bluuebunny/crossref_metadata_2025_split huggingface dataset:
Invariance and sex‐specific variations of the glomerular organization in the antennal lobes of a moth,Mamestra brassicae, and a butterfly,Pieris brassicae
Authors: Rospars Jean Pierre 
Published: May 2005

AbstractThe glomerular organization of the antennal lobes was analyzed in the mothMamestra brassicaeand comparatively in the butterflyPieris brassicae.The invariance of the lobes in number, position, and size of the glomeruli was verified quantitatively in the moth for all the glomeruli in individuals of the same sex (67 in males, 68 in females) and for 56 sex‐invariant glomeruli which can be identified in all individuals whatever their sex. In the butterfly, the positional variability is greater than in the moth and hinders identification. The most conspicuous sex‐variant glomeruli are two adjoining macro‐glomeruli in the male moth which have homologs of very small size in the female. No such dimorph ism was observed inPieris, a species in which males are attracted to female by visual stimuli and not by a sex pheromone as inMamestra.There are other sex‐variant glomeruli inMamestra: four varying in location, three subdivided in the female, two found only in the male, and three found only in the female. Consequently, differing olfactory sensitivity related to species and sex could correlate with detectable modifications in the glomerular organization. A hypothesis on the function of glomeruli is discussed in which most of the glomeruli are viewed as “olfactory general‐ists” giving rise collectively to proposed “across‐glomeruli patterns”.
Subcortical projections to the occipital and parietal lobes of the chimpanzee brain
Authors: Tigges Johannes , Walker Lary C. , Tigges Margarete 
Published: May 2005

AbstractThe subcortical sources of aff erents to occipital andparietal cortex were studied in two chimpanzees with the aid of retrogradely transported horseradish peroxidase (HRP). In chimpanzee 1, HRP was inj ected into right cortical areas 17 and 18; chimpanzee 2 received HRP into right areas 17, 18, 19, and 39. The following subcortical structures were found to project to area 17 and/or area 18: locus coerulcus, dorsalraphe nucleus, nucleus annularis, nucleus centralis superior, pontine reticular formation, mesencephalic reticular formation, dorsal hypothalamus, lateral hypothalamus, nucleus basalis of Meynert, nucleus of the diagonal band of Broca, claustrum, nucleus basalis lateralis amygdalae, lateral geniculate nucleus, inferiorpulvinar.lateralpul‐vinar, nucleus limitans, medial magnocellularpartof the nucleus ventralis anterior, nucleus paraccnlralis, and nucleus centralis medialis thalami. Some of these structures may also project to area 19 and/or area 39. The following thalamic nuclei were found to project to area 19 and/or area 39 but not to areas 17 and 18: nucleus lateralis posterior, nucleus centralis lateralis, nucleus medialis dorsalis, nucleus ventralis lateralis, nucleus ventralis anterior, nucleus lateralis dorsalis, and nucleus anterior ventralis. In several instances, the Hftp‐labeledcells traversed specific nuclear borders, extending uninterruptedly fromone classically definednucleus into another. Thesere‐sults in the chimpanzee largely confirm data from a number of other mammalian taxa on the subcortical sources of afferents to the posterior cortex. Because of the close biological relationship between chimpanzee and man, we feel confident that such projections are also features of the human brain.
Columnar aggregation of prefrorital and anterior cingulate cortical cells projecting to the thalamic mediodorsal nucleus in the monkey
Authors: Arikuni Tomio , Sakai Masaki , Kubota Kisou 
Published: May 2005

AbstractThe columnar arrangement, of the prefrontal and anterior cingulate cortex cells that project to the thalamic mediodorsal (MD) nucleus in rhesus and Formosan monkeys was studied by injecting horseradish peroxidase into the MD nucleus. Labelled cells appeared ipsilaterally in layers V and VI in the dorsolateral, medial, and orbital prefrontal cortex, and in layer VI in the anterior cingulate cortex. Labelled cells were aligned in the radially oriented cords of neurons and grouped into clusters, 25‐200 μm wide, thus forming columns. Radial cellular cords with no labelled cells were interspersed between the labelled radial cords.
Long descending projections of the hypothalamus in the pigeon, Columba livia
Authors: Berk Mitchell L. , Finkelstein Judith A. 
Published: May 2005

AbstractAn autoradiographic analysis was performed on the descending projections of nucleus periventricularis magnocellularis (PVM) of the hypothala‐mus in the pigeon. A PVM‐medullospinal pathway was observed coursing posteriorly through the lateral hypotlialamus, ventrolateral midbrain teg‐mentum, and into the spinal lemniscus (ls) in the ventrolateral pons and medulla. In the pons, some fibers course dorsomedially from ls and terminate at the lateral border of 1 he locus coeruleus. At medullary levels, fibers from ls sweep dorsomedially in the plexus of Horsley and project to certain regions of the nucleus of the solitary tract (NTS) and the dorsal motor nucleus of the vagus (NX). Specifically, PVM fibers project heavily into NTS subnuclei medialis superficialis, medialis ventralis, and lateralis (sulcalis) dorsalis as well as into the ventral parvocellular subnucleus of NX. Fibers in ls were traced caudally into the lateral funiculus as far as upper cervical levels of the spinal cord. Although autoradiographs of lower cervical or thoracic spinal cord sections were not available, PVM fibers do descend to thoracic spinal cord levels, as evidenced by the retrograde transport of horseradish peroxidase.In addition to the medullospinal pathway, the autoradiographs demonstrated PVM projections to septum, diencephalon, and midbrain. Labeled PVM fibers are found in the lateral septal nucleus, nucleus of the anterior pallial commisure, dorsomedial thalamic nucleus, dorsolateral anterior tha‐lamic nucleus (pars ventralis), median eminence, medial and lateral hypo‐thalamus, medial mammillary area, and nucleus intercollicularis and central gray of the midbrain.The projection of fibers to medullospinal regions and median eminence suggests that PVM is homologous to the mammalian par a ventricular nucleus. These projections to specific subnuclei of NTS and NX denote hypo‐thalamic control over certain autonomic functions.
Studies of the principal sensory and spinal trigeminal nuclei of the rat: Projections to the superior colliculus, inferior olive, and cerebellum
Authors: Huerta Michael F. , Frankfurter Anthony , Harting John K. 
Published: May 2005

AbstractWe have analyzed the connections between the sensory trigeminal nuclei and two major sensorimotor areas (i.e., the superior colliculus and crura I and II of the cerebellar cortex) in which tactile input from peri‐oral and other facial regions is a prominent feature. Following injections of horseradish peroxidase into the superior colliculus, retrogradely labeled cells occupy the ventral one chird of the contralateral principal sensory and spinal trigeminal nucleus; trigeminocollicular neurons are especially numerous within, the sub‐nucleus interpolaris (Svi). Injections of either 3H‐proline or horseradish per‐oxidase (HRP) into the Svi reveal that trigeminocollicular axons reach the rostral two‐thirds to three‐quarters of the contralateral superior colliculus, where they distribute in a nonuniform, patchy manner within layers IV‐VI.In addition to demonstrating the trigeminocollicular projection, antero‐grade and retrograde transport studies of the Svi also reveal a trigeminooli‐vary projection which terminates primarily within the contralateral rostral dorsal accessory (DAO) and adjacent principal (PO) olives; some of the Svi neurons innervate both the superior colliculus and the DAO‐PO via axon collaterals.Data from a final set of retrograde tracing experiments show that the trigeminorecipient zone of the DAO‐PO contains neurons which project to crura I and/or II of the cerebellar cortex. Of the various submodalities conveyed by the trigeminal system, it is likely that the trigeminal connections we have demonstrated are carrying tactile information. This is indicated by the fact that responses to tactile stimulation of the face have been reported for cells in (1) the deeper collicular layers, (2) the trigeminorecipient zone of the DAO‐PO, and (3) cerebellar targets of this zone, crura I and II.All data are discussed in the context of the anatomical and physiological literature.
Contralateral termination of primary afferent axons in the sacral and caudal segments of the cat, as studied by anterograde transport of horseradish peroxidase
Authors: Matsushita Matsuo , Tanami Toshio 
Published: May 2005

AbstractContralateral termination of primary afferent axons in the sacral and caudal segments was studied with the anterograde horseradish peroxidase technique in the cat. The distribution of terminals and branching pattern of terminal fibers were examined on sections incubated in a diaminobenzidine‐cobalt chloride medium.The crossed primary afferent axons passing in the dorsal commissure projected to (1) the dorsal gray commissure, (2) small, dorsomedial and ven‐trolateral parts of laminae III and IV, (3) lamina I, and (4) the Xth area (region dorsal to and around the central canal). In the dorsal gray commissure primary afferent axons formed a dense plexus after taking a tortuous course in mediolateral and rostrocaudal directions. Single axons terminated on both sides, but rarely did they extend outside of this region. The axons terminating in the dorsomedial and ventrolateral parts of laminae III and IV passed through the dorsal gray commissure without giving off collaterals. After reaching laminae III and IV they ascended and/or descended within these laminae and terminated at more rostral or caudal levels.The crossed primary afferent axons passing in the ventral commissure terminated in lamina VIII of the Contralateral ventral horn. Some axons terminated in a region ventral to the central canal, and on both sides of lamina VIII.
Retinotopic patterns of connections of area 17 with visual areas V‐II and MT in macaque monkeys
Authors: Weller R. E. , Kaas J. H. 
Published: May 2005

AbstractPatterns of connections of Area 17 with extrastriate visual areas V‐II and MT were studied in macaque monkeys by using 3H‐proline and HRP as anatomical tracers. The results support previous conclusions that V‐II is a split representation of the visual hemifield with most of the outer border formed by the zero horizontal meridian, and that MT is a topological representation of the visual hemifield. V‐II was estimated to be about 10–12 mm wide, 110 mm long along its shared border with V‐I, and 920 mm2in surface area, thereby almost equaling Area 17 in size. MT was judged to be 7 mm wide and 12 mm long, with a surface area of 68 mm2, or roughly 7% of the area of Area 17. In some cases, there was evidence for projections from Area 17 to a third area (or areas) of cortex of about 2 mm wide and of uncertain length on the outer boundary of V‐II. Terminationsin V‐II and MT werecon‐centrated in layer IV and extended into inner layer III. Cells projecting back to Area 17 were largely in layers III and V in V‐II and in layers III and VI in MT.
Enkephalin systems in diencephalon and brainstem of the rat
Authors: Khachaturian Henry , Lewis Michael E. , Watson Stanley J. 
Published: May 2005

AbstractThe immunocytochemical distribution of [Leu]enkephalin and an adrenal enkephalin precursor fragment (BAM‐22P) immunoreactivity was investigated in the diencephalon and brainstem of rats pretreated with relatively high doses of colchicine (300–400 μg/10 μl intracerebroventricularly). The higher ranges of colchicine pretreatment allowed the visualization of extensive enkephalin‐containing systems in these brain regions, some of which are reported for the first time. Immunoreactive perikarya were found in many hypothalamic and thalamic nuclei, interpeduncular nucleus, substan‐tia nigra, the colliculi, periaqueductal gray, parabrachial nuclei, trigeminal motor and spinal nuclei, nucleus raphe magnus and other raphe nuclei, nucleus reticularis paragigantocellularis, vestibular nuclei, several nor‐adrenergic cell groups, nucleus tractus solitarius, as well as in the spinal cord dorsal horn. In addition to the above regions, immunoreactive fibers were also noted in the habenular nuclei, trigeminal sensory nuclei, locus coeruleus, motor facial nucleus, cochlear nuclei, dorsal motor nucleus of the vagus, and hypoglossal nucleus. When adjacent sections to those stained for [Leu]enkephalin were processed for BAM‐22P immunoreactivity, it was found that these two immunoreactivities were distributed identically at almost all anatomical locations. B AM‐22P immunoreactivity was generally less pronounced and was preferentially localized to neuronal perikarya. The results of the present as well as the preceding studies (Khachaturian et ai., '83) strongly suggest substantial structural similarity between the adrenal proenkephalin precursor and that which occurs in the brain. Also discussed are some differences and parallels between the distribution of [Leu]enkeph‐alin and dynorphin immunoreactivities.
Tectal connections in Python reticulatus
Authors: Welker E. , Hoogland P. V. , Lohman A. H. M. 
Published: May 2005

AbstractThe origins of the axons terminating in the mesencephalic tectum in Python reticulatus were examined by unilateral tectal injections of horseradish peroxidase. Kutrogradely labeled cells were observed bilaterally throughout the spinal cord in all subdivisions of the trigeminal system, with the exception of nucleus principalis, which showed labeled cells only on the ipsilateral side. Labeling of the reticular formation occurred bilaterally in nucleus reticular is interiormagnocellularis, nucleus reticularis lateralis, nucleus reticularis medius and the mesencephalic reticular formation. The tectum also receives bilateral projections from the dorsal tegmentaJ field, the nucleus of the lateral lemniscus and nucleus isthmi, and ipsilateral projections from nucleus profundus mesencephali. A few labeled cells were found ipsilaterally in the locus coeruleus and in nuclei vestibulares ventrolateralis and centromedialis. In the diencephalon labeled cells were observed ipsilaterally in nucleus ventrolateralis thalami, nucleus ventromedialis thalami, nucleus suprapeduncularis, and in the dorsal and ventral lateral geniculate nuclei. Bilateral labeling was observed in nucleus periventricularis hypo‐thalami. Furthermore, labeling was ipsilaterally present in the ventral telen‐cephalic areas. The tectum in Python reticulatus receives a wide variety of afferent connections which confirm the role of the tectum as an integration center of visual and exteroceptive information.
Differentiation of cerebellar mossy fiber synapses in the rat: A quantitative electron microscope study
Authors: Hámori József , Somogyi József 
Published: May 2005

AbstractThe differentiation of cerebellar glomeruli was investigated by quantitative electron microscopy, starting with the period at which mossy fibers made their first appearance. Two developmental stages could be delineated in the maturation of the mossy fiber‐granule cell synapse.

A primary growth stage (postnatal days 6–15) characterized by the rapid enlargement of mossy rosettes and the intense proliferation of post‐synaplie dendrites. The synaptic perimeter of mossy terminals, i.e. percentage of membrane surface occupied by synaptic junctions, exhibited a simultaneous, rapid increase in that stage, reaching a peak at postnatal day 15.
Establishment and stabilization of differentiated glomeruli (15th‐45th day). Because the size of mossy rosettes did not change in this period, the increase of glomerular size was due exclusively to the continuing multi plication of postsynaptic dendrites. The characteristic feature of this stage was the massive elimination of synaptic junctions. The synaptic perimeter of 14.4% at day 15 decreased to 5.7% by day 30. Since the size of individual synaptic junctions and the size of mossy terminals did not decrease while the number of postsynaptic dendrites even increased during the same period, the elimination of synaptic junctions represents a net loss of the synaptic perimeter of mossy terminals.
The quantitative analysis suggests that the stabilization of the synaptic perimeter of mossy rosettes at about 6% is due to the elimination during the second developmental stage of immature synapticjunctions, produced in excess during the first growth phase. Also, the observation that synapse elimination and the subsequent stabilization of synaptic perimeter occurs in spite of a steady increase of available postsynaptic dendrites is indicative that the standard 6% value of synaptic perimeter is defined by the presynap‐tic mossy terminal itself.On the basis of these observations, it is also proposed that elimination of synaptic junctions may well occur without the concomitant disappearance of presynaptic and/or postsynaptic neuronal processes.
Altered metabolic activity in the cerebral cortex of rats exposed to ketamine
Authors: Hammer Ronald P. , Herkenham Miles 
Published: May 2005

AbstractUptake of the metabolic marker, [3H]2‐deoxy‐D‐glucose(2DG) was compared in rats given subanesthetic (50–100 mg/kg, i.p.) or anesthetic (200 mg/kg, i.v.) doses of ketamine with that in normal, unanesthetized rats. All doses of ketamine caused a relative increase of 2DG labeling in limbic regions, including the hippocampus, dentate gyrus, and cingulate, piriform, and entorhinal cortices. Striking 2DG‐dense zones were confined to the molecular layer in the hippocampus, dentate gyrus, and entorhinal cortex. Sub‐anesthetic doses of ketamine produced a relative reduction of 2DG uptake in layers 1‐1V of granular somalosensory cortex while sparing up take in layer Va; therefore, the peak of dense uptake shifted from layer IV to layer Va. In regions of the somatosensory cortex which display a dysgranular layer IV, vertical columns of relatively dense 2DG uptake extended through all cortical layers. Columns of 2I) G label also occurred outside of S1, in visual and auditory areas. In the primary visual cortex, this dose of ketamine decreased 2DG uptake relative to secondary visual cortex.Alteration of 2DG uptake in various cortical regions might be the consequence of a ketamine‐induced activation of specific neuronal pathways with special neurochemical features. During subanesthetic ketamine administration, peak 2DG uptake shifts from cortical layer IV, which receives specific thalamocortical input to layer Va which receives projections via intrinsic cortical circuits. The ketamine‐induced shift in the laminar focus of sensory cortical metabolism may reflect a functional disconnection from peripheral sensory input and/or enhanced internal (corticocortical) processing. These changes are more apparent during ketamine administration at doses too low to induce anesthesia and may, therefore, reflect the metabolic events that occur when ketamine and its analogues are taken as drugs of abuse.
Some afferent and efferent connections of the vestibular nuclear complex in the red‐eared turtle Pseudemys scripta elegans
Authors: Pangma G. C. , Donkelaar H. J. Ten 
Published: May 2005

AbstractIn the present study some afferent, commissural, and efferent connections of the vestibular nuclear complex in the turtle Pseudemys scripta elegans were demonstrated with the HRP tracing technique.Afferent projections to the vestibular nuclei were found to arise in the nucleus of the basal optic root, the interstitial nucleus of the fasciculus longi‐tudina Jis medialis, the medial and lateral cerebellar nuclei, the perihypoglos‐sal nuclear complex, and the teticular formation. Distinct commissural projections appeared to arise in the dorsolateral, ventromedial, and descending vestibular nuclei. The commissural projection arising in the ventrolateral vestibular nucleus appeared to be only sparsely developed. Both ascending and descending efferent projections were demonstrated to arise from the vestibularnuclear complex. The ascending vestibulo‐oculomotorprojection was found to be organized in an ipsilateral pathway arising in the dorsolateral vestibular nucleus and in a contralateral pathway, arising mainly in the medial vestibular nucleus. These projections appeared to be directed to the interstitial nucleus of the fasciculus longitudinalis medialis, the oculomotor, trochlear, and abducens nuclei. Also the perihypoglossal nuclear complex appeared to be an important target of vestibular efferents. The origin and course in the brainstem of the descending vestibular projections, i.e., the lateral and medial vestibulospinal tracts, as demonstrated in previous anatomical and experimental studies in reptiles, were confirmed. However, in addition a direct projection of the vestibulospinal tracts to presumably neck motoneurons was found.The organization of the vestibular connections observed in the turtle Pseudemys scripta elegans appeared to be basically comparable to the organization of the vestibular connections in birds and mammals.
The neuronal architecture of the dorsal division of the medial geniculate body of the cat. A study with the rapid Golgi method
Authors: Winer Jeffery A. , Morest D. Kent 
Published: May 2005

AbstractThe neurons in the nuclei of the dorsal division of the medial geniculate body were studied with the rapid Golgi method in kittens and young adult cats. The dorsal nuclei contain two principal cell types: a large stellate neuron with radiate dendrites and a bushy neuron with tufted dendrites, each with extensive dendritic fields. Two sizes of cells with locally arborizing axons (local circuit neurons) were found. The small and commonly observed one is stellate in shape, has a limited dendritic domain, and an axon with multiple, often profuse collaterals ending in the vicinity of the cell. A second, and much less common variety (large local circuit neuron) is somewhat larger and has fewer axon collaterals. Subtle, but distinct variations in these cell types distinguish the deep and superficial dorsal nuclei and also the anterior tier of naclei (deep dorsal and superficial). These functional differences may correlate with the relative morphological homogeneity of the ventral nucleus compared to the extremely heterogeneous medial division. The dorsal division should be regarded as part of the pulvinar‐lateralis posterior complex both structurally and functionally. In the suprageniculate nucleus, the principal neurons are stellate cells with large perikarya and numerous and extensive dendrites covered with appendages. The large axon is devoid of collaterals. A small local circuit cell with several axon collaterals, and sparse, restricted dendrites has also been observed. In the adjacent posterior limitans nucleus, the principal neuron has a medium‐sized, piriform or somewhat elongated Perikaryon, a few very long radiating dendrites, which may span the depth of the nucleus, and a long, poorly branched axon. Small neurons are also seen here.A comparison of the structure, connections, and function of the medial geniculate body suggests that the dorsal division is predominantly, but probably not exclusively auditory, while the ventral nucleus is entirely auditory and relatively homogeneous, and the medial division, polymodal and heterogeneous with respect to input.