bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunohistochemical localization of enkephalin in the central nervous system and pituitary of the lizard, Anolis carolinensis
Authors: Naik Dhruba Raj , Sar Madhabananda , Stumpf Walter E. 
Published: May 2005

AbstractThe topographical distribution of enkephalin in the central nervous system of the lizard, Anolis carolinensis, has been studied by the immunoperoxidase technique with antiserum to leucine‐enkephalin. Immunoreactive enkephalin perikarya, fibers and probably terminals are widely distributed throughout the central nervous system, which agrees well with the distribution of enkephalins in the mammalian brain. Enkephalin‐containing perikarya are found in the subpallium (septum, nucleus accumbens, striatum, amydgala), preoptic and hypothalamic region, ventromedial nucleus and ventromedial area of thalamus, pretectal geniculate nucleus and posterodorsal nucleus of pretectum, nucleus of the lateral lemniscus, locus ceruleus, spinal trigeminal nucleus, nucleus of the solitary tract, medial parvocelluar nucleus, and dorsal horn of the spinal cord. Enkephalinergic fibers and terminals are found in the above–mentioned areas as well as in the pallium (medial and dorsal cortex, dorsal ventricular ridge), dorsomedial and anterior dorsolateral nucleus of the thalamus, habenua, nucleus of the stria medullaris, torus semicircularis, mesencephalic tegmental area, interpeducular nucleus, mesencephalic trigeminal nucleus, central gray, reticular formation, raphe nucleus, substantia nigra, isthmus region, and nucleus of the trapezoid body. Enkephalinergic pathways appear to exist between the septum and the medial cortex, nucleus accumbens and nucleus of the lateral olfactory tract, striatum and certain mesencephalic structures, hypothalamus and tegmentum, and between nucleus of the lateral lemniscus and torus semicirculais. In the pituitary, cells of the pars intermedia, and certain cells of the rostral pars distalis also show immunoreactivity to enkephalin antiserum. The distribution of enkephalin immunoreactivity throughout the hypothalamus and in the median eminence suggests involvement in neuroendocrine regulation. Presence of enkephalin in many extrahypothalamic brain areas indicates its important role in various sensory functions and in behavioral and autonomic integration.
Innervation and structure of extraocular muscles in the monkey in comparison to those of the cat
Authors: Spencer Robert F. , Porter John D. 
Published: May 2005

AbstractMotoneurones that innervate the medial rectus, lateral rectus, and accessory lateral rectus muscles in the monkey have been identified and localized by retrograde transport of horseradish peroxidase. Medial rectus motoneurones were located within both dorsal and ventral regions of the oculomotor nucleus, with a differential distribution along the rostral‐caudal axis of the nucleus. Lateral rectus motoneurones were located predominantly within the abducens nucleus, and were distributed throughout the rostral‐caudal extent of the nucleus. Motoneurones that innervate the accessory lateral rectus muscle comprised a group of large cells located approximately 0.5 mm ventral to the rostral protion of the abducens nucleus, corresponding to the ventral abducens nucleus of Tsuchida ('06). The ventral subgroup of abducens motoneurones, which innervate both the lateral rectus and accessory lateral rectus muscles, thus do not occupy a brain stem location similar to the cat accessory abducens nucleus, whose motoneurones innervate the retractor bulbi muscle, to which the accessory lateral rectus muscle presumably is homologous. A few accessory lateral rectus motoneurones also were located within the abducens nucleus, overlapping the distribution of lateral rectus motoneurones.Electron microscope examination of the lateral rectus muscle revealed the presence of three morphological types of singly innervated muscle fibers and two morphological types of multiply innervated muscle fibers that exhibited a differential distribution within the orbital, intermediate, and global regions of the muscle. The accessory lateral rectus muscle resembled the global portion of the lateral rectus muscle in containing two morphological types of singly innervated fibers and one type of multiply innervated fiber.These findings indicate that the central differences in the brainstem locations of motoneurones that innervate the cat retractor bulbi and monkey accessory lateral rectus muscles are correlated with peripheral differences not only in the morphology, but also possibly in the mechanical roles, of the muscles they innervate. The accessory lateral rectus muscle thus appears to have evolved both structurally and functionally towards more of a role in patterned eye movement. Furthermore, with the phylogenetic regression of the retractor bulbi muscle, the various types of eye movement with which this muscle is associated in lower vertebrates may be assumed by the other extraocular muscles in higher mammals, including humans.
The distribution of pontine projection cells in visual and association cortex of the cat: An experimental study with horseradish peroxidase
Authors: Albus K. , Donate‐Oliver F. , Sanides D. , Fries W. 
Published: May 2005

AbstractThe projections from the visual and association areas of the cat's neocortex to the pons were investigated with horseradish peroxidase as retrograde tracer. Small injections were made into the pars basalis of the pons, along its entire rostrocaudal extent. The cortical areas considered were areas 17, 18, 19, 20, 21, and the lateral suprasylvian areas (LSA); the posterior (PMSA), and the anterior middle suprasylvian association area (AMSA), the anterior lateral association area (ALA) and the anterior suprasylvian association area (ASA). A pontine projection was found for all the areas investigated; however, areas differ in the relative strength of their projection, in their intraareal distribution of projection cells, and in the location of their projection zones within the pons.A low to moderate density of projection cells is seen in the areas 17, 18, 19, 20, 21, and in PMSA. The posterior part of LSA contains only a few projection cells, whereas in more anterior parts of LSA the density of projection cells is moderate to high. A relatively dense distribution of projection cells also appears in AMSA, ALA, and ASA. In those areas which are retinotopically organized (17, 18, 19, LSA) the representation of the center of gaze contains far fewer projection cells than the representation of peripheral vision. In the association areas the distribution of projection cells appears even.The projection zones from areas 17, 18, and 19 overlap with the zones from LSA in the anterior half of the basal pons. The projection zones from areas 20 and 21 and from ALA and ASA are located in the middle third and the projection zones from PMSA and AMSA spread throughout the entire rostrocaudal extent of the basal pons.Our findings indicate that efferent impulses from the visual cortical areas and from the association areas on the middle suprasylvian gyrus are relayed to the cerebellum exclusively via the basal pontine nuclei. The findings further suggest that the visual corticopontine projections carry a map of the visual field in which the cortical magnification factor is reduced.
Onset of synapse formation in the human spinal cord
Authors: Okado Nobuo 
Published: May 2005

AbstractThe time of onset of synapse formation was examined in the cervical spinal cord of eight human embryos ranging from 4 (8 mm in crownrump length) to 6 (22 mm) weeks of ovulation age. The first synapses were found in the motor nucleus of a 10‐mm embryo (Streeter's horizon XV). They contained only a small number of synaptic vesicles and had asymmetrical membrane thickenings, with thicker postsynaptic membranes than presynaptic ones. With the exception of an occasional axosomatic synapse, nearly all synapses found in a 10‐mm embryo were axodendritic. In an 11‐mm embryo (Streeter's horizon XVI), synapselike contacts (SLC) were found in the dorsal marginal layer. They contained a small number of synaptic vesicles and had “reversed membrane specalization” with prominent presynaptic membrane densities. The number of SLC decreased in older embryos. Judging from the morphological characteristics of membrane specializations and the temporal decrease in number, SLC are considered to be either transient synapses on the borderline cells or axoglial synapses. Synapses in the regions outside the motor nucleus first appeared in the dorsal marginal layer of a 14‐mm embryo (Streeter's horizon XVII).
The olivocerebellar projection in the monkey. Experimental studies with the method of retrograde tracing of horseradish peroxidase
Authors: Brodal P. , Brodal A. 
Published: May 2005

AbstractFollowing injections of horseradish peroxidase (HRP) in various lobes and lobules of the macaque cerebellum the occurrence of retrogradely labeled cells in the inferior olive was mapped. Only cortical areas showing staining of the molecular layer were considered as sites of uptake of HRP. To facilitate comparisons between cases and presentation of findings, a diagram of the macaque inferior olive as imagined unfolded was constructed (Fig. 1). Attempts were made to compare the findings made with data on the olivocerebellar projection in the cat and the pattern of a longitudinal zonal subdivision of the cerebellum.In general there appears to be a remarkably close correspondence between the organization of the olivocerebellar projection in the monkey and the cat. The projection is precisely organized and appears to be purely crossed. Within the projections to some of the cerebellar cortical zones a topical pattern can be demonstrated.Olivary afferents to vermal lobules V, VII, and VIII are derived from the caudal half of the medial accessory olive, projecting to Voogd's zone A. The topical pattern resembles that in the cat (Fig. 8). After injections covering the lateral zone of the anterior lobe vermis (zone B), labeled cells are seen in the caudal part of the dorsal accessory olive. In some cases staining of the intermediate part of the anterior lobe and of the paramedian lobule is followed by labeling of cells in the rostral part of the dorsal accessory olive (zones C1 and C3) or in the rostral half of the medial accessory olive (zone C2). When the injected area covers lateral parts of the cerebellum, there is labeling in the principal olive (projecting to zones D1 and D2). Although not entirely decisive, the findings lend support to the view that the ventral lamella of the principal olive supplies zone D2, whereas the dorsal lamella supplies zone D1. The relatively sparse data in the literature on the afferents to the monkey olive are briefly considered. On many points the projections appear to be as in the cat. However, there is possibly a species difference between cat and monkey as concerns their receipt of afferents from the red nucleus.
The distribution of visceral primary afferents from the pelvic nerve to Lissauer's tract and the spinal gray matter and its relationship to the sacral parasympathetic nucleus
Authors: Morgan Charles , Nadelhaft Irving , de Groat William C. 
Published: May 2005

AbstractThe central distribution of visceral primary afferent fibers from the pelvic nerve of the cat and the relationship of these fibers to preganglionic neurons of the sacral parasympathetic neurons (SPN) have been studied. Horseradish peroxidase (HRP) applied to the cut pelvic nerve was detected ipsilaterally in preganglionic neurons and dorsal root ganglion cells (segments S1–S3), and in central afferent projections to Lissauer's tract (LT), the dorsal columns, the dorsolateral funiculus, and spinal gray matter. The afferent projections were strongest in the region of the SPN (S1–S3) but extended far beyond its limits (e.g., LT was labeled from L4 to Cx7). In the transverse plane, collateral fiber bundles formed a thin shell around the dorsal horn predominantly within lamina I and expanded into terminal fields in the gray matter. The more prominent lateral collateral projection (LCP) extended into laminae V and VI, whereas the medial one (MCP) ended in the dorsal commissure. In longitudinal planes these projections exhibited a periodicity with an interval of approximately 200 μm. The distribution of afferent collateral projections overlaps the regions where many preganglionic neurons and their dendritic extensions are located, and also areas known to contain interneurons involved in visceral pathways. A differential distribution of afferents within the SPN was noted where a higher intensity was observed in proximity to those neurons located in laminae V and VI, which innervate the colon, and a lower intensity near neurons located in lamina VII which innervate the bladder. This is consistent with the known spinal control of colon reflexes and the supraspinal control of bladder reflexes. The widespread rostrocaudal extent of the pelvic primary afferent projection is consistent with the necessity for the integration of somatic and autonomatic elements from various levels of the lumbo‐sacral‐coccygeal spinal cord in the performance of pelvic visceral functions.
Visual topography of V2 in the macaque
Authors: Gattass R. , Gross C. G. , Sandell J. H. 
Published: May 2005

AbstractThe representation of the visual field in the area adjacent to striate cortex was mapped with multiunit electrodes in the macaque. The animals were immobilized and anesthetized and in each animal 30 to 40 electrode penetrations were typically made over several recording sessions.This area, V2, contains a topographically organized representation of the contralateral visual field up to an eccentricity of at least 80°. The representation of the vertical meridian is adjacent to that in striate cortex (V1) and forms the posterior border of V2. The representation of the horizontal meridian in V2 forms the anterior border of V2 and is split so that the representation of the lower visual field is located dorsally and that of the upper field ventrally. As in V1, the representation of the central visual field is magnified relative to that of the periphery. The area of V2 is slightly smaller than that of V1. At a given eccentricity, receptive field size in V2 is larger than in V1.The myeloarchitecture of V2 is distinguishable from that of the surrounding cortex. The location of V2 corresponds, at least approximately, to that of cytoarchitectonic Area OB. V2 is bordered anteriorly by several other areas containing representations of the visual field.
Hypothalamic, other diencephalic, and telencephalic neurons that project to the dorsal midbrain
Authors: Morrell J. I. , Greenberger L. M. , Pfaff D. W. 
Published: May 2005

AbstractNeurons in the hypothalamus, other diencephalic regions, and the telencephalon which project to the mesencephalic central gray (CG) and the region lateral to it were demonstrated, in the rat, by the horseradish peroxidase retrograde neuroanatomical tracing method with diaminobenzidine and tetramethyl benzidine visualization reactions. The greatest concentrations of neurons that project to the dorsal mesencephalon were found in the ventromedial nucleus, particularly the anterior and ventrolateral subdivisions, in the dorsal premammillary nucleus, and in the zona incerta. Neurons that project to or lateral to the CG were also found in the laterocaudal hypothalamus, the dorsomedial hypothalamus, regions of the anterior hypothalamic area, specific areas of the cerebral cortex (32, 29, 8, 8A, 13, 14), and the central nucleus of the amygdala. Some neurons that project were also found in the preoptic area, septum, bed nucleus of the stria terminals, and the habenula.More neurons in the mediocaudal quadrant of the hypothalamus project to the mesencephalon than do those in laterocaudal, mediorostral, or laterorostral quadrants. More neurons in the medial than the lateral half, and more in the caudal than the rostral half of the hypothalamus project to the mesencephalon. More neurons project to the central gray, or the region lateral to it, at the inferior colliculus.These descending connections to the midbrain, particularly from the hypothalamus and zona incerta, are probably components of neural networks that regulate nociception, certain neuroendocrine functions, sexual and other behaviors, and certain autonomic functions.
Anatomical organization of primate visual cortex area VII
Authors: Lund J. S. , Hendrickson A. E. , Ogren M. P. , Tobin E. A. 
Published: May 2005

AbstractThe Golgi Rapid and Kopsch techniques have been used to provide material for an examination of the internal neuronal organization of cortical area VII of the Macaca monkey. The afferent and efferent relationships of area VII, as shown by axoplasmic transport tracing techniques in our own material and in previous studies in other laboratories, are reviewed. Comparison is made between the internal organisation of VI and VII cortex in terms of (1) the marked difference in spiny and nonspiny neuron populations of granular layer 4, (2) the difference in relationship of lamina 6 pyramidal neurons to the overlying layers with a shift away from any relationship to granular layer 4 in VII, and (3) differences in the organization of VI lamina 4B and VII lamina 3B—both similarly placed, fiber‐rich bands in the two cortical areas. The extrinsic relationships of VI and VII with the lateral geniculate nucleus, superior colliculus, pulvinar, peristriate cortex, cortical area STS, and with each other are compared in terms of laminar locations of efferent neurons and afferent axon terminal fields. It is hoped that this anatomical survey will provide a better foundation for physiological explorations of the region.
Changes in the length and organization of nucleus laminaris dendrites after unilateral otocyst ablation in chick embryos
Authors: Parks Thomas N. 
Published: May 2005

AbstractTo evaluate the contributions of the ear and acoustic stimulation to the structural development of central auditory neurons, the right otocyst was surgically destroyed in chick embryos on the third day of incubation. This pro‐cedure prevents the formation of the inner ear and acousticovestibular nerve and thus removes the dominant afferent synaptic input to nucleus magnocellularis (NM). Subsequently, nucleus laminaris (NL), which receives afferent synaptic input to its dorsal dendrites from the ipsilateral NM and afferents to its ventral dendrites from the contralateral NM, was studied on both sides of the brain in Golgi preparations. By embryonic day 17, the total lengths of the individual NL dendritic fields connected to the right NM (i.e., the manipulated dendrites) were decreased by an average of 44% as compared to those NL dendrites connected to the left NM (i.e., the unmanipulated dendrites). The mean length of the unman‐ipulated dendrites in experimental animals, however, did not differ from average dendritic length in normal control embryos. The amount of dendritic length lost by a NL neuron was strongly correlated with the length of the unmanipulated dendrites on the opposite side of the same neuron and with that neuron's position within NL. The lengths of dorsal and ventral dendrites on individual neurons were at least as highly correlated in experimental as in normal control animals. Correlation of dendrite length with the position of measured neurons within NL indicated that the large rostromedial‐to‐caudolateral gradient of increasing den‐drite length present in the normal NL is also found in the manipulated dendrites in experimental animals. Regression and correlation analyses relating the length of dendrites to their longitudinal cross‐sectional area revealed that there was no difference in mean dendritic diameter between the manipulated and unmani‐pulated dendrites in experimental animals. The findings of a high dorsal‐ventral length correlation in experimental animals and a normal spatial gradient of dendritic length among the manipulated dendrites suggests two explanations. Either (1) acoustically evoked synaptic activity is not essential for the develop‐ment of these two aspects of dendritic organization, or (2) the normal NM afferents to the unmanipulated dendrites of each NL neuron in an animal with one ablated otocyst can, under the influence of acoustically driven activity, control develop‐ment of the manipulated dendrites. These alternate hypotheses can be tested experimentally.
Sensory representation in reptilian optic tectum: Some comparisons with mammals
Authors: Stein Barry E. , Gaither Neal S. 
Published: May 2005

AbstractThe sensory representations in the tectum of Iguana iguana were studied with electrophysiological recording techniques, and visual, somatic, and auditory cells were found to be represented here. These cells were not equally distributed throughout the tectal laminae. Upper tectal laminae were populated exclusively by visual cells, and deeper laminae were primarily nonvisual. The intermediate laminae had nonvisual, as well as visual, cells.Maps of the visual and somatic representations were constructed, and both representations were topographic and in register with one another. When electrical stimulation was presented via implanted electrodes, orientation responses were evoked that were predictable on the basis of the visuotopic and somatotopic maps.These organizational features of the iguana tectum are strikingly similar to those described in various mammalian species. It is suggested that the pattern of sensory and motor representation used in the midbrain of mammals is an ancient scheme that was retained during the transition from reptilian to mammalian forms more than 180 million years ago.
Distribution of somatostatin in the frog brain, Rana catesbiana, in relation to location of catecholamine‐containing neuron system
Authors: Inagaki Shinobu , Shiosaka Sadao , Takatsuki Kenichi , Sakanaka Masahiro , Takagi Hiroshi , Senba Emiko , Matsuzaki Takashi , Tohyama Masaya 
Published: May 2005

AbstractThe distribution of somatostatin (SRIF)‐immunoreactive structures in the central nervous system of the bull frog (both with and without treatment of colchicine) was studied, using the indirect immunofluorescence technique of Coons and co‐workers (Coons, '58). SRIF‐containing cells were observed in more than ten areas including the spinal cord. These SRIF‐positive cells showed segmental distribution, in that SRIF‐positive neurons were identified in various areas at various brain levels. An extensive network of SRIF‐positive fibers was found in most parts of the central nervous system. The distribution of a catecholamine (CA)‐containing neuron system in the frog brain is also presented in this study. The possible interactions between SRIF and CA neuron systems are briefly discussed.