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R Y Moore

Publications and source records attributed to R Y Moore.

At least 127 records · Page 7Linked to original sources
PubMed1981

Innervation of the thymus gland by brain stem and spinal cord in mouse and rat.

Central nervous system (CNS) projections to the thymus were studied in the mouse and rat using the horseradish peroxidase (HRP)-retrograde transport method. With discrete HRP injections localized to the thymus, labeled neurons are evident in both medulla and spinal cord. In the medulla the largest population of labeled neurons is present in the retrofacial nucleus. Within this cytoarchitectonically distinct nucleus, the majority of neurons are labeled with large HRP injections in the thymus. In addition to retrofacial nucleus, scattered labeled neurons are found throughout the rostrocaudal extent of the nucleus ambiguus and in the dorsal medullary tegmentum adjacent to the dorsal motor vagus nucleus. With HRP injections restricted to thymus parenchyma, no labeled neurons are evident in the dorsal motor vagus nucleus. Three groups of spinal cord neurons are labeled. In segments C2-C4, neurons localized to the ventral horn are labeled in two distinct columns, one located lying laterally in the ventral horn and the other located medially. Labeling of neurons in these segments is distinct from that of large motor neurons located medially in the ventral horn extending from the level of the decussation of the pyramids through the C1 segment. The location and sizes of neurons labeled in these areas following HRP injection in the thymus are identical in the mouse and rat. These observations provide evidence for previously unknown projections from spinal cord and brain stem to the thymus which may play an important role in the regulation of thymic function.

Animals↗
PubMed1981

Presence of beta-endorphin-like immunoreactivity in the anterior pituitary gland of rat and man and evidence for the differential localization with ACTH.

Two antisera, Y-10 and Y-18 were raised in rabbits against synthetic human beta-endorphin conjugated to bovine serum albumin and keyhole limpet haemocyanin respectively. Antiserum Y-10 has been shown by radioimmunoassay to be highly specific for human beta-endorphin with minimal or no cross-reactivity against other pituitary peptides whilst antiserum Y-18 cross-reacted on an equimolar basis against beta-endorphin and beta-lipotropin. When used in the immunohistochemical procedure, both antisera specifically stained the corticotrophs in human anterior pituitary tissue. A similar effect was observed when antiserum Y-18 was applied to rat anterior pituitary tissue in the immunohistochemical procedure. Y-10 antiserum, on the other hand, stained not only rat corticotrophs but also somatotrophs. The somatotrophin staining could not be attributed to the enkephalins reported to be present in these cells. The non-specific beta-endorphin antiserum Y-18 was used to stain anterior pituitaries from dehydrated and adrenalectomized rats as well as rats of the Brattleboro strain. In tissues from the three experimental animals, cells that stained positively for beta-endorphin did not give a positive immunoreaction for ACTH and vice versa in some other sections. It is concluded that under the physiological conditions, formalin fixation of the tissue causes the pro-opiocortin molecule to be "trapped" in a conformation such that either ACTH or beta-endorphin-like determinants are available for reacting with the appropriate antiserum.

Adrenocorticotropic Hormone↗
PubMed1981

A retinal projection to the lateral hypothalamus in the rat.

This study presents evidence for a retinal projection to neurons in the lateral hypothalamic area (LHA) of the albino rat. In Golgi-Kopsch material dendrites from LHA-neurons are observed to extend through the supraoptic commissures into the optic tract. The presence of dendrites in the optic tract is confirmed by electron microscopy. Numerous axon terminals are observed forming asymmetric synaptic contacts with these dendritic profiles. Following bilateral enucleation, many of the preterminal axons and terminals in synaptic contact with dendrites in the optic tract demonstrate dark degeneration. After intraocular injection of horseradish peroxidase, there is marked labeling of preterminal axons and terminals in the optic tract. These observations indicate that LHA neurons receive a direct retinal projection from terminals making synaptic contact with dendrites of LHA-neurons extending into the optic tract.

Animals↗
PubMed1981

Immunocytochemical localization of vasoactive intestinal polypeptide-containing cells and processes in the suprachiasmatic nucleus of the rat: light and electron microscopic analysis.

The distribution of vasoactive intestinal polypeptide-like (VIP) immunoreactivity in neurons and processes within the suprachiasmatic nuclei (SCN) of the rat was investigated with light and electron microscopic immunocytochemical techniques. These studies utilized well characterized antisera directed to synthetic vasoactive intestinal polypeptide. Specificity was established by absorption of the antisera with synthetic vasoactive intestinal polypeptide. Neurons and dendrites exhibiting specific VIP immunoreactivity are concentrated in the ventral half of the nucleus, with the greatest concentration of immunoreactive perikarya occurring in the ventral SCN immediately adjacent to and within the optic chiasm (OC). Thin varicose axons containing VIP immunoreactivity are present throughout the SCN. A large number of immunoreactive axons leave the dorsal aspect of the SCN to reach the periventricular hypothalamic nucleus and continue dorsally to form an extensive plexus along the ventral border of the paraventricular hypothalamic nucleus. Other immunoreactive axons project upon the contralateral SCN via the OC. Ultrastructurally, VIP-containing neurons in the SCN are characterized by a spherical to slightly elongated soma and an invaginated nucleus that fills the majority of the cell body. In the soma, peroxidase reaction product is localized on the outer membrane of all cellular organelles. The reaction product of immunoreactive boutons is related primarily to vesicles, and some of these boutons establish axodendritic synaptic contacts in the SCN. The demonstration of VIP-containing neurons in the SCN provides further evidence that this nucleus is composed of a heterogeneous population of neurons which form distinct subfields within it.

Animals↗
PubMed1980

Selective effects of kainic acid on diencephalic neurons.

Injections of kainic acid (KA) into the lateral hypothalamus (LH) produce neuronal loss in this region without apparent damage to medial forebrain bundle fibers passing through the area. Cellular destruction is not limited to the LH; the neuronal loss in the thalamic reticular nucleus, the subthalamic nucleus and zona incerta is more extensive than that in the LH. Since all of the nuclei of ventral thalamic origin except the ventral lateral geniculate nucleus (VLGN) were destroyed by LH injections of KA, we sought to determine whether this nucleus also is sensitive to KA. Injections directly into the VLGN produce total neuronal loss here as well as in the thalamic reticular nucleus, zona incerta and subthalamic nucleus. Other areas showing cell loss are the dorsal LGN, medial geniculate, lateral portion of the ventrobasal complex and midline thalamic nuclei. Injections of KA into medial hypothalamus adjacent to the suprachiasmatic nucleus produced no neuronal degeneration. In addition, no neuronal loss was noted in medial hypothalamic nuclei lying adjacent to areas of LH in which KA was injected. Therefore, the sensitivity of diencephalic nuclei appears to range from highly sensitive regions such as derivatives of ventral thalamus and midline thalamic nuclei to regions of moderate sensitivity such as the LH, geniculate nuclei and ventrobasal thalamic nucleus, to regions resistant to KA toxicity such as the suprachiasmatic nucleus and other nuclei and areas of medial hypothalamus.

Animals↗
PubMed1980

Interpeduncular nucleus afferents in the rat.

Afferents to the interpeduncular nucleus (IPN) of the rat were studied with the horseradish peroxidase (HRP) retrograde transport method. HRP was deposited microelectrophoretically in the IPN of adult rats. Major projections to the IPN originate in the medial habenular nucleus, the region surrounding the dorsal tegmental nucleus (accessory dorsal tegmental nucleus and the so-called dorsal tegmental nucleus pars lateralis), and the midbrain raphe (nucleus centralis superior and nucleus raphe dorsalis). Also, minor projections originate in the central gray and nucleus locus coeruleus. Our results indicate that the habenulointerpeduncular projection originates solely from the medial habenular nuclei and is topographically organized; medial regions of the medial habenular nuclei project to ventral portions of IPN and lateral regions project to the dorsal IPN.

Afferent Pathways↗
PubMed1980

Noradrenergic innervation of the adult rat hippocampal formation.

The noradrenaline (NA)-containing innervation of the hippocampal formation arises exclusively in the brainstem nucleus locus coeruleus. The projection is 75--90% ipsilateral, originating predominantly in the large, multipolar cells of the compact component of the nucleus. The axons course into the hippocampal formation by three pathways. Ammon's horn receives its NA innervation principally through the ventral amygdaloid bundle-ansa peduncularis, with smaller contributions from the fornix and ipsilateral fasciculus cinguli. The innervation of the area dentata is to a larger extent bilateral, with the greatest contribution arising from the ipsilateral fasciculus cinguli and approximately equal proportions of fibers traveling via the contralateral cingulum, fornix, and the ventral path. In general, the endogenous content of NA is greater in the area dentata than in Ammon's horn, and in both structures is greater in the temporal than in the septal ends. The pattern of NA innervation is similar at all septotemporal levels, however. The dense plexuses of preterminal and terminal elements appear in the infragranular hilus of the area dentata, stratum lucidum of CA3, and in the molecular layer of the subiculum. Fluorescent varicosities often appear in perisomatic clusters, or, closely apposed to dendrites of granule and pyramidal cells.

Animals↗
PubMed1980

Suprachiasmatic nucleus, secondary synchronizing stimuli and the central neural control of circadian rhythms.

The introduction of a secondary synchronizing stimulus, deprivation of water for 22 h each day, with water available during the morning only, to intact adult female rats produces a burst of activity and drinking behavior during and around the time water is available. Normal circadian rhythms in activity and drinking behavior persist through the deprivation period, however, and the morning burst of activity and drinking behavior ceases with the cessation of deprivation schedule. These data indicate that the induced rhythm in activity and drinking behavior is a diurnal, not a circadian rhythm. This view is supported by the fact that a free-running circadian rhythm in activity and drinking behavior persists through a separate period of introduction of the water deprivation schedule even though a diurnal rhythm is once again induced. Suprachiasmatic nucleus ablation abolishes circadian rhythms in activity, drinking and learned behavior, but does not alter the deprivation schedule-induced rhythms.

Animals↗
PubMed1980

Immunoreactive calcitonin in the rat anterior pituitary gland and its localization in thyrotrophs.

The distribution of those cells in the anterior pituitary gland of the rat which stain immunohistochemically with rabbit anti-human calcitonin serum has been examined. Immunoreactive cells were confined primarily to the ventral surface of the gland and possessed both a distribution and morphology distinct from the corticotrophs. Staining of serial thin sections with rabbit anti-rat TSH-subunit serum resulted in an immunoreaction in those cells that stained for calcitonin. However, not all the thyrotrophs gave a positive immunoreaction for calcitonin. It is concluded from this study that it is inappropriate to attribute calcitonin as being part of the 31K-dalton precursor for adrenocorticotropin, a hypothesis that was proposed earlier. In the immunohistochemical reaction with anti-calcitonin serum, it was found that relatively high concentrations of antigen (500 micrograms/ml) were required in absorption experiments in order to inhibit staining. Furthermore, the staining of thyrotrophs with the anti-calcitonin serum was inhibited after preadsorption of the primary antiserum with excess rat beta-TSH (1000 micrograms/ml). Because of these immunochemical characteristics, it is questionable whether the calcitonin-like material observed in the rat pituitary gland is chemically identical to that of thyroidal calcitonin.

Animals↗
PubMed1980

Norepinephrine innervation of the cochlear nuclei by locus coeruleus neurons in the rat.

The cochlear nuclei (CN) contain a moderate concentration of norepinephrine (445 +/- 20 ng/g tissue) with dopamine levels (46 +/- 14 ng/g) that are low and within the precursor range expected for a norepinephrine (NE) terminal system. Lesion and horseradish peroxidase (HRP) experiments indicate that this innervation is bilateral and arises from fusiform and multipolar neurons in the locus coeruleus. Autoradiographic and fluorescence histochemical experiments demonstate that locus coeruleus fibers reach the ipsilateral ventral cochlear nuclei via a rostral pathway that projects from the rostral locus coeruleus laterally through the brain stem to the rostral tip of the ventral nuclei. This pathway is located dorsal to the motor and spinal trigeminal nuclei and ventral to the middle cerebellar peduncle. Descending coeruleo-cochlear fibers travel between the fourth ventricle and the vestibular nuclei to enter the acoustic striae. These fibers innervate both the dorsal and ventral nuclei. Contralateral locus fibers reach the CN by crossing in the pontine central gray at the rostral border of the fourth ventricle and by decussating with the fibers of the mesencephalic trigeminal nucleus ventral to the medial longitudinal fasciculus. The bilateral locus coeruleus innervation of the cochlear nuclei comprises a highly collateralized network of varicose axons which are not topographically organized. Unlike the cochlear nerve fibers in the CN which form specific projections, the locus coeruleus afferents to these sensory nuclei are diffuse and non-specific.

Animals↗