bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution and origin of calcitonin gene‐related peptide (CGRP) immunoreactivity in the sensory innervation of the mammalian eye
Authors: Terenghi G. , Polak J. M. , Ghatei M. A. , Mulderry P. K. , Butler J. M. , Unger W. G. , Bloom S. R. 
Published: January 2005

AbstractThe occurrence, distribution, and origin of immunoreactive calcitonin gene‐related peptide (CGRP) in nerves of rat, guinea pig, cat, and monkey eyes were investigated by immunocytochemistry, radioimmunoassay, and chromatography. A rich network of CGRP‐immunoreactive nerve fibres was noted in the anterior uvea, which was widely distributed in both dilator and constrictor papillae muscles and extended to the ciliary body and uveal blood vessels. Numerous CGRP‐immunoreactive neuronal cells were present in the trigeminal ganglion. The extractable CGRP was 8.6 ± 1.8 pmoles/gm of tissue in the iris and 44.0 ± 8.1 pmoles/gm in the trigeminal ganglion. Following damage to the Gasserian ganglion a marked decrease of CGRP immunoreactivity was observed in the anterior uvea (control 11.3± 1.6 pmoles/gm; operated 1.4 ± 0.1 pmoles/gm) confirming the origin of the immunoreactive fibres from trigeminal primary sensory neurons. The sensory nature of the CGRP‐immunoreactive fibres was substantiated by the depletion of CGRP immunoreactivity observed after treatment with capsaicin, which is known to cause selective degeneration of sensory neurons. Comparative studies on the distribution and colocalisation of CGRP and the putative sensory neurotransmitter substance P revealed a closely parallel distribution of the two peptides in certain regions of the uvea and their coexistence in a subpopulation of trigeminal primary sensory neurons. This study suggests that the sensory nervous system in the eye is more heterogeneous in terms of its putative neurotransmitters than previously indicated.
The distribution of substance P, enkephalin, and serotonin immunoreactivities in the area postrema of the rat and cat
Authors: Newton Bruce W. , Maley Bruce , Traurig Harold 
Published: January 2005

AbstractWith the use of the peroxidase‐antiperoxidase technique the distribution of substance P (SP), enkephalin (ENK), and serotonin (5HT) immunoreactivities were described in the area postrema of the rat and cat. In both species, immunoreactivity in the area postrema was differentially distributed as either fibers only, or cell bodies and fibers. In the rat and cat, ENK had the greatest accumulation of immunoreactive fibers, followed by 5HT and SP. In the area postrema of the rat the majority of SP‐, ENK‐, and 5HT‐immunoreactive fibers were along the ventral and ventrolateral borders, with fewer immunostained fibers at the dorsal surface. The area postrema of the cat had the majority of SP‐, ENK‐, and 5HT‐immunoreactive fibers at the ventral and lateral borders, with fewer immunostained fibers at the dorsal and medial borders. In both species, the area postrema's central region contained the fewest immunostained fibers. In general, for each putative neurotransmitter examined, immunostained fibers in both species progressively decreased in number rostrocaudally. Serotonin‐ and ENK‐immunoreactive cell bodies were found in the rat area postrema; in the cat area postrema only ENK‐immunoreactive cell bodies were present. The area postrema of both species lacked SP‐immunoreactive cell bodies. The heterogeneous distribution of immunoreactive fibers and cell bodies within the area postrema of the rat and cat may reflect the different functions of the area postrema in both species.
Cholinergic projections from the basal forebrain to the basolateral amygdaloid complex: A combined retrograde fluorescent and immunohistochemical study
Authors: Carlsen Jørn , Záborszky László , Heimer Lennart 
Published: January 2005

AbstractWe have examined the location of cholinergic and non‐cholinergic neurons that project to the rat basolateral amygdaloid nucleus by using choline acetyltransferase (ChAT) immunohistochemistry in combination with retrograde fluorescent tracing on the same tissue section. Since many tracer‐and ChAT‐positive neurons were identified in basal forebrain areas, including the ventral pallidum, we also stained many of the sections for glutamate decarboxylase, a suitable marker for the delineation of pallidal areas.Cholinergic neurons projecting to the basolateral amygdaloid nucleus were observed in a continuous territory stretching from the dorsal part of ventral pallidum, through sublenticular substantia innominata to ventral parts of globus pallidus and peripallidal areas. Non‐cholinergic neurons projecting to the basolateral amygdaloid nucleus were found intermixed within the same structures and constitute approximately 25% of the amygdalopetal projection neurons in these ventral forebrain structures.Since amygdalopetal cholinergic neurons were demonstrated in areas generally recognized as giving rise to cholinergic projections to cerebral cortex, several retrograde double‐labeling experiments with two different fluorescent tracers were performed for the purpose of detecting the possible existence of collateral projections. The results obtained showed that the cholinergic basal forebrain neurons in general project to only one forebrain region, and, furthermore, that the cholinergic system consists of partially overlapping subsets of neurons that project to various neocortical and allocortical areas and to the amygdaloid body.
The structure of the fourth abdominal ganglion of the crayfish, Procambarus clarki (girard). I. Tracts in the ganglionic core
Authors: Skinner Kate 
Published: January 2005

AbstractThe organization of the fourth abdominal ganglion of the crayfish, Procambarus clarki, was studied with the light microscope in serial sections stained with osmium ethyl gallate. This ganglion is composed of a ventral rind of somata and a core of alternating layers of through‐tracts and commissures. The longitudinal tracts of the ganglion are named according to the system in use for the orthopteran insects, because the basic plans of the crustacean and insect ventral ganglia exhibit striking anatomical parallels. The dorsal tracts are the largest and the most regular in their path through the ganglion. In the ventral posterior quadrant of the ganglion the tracts diverge from the basic plan to pass around the major synaptic neuropil and the bases of the peripheral nerves.This paper reports the three‐dimensional anatomy of the major longitudinal through‐tracts, internal tracts and commissures, and bases of peripheral nerves. Landmark features of the ganglion–including the tracts, the major artery of the vascular system, the shape of the ganglionic core in section, and prominent single cells, all of which make it possible to recognize specific regions of the ganglion–are described.
The structure of the fourth abdominal ganglion of the crayfish, Procambarus clarki (girard). II. Synaptic neuropils
Authors: Skinner Kate 
Published: January 2005

AbstractFour discrete regions of synaptic neuropil in the crayfish fourth abdominal ganglion are described by light and electron microscopy. The largest is the horseshoe neuropil, a horseshoe‐shaped mass of synaptic glomeruli that lies horizontally in the ventral ganglionic core. This neuropil has a substructure of three rings of fused glomeruli associated with the entry of small axons from the first and second nerve roots. The lateral neuropils are large, paired bulges of neuropil that define the sides of the ganglionic core. They contain neuronal profiles of various sizes, filled with clear or dense‐cored vesicles. The neurons are randomly oriented except for occasional dendritic bundles. The tract neuropil is ultrastructurally similar to the lateral neuropils but it is distributed among the largest axons of the through‐tracts and commissures. The midline neuropils are small, U‐shaped clumps of uniformly sized neuronal profiles that contain large numbers of dense‐cored vesicles and distinctive lamellar inclusions.
Neuronal death during development in the isthmo‐optic nucleus of the chick: Sustaining role of afferents from the tectum
Authors: Clarke Peter G. H. 
Published: January 2005

AbstractNeurons have been counted in the isthmo‐optic nucleus following lesions of the optic tectum, its main source of afferents. Late lesions, made at 10.8–12.2 days of incubation, were employed as they cause the fewest nonspecific side effects. The lesions spared the isthmo‐optic tract, and although they caused many retinal ganglion cells to die, the degeneration did not spread to the inner nuclear layer, which contains the target cells of the isthmo‐optic fibers. Hence the effects on the isthmo‐optic nucleus were due to its being deprived of afferents.Even in unoperated embryos, 60% of the isthmo‐optic neurons are known to die between embryonic days 12 and 17. The tectal lesions greatly increased the cell loss ipsilaterally; this was due to cell death, since other explanations such as migration away or differential cellular shrinkage have been ruled out. The fact that additional neuronal death occurred mainly during the latter half of the period of natural cell death implies that the tectal afferents are important for the survival of the isthmo‐optic neurons during this latter half, but not before.
The organization of pudendal motoneurons and primary afferent projections in the spinal cord of the rhesus monkey revealed by horseradish peroxidase
Authors: Roppolo J. R. , Nadelhaft I. , De Groat W. C. 
Published: January 2005

AbstractThe horseradish peroxidase tracing technique was utilized to study the distribution of motoneurons and primary afferent neurons contributing fibers to the pudendal nerve in the monkey. Application of horseradish peroxidase to the central cut end of the pudendal nerve labeled motoneurons in the ipsilateral spinal cord primarily in the S1 and L7 segments. In transverse sections these neurons were distributed within an oval area (Onuf's nucleus) with an average dimension of 360 × 290 μm, located at the base of the ventral horn, medial to the lateral motor nuclei. An average of 418 (range: 170–577) medium‐sized (44 × 26 μm) neurons were labeled per animal. In longitudinal sections the nucleus appeared as a beaded column of cells extending 9.3 mm rostrocaudally with a prominent network of longitudinal dendrites. In the transverse plane, other groups of dendrites were observed: one group extended dorsomedially toward the central canal, while a second group extended dorsolaterally to the intermediolateral gray, with some of the latter dendritic processes following the lateral border of the ventral horn.An average of 9,200 afferent neurons were labeled in the dorsal root ganglia of each animal. Approximately 85% of these cells were located in a single dorsal root ganglion (S1 or S2). This ganglion was always located one spinal segment caudal to the segment containing the majority of cells in Onuf's nucleus. In the spinal cord, afferent labeling in the dorsal columns and Lissauer's tract extended from S3 to at least L1. The density of afferent labeling in the spinal cord paralleled the number of labeled dorsal root ganglion cells in the corresponding segments. From Lissauer's tract and the dorsal columns a prominent collateral fiber bundle passed medially over the apex of the dorsal horn to the dorsal commissure and to medial laminae I–IV of the dorsal horn. A much less prominent pathway passed ventrally along the lateral edge of the dorsal horn to lamina V, where a few collaterals continued medially to the dorsal commissure. The majority of labeled lateral afferent axons ended slightly dorsal to the sacral parasympathetic nucleus.A comparison of the present findings with previous descriptions of the sacral visceral pathways shows a considerable overlap in certain areas of the spinal cord of pudendal and pelvic nerve afferent and efferent systems. This close anatomic relationship is consistent with the physiological observation that somatovisceral integration in the lumbosacral spinal cord is essential for the normal regulation of micturition, defecation, and sexual function.
Neurogenesis of the climbing fibers in the human cerebellum: A Golgi study
Authors: Marin‐Padilla Miguel 
Published: January 2005

AbstractThe prenatal and early postnatal neurogenesis of the human climbing fibers of the lateral cerebellar hemispheres have been studied, with the rapid Golgi method, and correlated with the developmental stages of Purkinje cells. A transitional phase has been established in the neurogenesis of the human Purkinje cell between the second and third stages of Cajal. This phase coincides with the arrival of the climbing fibers. It is characterized by the reabsorption and subsequent transformation of Purkinje cell's basal dendrites into somatic spines. Following the arrival of the climbing fibers and the establishment of contacts, the Purkinje cell is progressively transformed from an immature stellate and nonoriented cell into a monopolar and spatially oriented one which acquires all of its mature morphological and functional features.The human climbing fibers arrive at the Purkinje cell plate by the 28th week of gestation and establish a transient paraganglionic plexus before contacts with these neurons can be recognized. They start to form pericellular nests by the 29th week, and by the 31st week of gestation all Purkinje cells of the lateral hemispheres have pericellular nests around their bodies. These pericellular nests are progressively and rapidly transformed into supracellular “capuchones” which themselves are also short‐lived because the climbing process starts readily in them. Supracellular “capuchones” are recognized by the 34th seek and their fibrils start to climb the dendrites of Purkinje cells (young climbing phase) by the 36th week of gestation. The process of climbing the dendrites of the Purkinje cells will continue through late prenatal and early postnatal life.The human climbing fibers are distributed, in the internal granular layer, within narrow and long vertical territories which are transverse to the long axis of the follium. A single climbing fiber is (1) able to establish contacts with many Purkinje cells located within its narrow territory of distribution; (2) has a tendency to establish contacts with small groups of Purkinje cells rather than with isolate neurons; (3) able to send collaterals to several contiguous cerebellar folia; and (4) able to send collaterals to the internal granular layer and to form pericellular nests in it. The human cerebellum may be considered to be subdivided into a series of parallel, narrow, and transverse structural/functional planes, each one characterized by the distribution of a climbing fiber. It should be emphasized that the axonic collaterals of the Purkinje neurons are similarly distributed and oriented within the internal granular layer and could represent elements of the same flat functional planes. Observations made in this study suggest that the disappearance of the lamina dissecans may be, in part, related to the reabsorption of the Purkinje cell's basal dendrites and hence to the arrival of the climbing fibers.
Organization and distribution of the rat subdiaphragmatic vagus and associated paraganglia
Authors: Prechtl James C. , Powley Terry L. 
Published: January 2005

AbstractThis experiment analyzed the organization of the rat abdominal vagus. To spare delicate tissues and preserve positional information, untrimmed blocks of the subdiaphragmatic viscera (N = 22) were fixed, impregnated by using a pyridine‐silver protocol, and double embedded. Each block was sectioned transversely at 7 μm, and a section every 70 μm from the diaphragm to the cardia was analyzed. The features of the section were traced and digitized for computer reconstruction. Included in the measurements were sizes and locations of bundles, fascicles, and paraganglia.The anterior and posterior vagi were consistently distinctive in size, distribution, cross‐sectional shape, and paraganglionic content. In the most common pattern (41% of animals), the anterior trunk coursed longitudinally on the ventral surface of the esophagus, giving off at successively more distal levels the hepatic branch, the accessory coeliac branch and then the bundles of the anterior gastric branch. The posterior trunk separated into a coeliac branch and a posterior gastric branch, each consisting of numerous bundles, in the most distal quarter of the esophagus. Fifty‐nine percent of all animals exhibited one or more significant variations in vagal organization (e.g., double primary trunks—41%, supernumerary branches—18%, or atypical branching sequences—9%).Four to 14 vagal paraganglia (mean = 8 ± 1; equivalent to 32/rat, corrected for sampling) were found in each animal, and no branch was consistently devoid of paraganglia. Ninety‐four percent of the paraganglia were located at nerve branch points. Some of the larger paraganglia contained at their central poles one to six neurons with soma diameters ranging from 14 to 22 μm.
A Golgi study of the cell types of the dorsal torus semicircularis of the electric fish Eigenmannia: Functional and morphological diversity in the midbrain
Authors: Carr Catherine E. , Maler Leonard 
Published: January 2005

AbstractThe dorsal torus semicircularis (torus) of the gymnotiform fish Eigenmannia was examined in Golgi impregnated material. These results were correlated with those of a previous HRP study which used retrograde labelling techniques to identify the efferent cell types of the torus (Carr et al., '81, J. Comp Neurol. 203: 649–670).The torus is a laminated midbrain nucleus of the electrosensory system. It receives somatotopically ordered electrosensory input from the medulla and caudal lobe of the cerebellum, proprioceptive input from the descending nucleus of the trigeminal nerve, and input from the optic tectum. The torus projects to the nucleus praeeminentialis, the optic tectum, nucleus electrosensorius, parts of the central posterior thalamus, the pretectum, the lateral mesencephalic reticular formation (LMRA), the reticular formation, and the inferior olive.The torus has 12 laminae and 48 cell types by Golgi criteria. There are three major orientations to the dendritic fields of the toral neurons: (1) purely horizontal neurons with dendrites confined to a single lamina, (2) multipolar neurons whose dendrites often do not respect laminar boundaries, and (3) vertical cells with dendrites that travel in the vertical bundles of dendrites and axons which pierce the torus at regular intervals.There are four major groups of vertically oriented neurons. The first has a predominantly horizontal dendritic tree with one or two vertical dendrites which connect the cell to a distant lamina. The second consists of “U”‐shaped neurons with a horizontal arbor and two major dendrites which ascend in adjacent vertical bundles. The third group is made up of bilaminar neurons which receive input from two vertically separated dendritic arbors, and the fourth group is purely vertical in orientation. A group of four tegmental cell types in the LMRA also send their dendrites into the efferent tracts of the torus, and into lamina IX.The torus is similar in complexity and number of cell types to the mammalian inferior colliculus. The large number of cell types in these midbrain sensory nuclei, compared to the number of afferent inputs (seven or more for the torus) is notable and may reflect the parcellation of function associated with the parallel processing of these inputs.
Localization of the synthetic progestin 3H‐ORG 2058 in neurons of the primate brain: Evidence for the site of action of progestins on behavior
Authors: Rees Howard D. , Bonsall Robert W. , Michael Richard P. 
Published: January 2005

AbstractThe location of neurons that concentrate progestin in the brains of female cynomolgus monkeys was mapped by autoradiography using the specific synthetic progestin receptor ligand 3H‐ORG 2058. Three females were ovariectomized and treated with estrogen (20 μg estradiol benzoate daily for 7 days), and one of them was also pretreated with progesterone. Each received an i.v. injection of 1 mCi 3H‐ORG 2058 and was killed 1 hour later. Thaw‐mount autoradiograms revealed intense accumulation of radioactivity in the nuclei of many neurons in the mediobasal hypothalamus, particularly in the ventromedial nucleus (n.), arcuate n., and premammillary n. Neuronal labeling was also observed frequently in the medial preoptic n., and occasionally in the anterior hypothalamic area, paraventricular n., and organum vasculosum of the lamina terminalis. In the pituitary gland, about 5% of cells in the pars distalis were intensely labeled. In the female pretreated with progesterone, however, labeling was almost completely blocked. Analysis of samples by high‐performance liquid chromatography demonstrated that the radioactivity extracted from brain and pituitary gland cell nuclei was almost entirely unmetabolized 3H‐ORG 2058. The nuclear concentration of progestin was much greater in the pituitary gland than in the brain, and was greater in the hypothalamus than in any other brain area. These results revealed well‐localized groups of progestin‐concentrating neurons in the primate brain which presumably mediate the effects of progresterone on both gonadotropin secretion and female sexual behavior.
Topographic organization of tufted cell axonal projections in the hamster main olfactory bulb: An intrabulbar associational system
Authors: Schoenfeld Thomas A. , Marchand James E. , Macrides Foteos 
Published: January 2005

AbstractThe organization of intrinsic axonal projections of principal neurons in the main olfactory bulb (MOB) was studied in hamsters by using wheat germ agglutinin‐horseradish peroxidase (WGA‐HRP) and fluorescent dyes. Punctate injections of either WGA‐HRP or fast blue (FB) that are restricted to small sectors on one side of the MOB produce comparably restricted fields of retrograde labeling on the opposite side. Label is found predominantly in superficially situated (middle and external) tufted cells that lie near and at the border between the external plexiform and glomerular layers. Few of the deeper middle tufted, internal tufted, or mitral cells and no external tufted cells that lie in the superficial two‐thirds of the glomerular layer are labeled in regions remote to the injection site. Anterograde transport of WGA‐HRP from the injection site labels axons that travel dorsally and ventrally in restricted bands through the internal plexiform layer and then terminate within this layer in the punctate sector on the opposite side that contains retrogradely labeled neurons. Such reciprocal projections between opposing regions of the medial and lateral sides of the MOB are found at all rostrocaudal and dorsoventral levels. When punctate injections of FB into the MOB are paired with restricted injections of a second fluorescent tracer (nuclear yellow or diamidino yellow dihydrochloride) into the appropriate sector of pars externa (pE) of the anterior olfactory nucleus, the punctate region of remote retrogradely labeled principal neurons is embedded within a topographically restricted longitudinal wedge of retrogradely labeled mitral and tufted cells that project extrinsically to or through pE. However, extremely few of these neurons are double‐retrogradely labeled. The results reveal the existence of an intrabulbar associational system in which principal neurons engage in point‐to‐point, reciprocal projections between opposing regions of the medial and lateral MOB. Moreover, the results indicate that this associational system largely arises from superficially situated tufted cells distinct from those that support bulbofugal projections into the topographically organized interbulbar commissural system via pE.