectum of the adult newt are retinotopic was examined by selective labeling of the retinal fibers with horseradish peroxidase. within the optic tract fibers from the ventral, temporal and dorsal retinal quadrants were ordered from the dorsal to ventral edges of th optic tract. the nasal retinal fibers exhibited two different pathways. the fibers from the dorsonasal retina ran along the ventral edge of the optic tract, ... | 1981 | 6162523 |
| retinotopic analysis of fiber pathways in the regenerating retinotectal system of the adult newt cynops pyrrhogaster. | retinotopic analysis of the pathways of regenerating retinal fibers within the optic tract and in the tectum of an adult newt was performed by selective labeling of the retinal fibers with horseradish peroxidase. at the tenth week of regeneration, all the regenerating retinal fibers from different retinal quadrants had terminal arbors nearly at the parts of the tectum innervated normally by those quadrants. the pathways for individual retinal fibers, however, were greatly disorganized within the ... | 1981 | 6162521 |
| synaptic regeneration and glial reactions in the transected spinal cord of the lamprey. | we have examined axonal growth and synaptic regeneration in identified giant neurons of the transected lamprey spinal cord using intracellular injection of horseradish peroxidase. wholemounts together with serial section light and electron microscopy, show that axons from identified müller and mauthner reticulospinal neurons grow across the lesion and regenerate new synaptic contacts. relatively normal swimming returns in these animals by 3-4 weeks after spinal transection. this occurs despite t ... | 1981 | 7310446 |
| a method for rapid filling of fine-tipped micropipettes with electrolyte solutions including those containing horseradish peroxidase. | cooling the tips of micropipettes pulled from filament-containing capillary glass dramatically increases the rate and completeness of filling with a variety of electrolyte solutions. in tests with solutions containing horseradish peroxidase this method increased the completeness of filling by more than two orders of magnitude. | 1981 | 7218853 |
| transformation of signals by interneurones in the barnacle's visual pathway. | 1. the photoreceptors of the median eye of the giant barnacle drive decrementally-conducting neurones in the supraoesophageal ganglion termed ;inverting cells' (i-cells) which in turn drive impulse-producing neurones termed ;amplifying cells' (a-cells). using intracellular recording techniques we have studied the role of i-cells in visual processing.2. horseradish peroxidase injections show that i-cells are interneurones whose processes are confined to the regions of the photoreceptor terminals ... | 1981 | 6267250 |
| cell death of motoneurons in the chick embryo spinal cord. v. evidence on the role of cell death and neuromuscular function in the formation of specific peripheral connections. | previous reports from this laboratory have shown that the chronic treatment of chick embryos with neuromuscular blocking agents (e.g., curare, alpha-bungarotoxin), during the period of naturally occurring cell death of spinal motoneurons (days 5 to 10), greatly reduces the amount of cell death in this system. the surviving motoneurons continue differentiation and innervate the peripheral musculature. since cell death has been prevented in these preparations from the earliest stages of limb inner ... | 1981 | 6167691 |
| temperature dependent rise in activity of horseradish peroxidase caused by non-ionic detergents and its use in enzyme-immunoassay. | non-ionic detergents such as polyoxyethylene-octylphenol or -sorbitolester were found to increase activity of horseradish peroxidase due to delay of inactivation in the course of substrate reaction. this rise in activity was investigated using different chromogens and was highest with o-dianisidine. an increasing stability of the enzyme to higher reaction temperatures was observed when detergents were added to the substrate solution, and the action of detergents also is enhanced with increasing ... | 1981 | 7008984 |
| tectal projections of an infrared sensitive snake, crotalus viridis. | crotaline snakes have detectors for infrared radiation and this information is projected to the optic tectum in a spatiotopic manner. the tectal projections were examined in crotalus viridis with the use of silver methods for degenerating fibers and the autoradiographic and horseradish peroxidase tracing methods. large lesions included all of the tectal layers but not the underlying structures. projections to the thalamus include a sparse input to the ipsilateral ventral and dorsal lateral genic ... | 1981 | 7204658 |
| central distribution of octavolateral afferents and efferents in a teleost (mormyridae). | the central distribution of afferents from individual eight nerve branches (n viii) and mechanical lateral line end organs in mormyrid fish are described. afferents were labeled with horseradish peroxidase (hrp) placed on the cut ends of the different n viii branches and the anterior and posterior lateral line nerves. descending, tangential, and magnocellular nuclei receive input almost exclusively from the utriculus and canals. nucleus octavius receives afferents from the lateral line nerves an ... | 1981 | 7204654 |
| proton nuclear magnetic resonance investigation of the electronic structure of compound i of horseradish peroxidase. | | 1981 | 7451437 |
| displaced ganglion cells and the accessory optic system of pigeon. | the central projection and retinal distribution of displace ganglion cells (dgc's) are described for the pigeon. discrete, localized injections of horseradish peroxidase (hrp) into the nucleus of the basal optic root (nbor) complex labeled as many as 4,800 dgc's in the contralateral retina. the greatest densities of dgc's were observed in the more peripheral regions of the middle and inferior temporal regions of the retina, with lowest densities occurring in the inferior nasal, red field, and fo ... | 1981 | 7251927 |
| development of blood-cerebrospinal fluid barrier to horseradish peroxidase in the avian choroidal epithelium. | the penetration of horseradish peroxidase (hrp) from blood into ventricle via the avian choroid plexus was examined by electron microscopy in order to study the development of the blood-cerebrospinal fluid barrier (bcsfb). 1-20 mg hrp was injected into the allantoic vein of chick embryos between the 7th and 21st day of incubation. until the 8th day (stage 34) the reaction products of injected hrp were observed in the interepithelial clefts at both luminal (ventricular) and abluminal sides. at th ... | 1981 | 7471179 |
| early development of postganglionic sympathetic trunk neurons in the chick embryo. | the main object of this investigation was to determine at which embryonic age the axonal endings of the first outgrowing sympathetic trunk neurons reach the shank musculature of the chick embryo. horseradish peroxidase was injected in the shank musculature at different embryonic ages. labelling of the sympathetic trunk perikarya was considered as evidence for the presence of sympathetic axonal endings in the injected area of the shank musculature. the earliest labellings were found at 8 days of ... | 1981 | 7331757 |
| on the question of the ventral intermediate nucleus in primate thalamus. a study of the lesser bushbaby, galago senegalensis. | cytoarchitectural and hodological evidence is given which supports the contention that the large-celled, intermediate zone between ventral posterior lateral (vpl) and ventral lateral (vl) nuclei is an independent thalamic nucleus, designated as the ventral intermediate nucleus (vim), in the thalamic ventral tier of galago senegalensis. observation of nissl-stained sections indicates that vim contains cells which are larger than those in vl and more scattered in appearance than those in vpl. fink ... | 1981 | 7326571 |
| telencephalic efferents in channel catfish, ictalurus punctatus: projections to the olfactory bulb and optic tectum. | telencephalic projections to the olfactory bulb and optic tectum were examined with horseradish peroxidase (hrp) methods in catfish. olfactory bulb afferents arise from the mitral cell layer of the contralateral olfactory bulb and the ipsilateral telencephalon. the majority of labelled cells appear within the ventral and dorsal nuclei of area ventralis telencephali and two divisions of the central zone of area dorsalis telencephali. excepting one division of the dorsal central zone, all afferent ... | 1981 | 7326567 |
| [the origin of efferent fibers to the inner ear on reptiles. a hrp study in caiman crocodilus (author's transl)]. | the origin of efferent fibers to the inner ear was studied in caiman crocodilus. after injection of horseradish peroxidase into the basilar papilla or into the ampullae of the horizontal and anterior semicircular canals, neurons labeled by the granular reaction product of retrogradely transported hrp were found in the medulla oblongata bilaterally. parent cells of the efferent cochlear bundle were found in the medial reticular nucleus and in the rostroventral division of the superior olive bilat ... | 1981 | 7316872 |
| morphology of migrating trigeminal motor neuroblasts as revealed by horseradish peroxidase retrograde labeling techniques. | | 1981 | 7301120 |
| morphological changes in cultured myotubes treated with agents that interfere with lysosomal function. | treatment of cultured muscle cells with the inhibitors of lysosomal function, leupeptin, and chloroquine, decrease the degradation of acetylcholine receptors (achr) and causes accumulation of undegraded receptors intracellularly. under these conditions the number of cytoplasmic coated vesicles, i.e. structures that appear to transport this receptor within the cultured muscle cell, increases in parallel. this study investigates the effects of leupeptin and chloroquine on the morphology of culture ... | 1981 | 7296646 |
| development of retinofugal neuropil areas in the brain of the alpine newt, triturus alpestris. | the development of the retinofugal projection areas of the brain has been studied in larvae of triturus alpestris by means of anterograde transported horseradish peroxidase. the optic tract establishes contacts with the optic tectum prior to the onset of robust terminal formation in the diencephalon. the tectum becomes covered by the retinofugal projection in a rostro-caudal direction. the basal optic neuropil develops synchronously with the oculomotor neurons. their dendrites extend into this n ... | 1981 | 7283179 |
| basal ganglia projections to the brain stem in the lizard varanus exanthematicus as demonstrated by retrograde transport of horseradish peroxidase. | | 1981 | 7266879 |
| laminar organization of efferent cells in the parietal cortex of the virginia opossum. | the size, shape and laminar position of efferent neurons in the parietal cortex of the virginia opossum were identified using the method of retrograde transport of horseradish peroxidase (hrp). injection of hrp into the spinal cord, dorsal column nuclei or pontine nuclei leads to labeling of cells in layer v and occasionally in layer vi, while a large injection of hrp in the dorsal thalamus labels many cells in layer vi, with fewer cells in layer v. hrp injections in the ssm cortex label cells i ... | 1981 | 7262228 |
| compressed retinotectal projection in hamsters: fewer ganglion cells project to tectum after neonatal tectal lesions. | after partial ablation of the superior colliculus (tectum) in neonatal hamsters, the whole extent of the visual field comes to be represented in a compressed map on the remaining tectal fragment. however, the total volume of tectal tissue in which retinotectal fibers arborize is less than normal. these observations suggests that the retinal ganglion cells which arborize in this reduced volume might arise throughout the whole extent of the retina but be fewer in number than normal. alternatively, ... | 1981 | 7262223 |
| the pattern of lateral-line afferents in urodeles. a horseradish-peroxidase study. | the organization of posterior and anterior afferents of the lateral-line system was studied in several species of urodeles by means of transganglionic transport of horseradish peroxidase. the afferents of each lateral-line nerve form distinct fascicles in the medullary alar plate. each of the two branches of the anterior lateral-line nerve is organized in two long and one short fascicles. the posterior lateral-line afferents form only two long fascicles. each ordinary neuromast is supplied by on ... | 1981 | 7261043 |
| retinofugal and retinopetal connections in the upside-down catfish (synodontis nigriventris). | the retinofugal and retinopetal connections in the upside-down catfish synodontis nigriventris were studied by use of the horseradish-peroxidase (hrp) techniques, autoradiography, and degeneration-silver methods. an unusual retinal projection to the torus semicircularis as well as projections to the retina from three different sources in the brain are described. after intra-ocular injections of hrp, labeled cells were found in the optic tectum, the dorsomedial optic nucleus and one of the pretec ... | 1981 | 7261035 |
| organization of thalamic projections to visual cortex in opossum. | projections from visual thalamus to posterior cortex of the virginia opossum revealed by retrograde transport of horseradish peroxidase show a specific and orderly pattern. the lateral geniculate nucleus projects only to cortical area 17, while a lateral sector of the lateral posterior nucleus sends afferents both to area 17 and 18. area 19 receives input from the lateral intermediate nucleus; the caudomedial sector of the lateral posterior nucleus projects to the anterior and posterolateral are ... | 1981 | 7237104 |
| connections of the olfactory bulb in the piranha (serrasalmus nattereri). | the connections of the olfactory bulb were studied in the piranha using the nauta and horseradish-peroxidase methods. three olfactory tracts project to seven terminal fields in the telencephalon and one in the diencephalon, all of them bilaterally. the contralateral olfactory bulb also receives a small input. all contralateral projections decussate in the anterior commissure and are relatively weak compared to the ipsilateral projections. hrp-containing cells were found in all of the ipsilateral ... | 1981 | 7226204 |
| the development of the stomach in clarias lazera and the intestinal absorption of protein macromolecules. | the development of the stomach of the teleost, clarias lazera, during the early posthatching period, is described, and the developing stomach is compared with that of adult clarias. the stomach develops in two distinct parts: the corpus, which differentiates first, and the pylorus. the corpus contains a mucous surface epithelium, arranged in folds, and a tubular gland system containing only one type of gland cell, to which the secretion of pepsinogen and hcl is attributed. the pyloric region doe ... | 1981 | 7214483 |
| input and output synapses on identified motor neurones of a locust revealed by the intracellular injection of horseradish peroxidase. | physiologically characterised motor neurones in the thoracic ganglia of the locus were injected with horseradish peroxidase in order that the spatial relationship between their input and output synapses could be observed with the electron microscope. a modification in the development procedure for the peroxidase ensured that the internal fine structure of the stained neurones was not obscured by the diaminobenzidine reaction product. input and output synapses may occur within 1 micrometer of eac ... | 1981 | 7214479 |
| identification and morphometric evaluation of the synapses of optic nerve afferents in the optic tectum of the axolotl (ambystoma mexicanum). | ther terminals of retinal afferents in the tectum of the axolotl have been identified ultrastructurally using techniques of horseradish peroxidase-filling and degeneration. the mitochondria in filled structures show a characteristic electron-lucent matrix. after both eyes have been removed, terminals with light mitochondria disappear from the area known to receive an optic input. in this area the presence of light mitochondria is almost always diagnostic of the retinal origin of a bouton. the sy ... | 1981 | 7214469 |
| inputs to the torus semicircularis in the electric fish eigenmannia virescens. a horseradish-peroxidase study. | the posterior lateral-line lobe, contrary to present belief, projects bilaterally to the torus semicircularis, although the contralateral projection is considerably more extensive. the torus also receives bilateral inputs from the medial octavo-lateralis nuclear complex, the reticular formation, a sublemniscal nucleus, and the nucleus prae-eminentialis. unilateral inputs to the torus were found originating from the ipsilateral mesencephalic tectum and the contralateral lobus caudalis of the cere ... | 1981 | 7194147 |
| a sensitive, specific, solid-phase enzymeimmunoassay for plasma progesterone. | a homologous enzymeimmunoassay (eia) for plasma progesterone, using a horseradish peroxidase conjugate as enzyme label and an antiserum raised against a progesterone-11 kappa-hemisuccinyl/bsa conjugate, is described. the antiserum was covalently linked to microcrystalline cellulose to facilitate separation of bound and free steroid; this solid-phase antiserum was stable for at least nine months when stored at 4 degrees c. the freeze-dried enzyme label is also stable, having retained both enzymic ... | 1981 | 7020564 |
| nurse cell-oocyte interaction in the telotrophic ovarioles of an insect, rhodnius prolixus. | microinjection of intracellular tracers fluorescein, procion yellow, lucifer yellow and horseradish peroxidase unequivocally showed the syncytial structure of the tropharium and its interaction with the oocytes. the tropharium tip is a separate isolated compartment. finger-like nurse cell projections comprising the syncytial tropharium interact via gap junctions along their abutting membranes and also via large cytoplasmic continuities at the central trophic core. the trophic cords connecting th ... | 1981 | 7013152 |
| absorption of protein molecules by the small intestine of the bullfrog tadpole, rana catesbeiana. | in the tadpole of the bullfrog, rana catesbeiana, the absorptive cells of the small intestine are characterized by the presence of invaginations of the surface plasma membrane or pinocytic vesicles in the apical cytoplasm and numerous lysosomes in the supranuclear region. these cytological features suggest that the absorptive cells may be able to ingest some macromolecules or particles. the possibility of macromolecular absorption in this animal was examined by using horseradish peroxidase (hrp) ... | 1981 | 6971913 |
| spinal projections from the mesencephalon in the toad. | mesencephalic cell groups projecting to the spinal cord have been identified by means of the retrograde axonal transport of the enzyme horseradish peroxidase (hrp). the injections were made either in the cervical or lumbar enlargements of the toad spinal cord. following injections in the cervical cord, labeled cells are located in the isthmus region, in the ipsilateral laminated nucleus posteroventralis tegmenti mesencephali (potter). at more rostral levels the labeled cells are in the nucleus o ... | 1981 | 6799147 |
| control of the pars intermedia of the lizard, anolis carolinensis. v. extravascular transfer and cellular uptake of horseradish peroxidase in the neuro-intermediate lobe. | the distribution of the tracer substance horseradish peroxidase (hrp, mw 40,000) in the neuro-intermediate lobe of the lizard, anolis carolinensis, was studied at various time intervals (13 min to 24 h) after vascular injection. hrp rapidly entered the extracellular lumen of the neural lobe, but did not penetrate into the third ventricle. the tracer was found in micropinocytotic vesicles (mpvs) of ependymal cells within 13 min after injection. the number of cellular inclusions containing hrp inc ... | 1981 | 6258794 |
| physiological and anatomical characteristics of primary vestibular afferent neurons in the bullfrog. | intracellular recordings were made in the viiith nerve of the bullfrog (rana catesbiana) to measure the membrane characteristics and obtain records of spontaneous and evoked spike activity of primary semicircular canal afferents. physiological stimulation of the canals was achieved by rotating the preparation on a servomotor driven turntable with the animals' head centered in the rotational axis. the responses of each neuron to sinusoidal rotations at frequencies of 0.05hz, 0.5hz and for impulsi ... | 1981 | 6172398 |
| nervous connections of the parietal eye in adult lacerta s. sicula rafinesque as demonstrated by anterograde and retrograde transport of horseradish peroxidase. | subsequent to the injection of horseradish peroxidase into the parietal eye of adult lacerta sicula, the course of the parietal nerve and its projections were determined. the parietal nerve enters the left habenular ganglion where it branches into a medial and a lateral route. some nerve fibers decussate within the habenular commissure. whereas this pathway exhibits a striking asymmetry at the level of the habenular ganglia, its projections to the dorsolateral nucleus of the thalamus, the perive ... | 1981 | 6168382 |
| interneuronal transfer of horseradish peroxidase associated with exo/endocytotic activity on adjacent membranes. | transneuronal transport of horseradish peroxidase (hrp) was observed by electron microscopy following intracellular injection of the enzyme into single interneurons inhibiting the teleost mauthner cell. complex membrane infolding, associating protrusions of the stained cells with adjacent indentations of the postsynaptic neuron, favours the interpretation that transport of hrp is brought about by an active process of extrusion and consecutive micropinocytosis of hrp by the target cell. | 1981 | 6166494 |
| hypophysiotropic neurons in the goldfish hypothalamus demonstrated by retrograde transport of horseradish peroxidase. | the horseradish-peroxidase (hrp) technique was used to visualize the cell bodies of axons projecting to the goldfish pituitary. following intravenous injections of hrp, hrp reaction products were observed in axons of the rostral pars distalis, proximal pars distalis, neurointermediate lobe, pituitary stalk and in axons coursing from the pituitary into the hypothalamus. hrp-labelled cells in the brain were localized in two regions only - the nucleus preopticus (npo) pars magnocellularis and pars ... | 1981 | 6166382 |
| central connections of the posterior lateral line lobe in mormyrid fish. | primary electroreceptor afferents terminate in the posterior lateral line lobe (plll) in electroreceptive teleosts. this paper examines the central connections of plll in fish of the family mormyridae using horseradish peroxidase and tritiated amino acid tracing techniques. some connections of the closely related lobus caudalis of the cerebellum are also examined. there are three zones on each side of the mormyrid plll cortex. two receive input from mormyromast receptors, and one from ampullary ... | 1981 | 6163655 |
| isolation of a heme crevice peptide from affinity-labeled horseradish peroxidase. | | 1980 | 7470149 |
| magnetic circular dichroism on oxygen complexes of hemoproteins: correlation between magnetic circular dichroism magnitude and electronic structures of oxygen complexes. | magnetic circular dichroism (mcd) and natural circular dichroism (cd) spectra are reported for horseradish peroxidase compounds ii and iii, and kangaroo myoglobin compound ii at ph values of 8.5 and 4.9. these compounds exhibited mcd spectra of apparent faraday a term both in the soret and q regions, except for myoglobin compounds in the soret region where intrinsic temperature dependence showed large contribution from faraday c terms. comparison of these data with the mcd spectra of the dioxyge ... | 1980 | 7213647 |
| formation of porphyrin pi cation radical in zinc-substituted horseradish peroxidase. | zinc-substituted horseradish peroxidase is oxidized by k2ircl6 to a characteristic state which retains one oxidizing equivalent more than the zinc peroxidase. the oxidized enzyme gives an optical absorption spectrum similar to that of compound i of peroxidase and catalase, and a g = 2 electron paramagnetic resonance signal which has an intensity corresponding to the porphyrin content. it is reduced back to the zinc peroxidase by a stoichiometric amount of ferrocyanide or by a large excess of k3i ... | 1980 | 6257291 |
| pathways involved in fluid phase and adsorptive endocytosis in neuroblastoma. | the endocytosis of ricin, horseradish peroxidase (hrp), and a conjugate of ricin-hrp by monolayer cultures of murine neuroblastoma was studied using morphological and biochemical techniques. the binding of (125)i-ricin and (125)i-ricin-hrp to cells at 4 degrees c, as a function of ligand concentration, was a saturable process. the apparent affinity constants, determined at equilibrium, were 2.8 x 10(6) m(-1) for ricin and 1 x 10(6) m(-1) for ricin-hrp. the number of binding sites per cell was 8 ... | 1980 | 7462317 |
| evaluation of screening tests for colorectal cancer. | the following guidelines are proposed for the asymptomatic patient representing for routine examination. instruct the patient to eat all bran cereal or a similar product for breakfast for three consecutive days prior to the day of appointment. at the time of appointment the stool obtained from rectal examination or from a spontaneous bowel movement is checked for occult blood using the guaiac method. if the findings are negative, no further tests are recommended. if positive, the patient is give ... | 1980 | 7010404 |
| a simple staining method for blood vessels in flat preparations of ocular tissues. | we describe a technique for light microscopic visualization of the vasculature of the retina, choroid, ciliary body, and iris in flat preparations. the technique is based on the intravenous injection of horseradish peroxidase, the histochemical demonstration of this enzyme's activity, and the bleaching of the melanin that hinders the visualization of the injected vessels. this technique is reproducible and much simpler than other available methods in which dyes suspended in different media are i ... | 1980 | 7002859 |
| enzyme immunoassay of estriol in pregnancy urine. | we describe an enzyme immunoassay for determination of total estriol in urine. estriol covalently bound to horseradish peroxidase is used as tracer, and free and bound hormone are separated by precipitation with polyethylene glycol. the method can be used with either acid hydrolysis at 100 degrees c for 30 min or enzyme hydrolysis at 50 degrees c for 40 min; results by the former procedure are about 15% lower than results by the latter. results were practically identical when we compared the enz ... | 1980 | 7002365 |
| dissociation of intracellular lysosomal rupture from the cell death caused by silica. | the relationship between intracellular lysosomal rupture and cell death caused by silica was studied in p388d(1) macrophages. after 3 h of exposure to 150 mug silica in medium containing 1.8 mm ca(2+), 60 percent of the cells were unable to exclude trypan blue. in the absence of extracellular ca(2+), however, all of the cells remained viable. phagocytosis of silica particles occurred to the same extent in the presence or absence of ca(2+). the percentage of p388d(1) cells killed by silica depend ... | 1980 | 6161936 |
| a kinetic study on the diffusion-coupled reaction of a basic horseradish peroxidase adsorbed on the carboxymethylcellulose membrane. | the rate of reactions of a basic horseradish peroxidase adsorbed on the carboxymethylcellulose membrane was measured spectrophotometrically by monitoring the state of the enzyme. for the reactions with hydrogen peroxide and cyanide dissolved in media the diffusion process was rate limiting both in the static and flowing media, and kinetic features of the enzyme were masked. the rate of co recombination of the ferrous enzyme was measured by flash photolysis in the static media containing varying ... | 1980 | 7430151 |
| neonatal enucleation induces an asymmetric pattern of visual callosal connections in hamsters. | autoradiography and the horseradish peroxidase (hrp) technique were used to investigate visual callosal connections in normal hamsters and in animals which had one eye removed at birth. in normals and in the cortex contralateral to the remaining eye in the neonatal enucleates, callosal cells and terminal labeling were restricted to the region around the area 17-18a border. in the cortex ipsilateral to the remaining eye in the neonatal enucleates labeled cells and terminal labeling were observed ... | 1980 | 7427734 |
| fourier-transformed infrared photoacoustic spectroscopy of biological materials. | a new technique for measuring the infrared spectra of solids has been developed. the photoacoustic spectra of hemin, hemoglobin, protoporphyrin ix, and horseradish peroxidase show how this technique can be used to obtain structural information about biological materials which cannot readily be studied by normal transmission infrared spectroscopy. the method requires milligram quantities of material and involves no sample preparation. | 1980 | 7434007 |
| new fluorogenic substrates for horseradish peroxidase: rapid and sensitive assays for hydrogen peroxide and the peroxidase. | | 1980 | 7469007 |
| excited indole-3-aldehyde from the peroxidase-catalyzed aerobic oxidation of indole-3-acetic acid. reaction with and energy transfer to transfer ribonucleic acid. | the horseradish peroxidase catalyzed aerobic oxidation of the auxin indole-3-acetic acid generates triplet indole-3-aldehyde in high yield. the excited species is quenched by oxygen with formation of singlet oxygen, which is responsible for the observed photon emission and can be trapped by suitable agents. trna dramatically enhances the emission as a result of energy transfer from triplet indole-3-aldehyde to a 4-thiouridine group in trna. triplet indole-3-aldehyde also adds covalently to trna. ... | 1980 | 7448169 |
| inhibition by catalase of dark-mediated glucose-6-phosphate dehydrogenase activation in pea chloroplasts. | dark activation of light-inactivated glucose-6-phosphate dehydrogenase was inhibited by catalase in a broken pea chloroplast system. partially purified glucose-6-phosphate dehydrogenase from pea leaf chloroplasts can be inactivated in vitro by dithiothreitol and thioredoxin and reactivated by h(2)o(2). the in vitro activation by h(2)o(2) was not enhanced by horseradish peroxidase, and dark activation in the broken chloroplast system was only slightly inhibited by nacn. these results indicate tha ... | 1980 | 16661532 |
| opposite effects of thiocyanate on tyrosine iodination and thyroid hormone synthesis. | the effect of a pseudohalide, scn-, an anion with the same molecular size as iodide, was studied on two reactions: thyroglobulin iodination and thyroid hormone synthesis (coupling reaction) catalyzed by peroxidases. the coupling reaction was studied separately from the iodination reaction by using labelled thyroglobulin samples previously iodinated but containing little or no hormones. 1. scn- inhibits iodide oxidation (i- leads to i2) whatever the enzyme, thyroid, lactoperoxidase or horseradish ... | 1980 | 7449758 |
| horseradish peroxidase. xlii. oxidations of l-tyrosine and 3,5-diiodo-l-tyrosine by compound ii. | the oxidations of both l-tyrosine and 3,5-diiodo-l-tyrosine by compound ii of horseradish peroxidase were studied over the ph range of approximately 5 to 10 at 25 degrees c and at a constant ionic strength of 0.11. the rate versus ph profile for the tyrosine - compound ii reaction illustrates the influences of at least two acid group ionizations. an enzyme dissociation (pka approximately 6.2) has a small effect on the reaction rate; whereas, a second pka of 9.2, which may be attributed to either ... | 1980 | 7214195 |
| effect of hypertension on blood-brain barrier. change after restoration of blood flow in post-ischemic gerbil brains. an electronmicroscopic study. | the effect of induced hypertension on the blood-brain barrier (bbb) change in mongolian gerbils exposed to various periods of ischemia was studied. evans blue dye was used to determine the bbb change in animals subjected to different levels of hypertension after 3 h ischemia. horseradish peroxidase (hrp) was used in electronmicroscopic studies of animals subjected to 30 min, 1, 3 or 6 h ischemia and subsequently exposed for 30 min to varying periods and sequences of normo- and hypertension. furt ... | 2016 | 7210066 |
| binding mode of indole to horseradish peroxidase. | | 1980 | 7447455 |
| propriospinal fibers interconnecting the spinal enlargements in some quadrupedal reptiles. | the cells of origin, course and site of termination of long propriospinal fibers interconnecting the intumescences have been studied with the aid of the horseradish peroxidase technique, as well as with anterograde degeneration techniques, in some quadrupedal reptiles (the lizards tupinambis nigropunctatus and varanus exanthematicus, and the turtles testudo hermanni and pseudemys scripta elegans). the anterograde degeneration findings suggest that long descending propriospinal fibers from the ce ... | 1980 | 6933169 |
| visualization of satellite cells in living muscle fibres of the frog. | satellite cells were visualized in living muscle fibres of the frog. single fibres or bundles consisting of a few fibres were isolated after treatment with collagenase, and viewed under the light microscope. subsequent electron microscopy of identified cells confirmed that they were satellite muscle cells. under the light microscope, satellite cells appear as fusiform cells, tapering into long fine processes usually orientated parallel to the muscle fibre axis. horseradish peroxidase injected in ... | 1980 | 6107923 |
| membrane recycling and endocytosis in paramecium confirmed by horseradish peroxidase pulse-chase studies. | paramecium caudatum cells were pulse-chased in horseradish peroxidase (hrp) using pulses of 30 s to follow endosome (endocytotic vesicle) formation from defaecating digestive vacuoles and 3-min pulses to follow the movement and fate of these vesicles in the cell. endosomes formed during the 30 s in hrp are heavily labelled with hrp reaction product and are mostly flattened. some align along microtubules that point toward the cytopharynx. diskoidal vesicles at the cytopharynx are unlabelled in un ... | 1980 | 7462342 |
| action of prostaglandin e1 and f2 alpha on the pinocytic activity of horseradish peroxidase in bone-marrow derived macrophages. | the influence of prostaglandin e1 and f2 alpha on the pinocytic activity of bone-marrow macrophages was studied biochemically and morphometrically. the results show that prostaglandin e1 induces 44% inhibition of pinocytosis of horseradish peroxidase; prostaglandin f2 alpha has no significant effect. morphometrical analysis of electron micrographs demonstrates that inhibition of pinocytosis is connected with diminished average size and raised number of pinocytic vesicles. the influence of prosta ... | 1980 | 7449778 |
| anatomic pathway of fluid leakage in fluid-overload pulmonary edema in mice. | mice were given an intravenous injection of isotonic saline containing horseradish peroxidase (hrp) as an ultrastructural marker in an attempt to determine the site of fluid leakage from the vascular space to the air space in the lung. the localization of hrp was studied by ultrastructural histochemistry. when injected in a small volume of saline (0.1 ml), hrp was confined in the vascular space. when the volume of saline was increased to 1.0 ml, the reaction product of hrp was found first in the ... | 1980 | 7446703 |
| relationships of the visual cortex in the marsupial brush-tailed possum, trichosurus vulpecula, a horseradish peroxidase and autoradiographic study. | the ascending and descending relationships of visual cortex in trichosurus were determined using hrp and autoradiographic methods. the visual thalamus, lgnd and lp, was found to project to three cytoarchitecturally distinct areas of cortex with each of these regions displaying differing patterns of connectivity with other centres. the striate and peristriate cortices received homotypically organized projections from lgnd as well as projections from both divisions of lp. the posterior parietal co ... | 1980 | 7216909 |
| ca2+-dependent recycling of synaptic vesicles at the frog neuromuscular junction. | frog cutaneous pectoris muscles were treated with low doses of crude black widow spider venom (bwsv) or purified alpha-latrotoxin, and neuromuscular transmission, quantal secretion, changes in ultrastructure and uptake of horseradish peroxidase (hrp) were studied. when these agents were applied to muscles bathed in a ca2+-free solution with 1 mm egta and 4 mm mg2+, the rate of quantal secretion rose to high levels but quickly subsided; neuromuscular transmission was totally and irreversibly bloc ... | 1980 | 6252215 |
| uptake, intra-axonal transport and fate of horseradish peroxidase in embryonic spinal neurons of the chick. | horseradish peroxidase (hrp) was injected in ovo into the ventral muscle mass of the hind limb of 5- to 7-day-old chick embryos or into the gastrocnemius muscle of 8- to 18-day embryos and localized histochemically. hrp is extensively incorporated via endocytosis into axonal growth cones or presynaptic terminals in the proximity of the injection site. much of the tracer is taken up in vesicles and small vacuoles. most of these are smooth-surfaced and only a few are bristle-coated. a small amount ... | 1980 | 6160167 |
| vesicular transport of horseradish peroxidase by ependymal cells of the medulla oblongata. | | 1980 | 6156741 |
| a histochemical model dealing with an immobilized glucose oxidase-peroxidase system. the influence of diffusion limitations on histochemical results. | a histochemical model dealing with an immobilized bienzyme system (glucose oxidase-peroxidase) is presented. the model is an artificial proteic membrane obtained by a previously described co-cross-linking process. the kinetic properties of free and immobilized horseradish peroxidase were studied when 3,3'-diaminobenzidine is used as a hydrogen donor substrate. a new direct method was developed for immobilized enzyme activity measurements. computer simulation based on experimental kinetic paramet ... | 1980 | 7410817 |
| basal lamina thickness permeability to horseradish peroxidase of intraneural capillaries in diabetic mice. | | 1980 | 6253768 |
| the morphology of neurosecretory neurones in the pond snail, lymnaea stagnalis, by the injection of procion yellow and horseradish peroxidase. | | 1980 | 6107940 |
| a new tectal afferent nucleus of the infrared sensory system in the medulla oblongata of crotaline snakes. | the existence of an infrared sensory neuron group with ascending fibers which directly reach the optic tectum in crotaline snakes was confirmed with three methods. (1) with the retrograde horseradish peroxidase (hrp) method, labeled neurons were not found within the nucleus descendens lateralis nervi trigemini (dlv), but in an unnamed cell group located immediately ventral to the dlv of the contralateral side at the transitional portion between the nucleus oralis (dvo) and the nucleus interpolar ... | 1980 | 7397501 |