bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural and functional organization of a diencephalic sensory‐motor interface in the gymnotiform fish, Eigenmannia
Authors: Keller Clifford H. , Maler Leonard , Heiligenberg Walter 
Published: January 2005

AbstractThe diencephalic nucleus electrosensorius (nE) of gymnotiform fish comprises a series of finely tuned neuronal filters for control of the jamming avoidance response (JAR) and probably other electromotor tasks as well. The nE receives electrosensory input from the dorsal torus semicircularis (TSd) and octavolateral input from the ventral torus (TSv). The nE, in turn, projects to various hypothalamic and thalamic nuclei, including the prepacemaker nucleus (PPn), which can modulate the frequency of electric organ discharges (EODs) via its unique input to the medullary pacemaker nucleus.Four subdivisions of the nE can now be recognized: 1) The beat‐related area (nEb)‐‐‐a rostral cluster of tightly packed cells which receives TSd input and projects to the inferior lobe, anterior tuberal nucleus, anterior thalamic nucleus, central posterior thalamic nucleus, and PPn. The nEb contains neurons responsive to beat patterns caused by jamming stimuli. Stimulation of the nEb with L‐glutamate, however, fails to induce any EOD‐frequency shift. 2) The area causing EOD‐frequency rises (nE↑)‐‐a horizontal band of cells at the dorsal aspect of the caudal nE which receives TSd input and projects to the PPn and vicinity and to the cerebellum; nE↑ stimulation induces slow EOD‐frequency rises characteristic of the JAR. Responses of these cells to jamming stimuli are not yet known. 3) The area causing EOD‐frequency falls (nE↑)‐‐a horizontal band of cells at the ventral aspect of the caudal nE which receives TSd input and projects only to the PPn and vicinity; nE↑ stimulation induces slow EOD‐frequency falls characteristic of the JAR. The responses of these cells to jamming stimuli are not yet known. 4) The acousticolateral region (nEar)‐‐‐a complex medial region of the nE which receives input predominantly from the ventral torus and projects to the inferior lobe, anterior tuberal nucleus, central posterior thalamic nucleus, PPn, and cerebellum; the sensory and motor properties of this region are not known in detail, although auditory and mechanosensory responses have been recorded here. Projections to the PPn and its vicinity suggest direct control of electromotor behaviors by the nE, whereas thalamic and hypothalamic projections may provide a substrate for electrosensory influences on neuroendocrine and motivational control centers.The optic tectum projects strongly to the pretectum and various other diencephalic nuclei in the vicinity of the nE, but it does not innervate the nE itself. Accordingly, ablation of the tectum does not affect the performance of the JAR.
Anatomical studies of dorsal column axons and dorsal root ganglion cells after spinal cord injury in the newborn rat
Authors: Lahr Stephen P. , Stelzner Dennis J. 
Published: January 2005

AbstractThe response of dorsal column axons was studied after neonatal spinal overhemisection injury (right hemicord and left doral funiculus). Rat pups (N = 11) received this spinal lesion at the C2 level within 30 hours after birth. The cauda equina was exposed 3 months later in one group of chronic operates (N = 5) and in a group of normal aduits (N = 2), and all spinal roots from L5 caudally were cut bilaterally; 4 days later the spinal cord and medulla were processed for Fink‐Heimer impregnation of degenerating axons and terminals. In a second group of chronic operates (N = 6) and normal adult controls (N = 4) the left sciatic nerve was injected with a cholera toxin‐HRP conjugate (C‐HRP), followed by a 2–3 day transganglionic transport period, and then the spinal cord and medulla were processed with tetramethylbenzidine histochemistry. Both control groups have a consistent dense projection in topographically adjacent regions of the dorsal funiculus and gracile nucleus. However, there is no sign of axonal growth around the lesion in either group of chronic experimental operates. Instead, there is a decreased density of projection within the dorsal funiculus near the lesion site. Many remaining C‐HRP labeled axons in the experimental operates have abnormal, thick varicosities and swollen axonal endings (5–10 μm × 10–30 μm) within the dorsal funiculus through several spinal segments caudal to the lesion. Ultrastructural analysis of the dorsal funiculus in three other chronic experimental operates reveals the presence of numerous vesicle filled axonal profiles and reactive endings which appear similar to the C‐HRP labeled structures.Transganglionic labeling after C‐HRP sciatic nerve injections (N = 4) and retrograde labeling of L4, L5 dorsal root ganglion neurons after fast blue injections of the gracile nucleus (N = 6) both suggest that all dorsal column axons project to the gracile nucleus in the newborn rat. Dorsal root ganglion (DRG) cell survival following the neonatal overhemisection injury was also examined in the L4 and L5 DRG. DRG neurons that project to the gracile nucleus were prelabeled by injecting fast blue into this nucleus at birth two days prior to the cervical overhemisection spinal injury. Both normal littermates (N = 9) and spinally injured animals (N = 12) were examined after postinjection survival periods of 10 or 22 days. Comparison of the percentage and number of labelled and unlabeled DRG neurons in the L4 and L5 ganglia in control and experimental operates reveals no sign of cell loss after neonatal dorsal colomn axotomy.We conclude that dorsal column axons do not grow around damage to their normal pathway in the newborn rat during a period when previous studies show adjacent corticospinal axons are able to grow around the same type of spinal injury and when the spinal environment normally permits growth of the still elongating corticospinal tract axons to occur.
Evidence for a functional and anatomical relationship between the lateral septum and the hypothalamus in the control of flank marking behavior in golden hamsters
Authors: Ferris Craig F. , Gold Larry , De Vries Geert J. , Potegal Michael 
Published: January 2005

AbstractGolden hamsters with established dominant/subordinate relationships communicate their social status by rubbing pheromone‐producing flank glands against objects in the environment. This behavior, called flank marking, is controlled by vasopressin‐sensitive neurons localized to the anterior hypothalamus. Vasopressinergic magnocellular neurons in the nucleus circularis and medial aspect of the supraoptic nucleus are thought to be a source of neurotransmitter for the initiation of flank marking.The present study was undertaken to examine the extrahypothalamic control of flank marking. The anatomical and functional connections between the lateral septum and the vasopressin‐containing nuclear groups in and around the anterior hypothalamus were examined by: (1) tracing afferent and efferent connections following microinjection of horseradish peroxidase and Phaseolus vulgaris‐leucoagglutinin into the lateral septum, and (2) recording odor‐induced flank marking prior to and following ibotenate lesions in the septum.The greatest number of perikarya retrogradely labeled with horseradish peroxidase were found lateral to the anterior hypothalamus and ventral to the fornix in the area of the lateral hypothalamus. The vasopressin‐containing nuclear groups, e. g., paraventricular, supraoptic, suprachiasmatic nuclei, and the nucleus circularis, were devoid of labeled perikarya. Nerve terminals anterogradely labeled with Phaseolus vulgaris‐leucoagglutinin were primarily localized to the anterior hypothalamus, in and around the nucleus circularis, and the medial aspect of the supraoptic nucleus. The lateral aspect of the supraoptic nucleus was devoid of nerve terminals as were the paraventricular and suprachiasmatic nuclei. The anatomical connections between the lateral septum and the hypothalamus appear to be necessary for the control of flank marking, since the microinjection of ibotenate into this limbic site significantly reduced odor‐induced flank marking as compared to control microinjections of 0.9% NaCl.
Connections of the parabrachial nucleus with the nucleus of the solitary tract and the medullary reticular formation in the rat
Authors: Herbert Horst , Moga Margaret M. , Saper Clifford B. 
Published: January 2005

AbstractWe examined the subnuclear organization of projections to the parabrachial nucleus (PB) from the nucleus of the solitary tract (NTS), area postrema, and medullary reticular formation in the rat by using the anterograde and retrograde transport of wheat germ agglutinin‐horseradish peroxidase conjugate and anterograde tracing with Phaseolus vulgaris‐leucoagglutinin. Different functional regions of the NTS/area postrema complex and medullary reticular formation were found to innervate largely nonoverlapping zones in the PB.The general visceral part of the NTS, including the medial, parvicellular, intermediate, and commissural NTS subnuclei and the core of the area postrema, projects to restricted terminal zones in the inner portion of the external lateral PB, the central and dorsal lateral PB subnuclei, and the “waist” area. The dorsomedial NTS subnucleus and the rim of the area postrema specifically innervate the outer portion of the external lateral PB subnucleus. In addition, the medial NTS innervates the caudal lateral part of the external medial PB subnucleus.The respiratory part of the NTS, comprising the ventrolateral, intermediate, and caudal commissural subnuclei, is reciprocally connected with the Kölliker‐Fuse nucleus, and with the far lateral parts of the dorsal and central lateral PB subnuclei. There is also a patchy projection to the caudal lateral part of the external medial PB subnucleus from the ventrolateral NTS.The rostral, gustatory part of the NTS projects mainly to the caudal medial parts of the PB complex, including the “waist” area, as well as more rostrally to parts of the medial, external medial, ventral, and central lateral PB subnuclei.The connections of different portions of the medullary reticular formation with the PB complex reflect the same patterns of organization, but are reciprocal. The periambiguus region is reciprocally connected with the same PB subnuclei as the ventrolateral NTS; the rostral ventrolateral reticular nucleus with the same PB subnuclei as both the ventrolateral (respiratory) and medial (general visceral) NTS; and the parvicellular reticular area, adjcent to the rostral NTS, and with parts of the central and ventral lateral and the medial PB subnuclei that also receive rostral (gustatory) NTS input. In addition, the rostral ventrolateral reticular nucleus and the parvicellular reticular formation have more extensive connections with parts of the rostal PB and the subjacent reticular formation that recieve little if any NTS input.The PB contains a series of topographically complex terminal domains reflecting the functional organization of its afferent sources in the NTS and medullary reticular formation.
Postnatal development of palatal and laryngeal taste buds in the hamster
Authors: Belecky Teri L. , Smith David V. 
Published: January 2005

AbstractMammalian taste buds are distributed within several distinct subpopulations, innervated by branches of three cranial nerves. These taste bud populations originate and mature at different times in various mammalian species and are thought to play differential roles in the control of taste‐mediated behaviors. The hamster is a common animal for the electrophysiological study of the gustatory system, and it has been shown that taste buds innervated by the IXth nerve develop postnatally in this species. To delineate further the development of the gustatory system of hamsters, we quantified the number of taste buds appearing on the palatal, nasopharyngeal, and laryngeal epithelium from birth through 120 days of age. Taste buds are present in almost adult numbers on the soft palate at birth, but only 39% of these are mature. Distinct taste pores, indicative of mature taste buds, increase in number until about 20‐30 days of life, at which time all of the taste buds on the soft palate and on the nasoincisive papillae are fully developed. Taste buds are concentrated primarily on the posterior and medial portions of the soft palate. Taste buds located on the laryngeal surface of the epiglottis and the aryepiglottal folds are absent at birth and originate and mature over the following 120 days. Laryngeal taste buds are more concentrated on the aryepiglottal folds than on the epiglottis. On the soft palate and in the epiglottal region, the maturation of taste buds is well characterized by a logarithmic function (Y=a log X + B) relating the number of mature taste buds to postnatal age. On the soft palate, the length of the taste buds from base to apex correlates with the thickness of the epithelium, which increases with development. The diameter of mature taste buds on the soft palate does not change with age. In contrast to many mammalian species, in rodents taste bud development occurs mostly after birth. Rapid postnatal development progresses at a time when ingestive behavior is undergoing a number of significant changes. Taste buds in the larynx have been implicated in a number of laryngeal reflexes (i.e., apnea, swallowing) in several nonrodent species. The electrophysiological properties of superior laryngeal nerve fibers would suggest a similar function for epiglottal taste buds in the hamster.
Migratory pathways and selective aggregation of the lateral reticular neurons in the rat embryo: A horseradish peroxidase in vitro study, with special reference to migration patterns of the precerebellar nuclei
Authors: Bourrat Franck , Sotelo Constantino 
Published: January 2005

AbstractThe migration and ultimate domain invasion of postmitotic lateral reticular nucleus (LRN) neurons were followed in embryonic day 15–20 (E15‐E20)rat embryos, by using a horseradish peroxidase (HRP) in vitro axonal tracing method. All of the LRN axons elongate and neuronal somata migrate via the subpial or marginal migratory stream (mms), circumnavigating the ventrolateral aspect of the medulla at the glial endfeet level. They reach the ventral midline at E16, bypass it, and begin to settle in their final territory at E17. At E18 the LRN anlage is fully formed, and at E19‐E20 its cells have finished their migration and are rapidly differentiating. Comparison of these sequential steps with their counterparts in the development of the inferior olive (ION) and external cuneatus (ECN) brings to light the essential role of the neuroepithelial cells of the interolivary commissure (the “floor plate”). This zone is likely to act as (1) a chemoattractant for the growth cones of the LRN, ION, and ECN, and (2) a decision‐making center, which instructs the somata of these neurons to cross the midline or not, ultimately governing the crossed or uncrossed pattern of their projection to their common target, the cerebellum. Finally, the ontogeny of the LRN and ECN provides a most surprising example, even unique in the central nervous system, of long‐distance, neurophilic migration that conveys neuronal cell bodies contralaterally to the side on which they proliferate.
Expression of compartmentation antigen zebrin I in cerebellar transplants
Authors: Wassef Marion , Sotelo Constantino , Thomasset Monique , Granholm Ann‐Charlotte , Leclerc Nicole , Rafrafi Jamel , Hawkes Richard 
Published: January 2005

AbstractThe mammalian cerebellum is divided into multiple parasagittal compartments as defined by the organization of afferent and efferent projections and by the pattern of expression of several biochemical markers. One such marker is the antigen zebrin I, a 120 kD polypeptide of unknown function that is expressed differentially by a subset of Purkinje cells. Zebrin I+ Purkinje cells are grouped into an array of 14 parasagittal bands interposed by zebrin I− compartments. This Purkinje cell compartmentation corresponds to compartments in the olivocerebellar projection. The afferent axon compartments are present prior to the expression of the mature zebrin I phenotype, thus raising the possibility that differential afferent input regulates the zebrin I phenotype of the target of that input. Lesion studies in the neonate preclude a role for afferent inputs in the regulation of zebrin I expression postnatally, but a prenatal role in commitment still remains open. To explore this possibility, cerebellar anlagen were dissected from embryos at embryonic days 12–15, that is, prior to any contact with afferents, and transplanted ectopically into adult hosts. In the first series of experiments, the grafts were placed into the anterior chamber of the eye, and in the second series, into cavities prepared in the neocortex. Grafts were allowed to mature and then were immunoperoxidase or immunofluorescence stained for zebrin I immunoreactivity. Zebrin I was expressed by grafted Purkinje cells in cortico and in oculo. Double‐labelling experiments confirmed that both the zebrin I+ and the zebrin I− phenotypes were present. The zebrin I immunoreactivity revealed that the zebrin I+ Purkinje cells resemble those in situ with an extensive dendritic arborization that extends through the molecular layer perpendicular to the long axes of the folia. In conclusion, the present data suggest that afferent input does not play a role in the determination of the zebrin I phenotype of Purkinje cells.
Ultrastructure of substance P‐ and CGRP‐immunoreactive nerve fibers in the nasal epithelium of rodents
Authors: Finger Thomas E. , Jeor Var L. St. , Kinnamon John C. , Silver Wayne L. 
Published: January 2005

AbstractThe respiratory and olfactory mucosae of rats and mice were examined at ultrastructural levels for the presence of intraepithelial nerve endings. Immunocytochemical studies utilizing antisera directed against substance P and calcitonin gene‐related peptide (CGRP) revealed numerous intraepithelial peptide‐immunoreactive fibers near the basal region of the epithelium. Occasional transepithelial fibers were observed to extend outward to nearly reach the epithelial surface. In no cases, however, did the transepithelial fibers reach the surface, but instead, stopped at the line of tight junctions approximately 1 μm from the surface. No specialized contacts between the nerve fibers and the epithelial cells were observed. The transepithelial fibers provide a possible anatomical substrate for the sensitivity of the trigeminal nerve to many air‐borne chemical stimuli. That potential chemical stimuli must traverse the tightjunctional barrier may explain why lipid solubility is related to effectiveness for trigeminal stimuli.
Involvement of specific placental antigen X‐P2 in rat olfaction: An immunohistochemical study in the olfactory bulb
Authors: Shinoda Koh , Yagi Hideo , Osawa Yoshio , Shiotani Yahe 
Published: January 2005

AbstractHuman placental antigen X‐P2 (hPAX‐P2), an antigen complex associated with cytochrome P‐450 of aromatase within estrogen synthesizing tissues, has been reported to be present in a distinct group of rat primary olfactory receptors involved in suckling behavior. In this study, most of the mitral and tufted cells in the rat olfactory bulb were found to possess hPAX‐P2 immunoreactivity. This suggests that the activity of these cells can be hormonally modulated and that hPAX‐P2 is involved in rat olfaction not only at the receptor level but also at integrative brain levels via the secondary projecting neurons of the olfactory pathway.
Neuropeptide diversity in Ascaris: An immunocytochemical study
Authors: Sithigorngul Paisarn , Stretton Antony O. W. , Cowden Cynthia 
Published: January 2005

AbstractAn immunocytochemical method was used for localization of various peptide‐like substances in the Ascaris nervous system. Out of 45 antipeptide antisera, 12 demonstrated immunoreactivity in different subsets of neurons; these 12 antisera were raised against luteinizing hormone‐releasing hormone (LHRH), Aplysia peptide L11 (L11), Aplysia peptide 12B (12B), small cardioactive peptide B (SCPB), neuropeptide Y (NPY), FMRFamide, gastrin‐17, cholecystokinin octapeptide (CCK‐8), α‐melanocyte stimulating hormone (α;MSH), calcitonin gene related peptide (CGRP), corticotropin releasing factor (CRF), and vasoactive intestinal peptide (VIP). Several peptide‐like substances were colocalized to the same neuron. Our results suggest that Ascaris, like other organisms, contains multiple peptidergic systems.
Connections of the subthalamic nucleus with ventral striatopallidal parts of the basal ganglia in the rat
Authors: Groenewegen Henk J. , Berendse Henk W. 
Published: January 2005

AbstractThe present study was undertaken to establish the precise anatomical relationship of the subthalamic nucleus (STh) with limbic lobe‐afferented parts of the basal ganglia in the rat. The anterograde tracer Phaseolus vulgaris‐leucoagglutinin (PHA‐L), injected in the STh, the globus pallidus, the ventral pallidum, the ventral striatum, and the parafascicular thalamic nucleus, and the retrograde tracers Fluoro‐Gold (FG) and cholera toxin B (CTb), injected in the globus pallidus, the ventral pallidum, the ventral striatum, and the ventral mesencephalon, were used for this purpose. The results of these tracing experiments confirm the general notion of reciprocal connections between the STh and pallidal areas. Thus the dorsomedial part of the STh is connected with the subcommisural ventral pallidum, whereas a more ventral and lateral part of the medial STh is related to the medial globus pallidus. The lateral hypothalamic area, directly adjacent to the STh, containing neurons with a morphology quite similar to those in the STh, projects to parts of the ventral pallidum related to the olfactory tubercle. The reciprocal projection from this pallidal area to subthalamic regions appears to be very sparse. The medial STh sends strong projections to the medial part of the entopeduncular nucleus and the adjacent lateral hypothalamic area. Sparser projections from the medial STh reach the rostral and medial part of the caudate‐putamen and the nucleus accumbens. The nucleus accumbens. The nucleus accumbens sends a very sparse projection back to the medial STh. The projections of the medial STh to the ventral mesencephalon appear also to be topographically organized. The lateral hypothalamus and a few cells in the most medial part of the STh project to the ventral tegmental area, whereas progressively more lateral parts of the ventral mesencephalon, in particular the substantia nigra, receive input from successively more lateral and caudal parts of the STh. In addition, a number of STh fibers reach the midbrain extrapyramidal area. The lateral part of the parafascicular thalamic nucleus projects to the lateral part of the STh, whereas parafascicular neurons medial to the fasciculus retroflexus projects to the dorsomedial portion of the STh.The medial part of the STh and the adjacent lateral hypothalamus are intimately connected with limbic parts of the basal ganglia in a way similar and parallel to the connections of the lateral STh with motor‐related parts of the basal ganglia. These findings suggest a role for the STh in nonmotor functions of the basal ganglia.