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R Y Moore

Publications and source records attributed to R Y Moore.

At least 163 records · Page 9Linked to original sources
PubMed1978

Serotonin neurons of the midbrain raphe: ascending projections.

The ascending projections of serotonin neurons of the midbrain raphe were analyzed in the rat using the autoradiographic tracing method. Axons of raphe serotonin neurons ascend in the ventral tegmental area and enter the medial forebrain bundle. A number of fibers leave the major group to ascend along the fasciculus retroflexus. Some fibers enter the habenula but the majority turn rostrally in the internal medullary lamina of the thalamus to innervate dorsal thalamus. Two additional large projections leave the medial forebrain bundle in the hypothalamus; the ansa peduncularis-ventral amygdaloid bundle system turns laterally through the internal capsule into the striatal complex, amygdala and the external capsule to reach lateral and posterior cortex, and another system of fibers turns medially to innervate medial hypothalamus and median eminence and form a contrelateral projection via the supraoptic commissures. Rostrally the major group in the medial forebrain bundle divides into several components: fibers entering the stria medullaris to terminate in thalamus; fibers entering the stria terminalis to terminate in the amygdala; fibers traversing the fornix to the hippocampus; fibers running through septum to enter the cingulum and terminate in dorsal and medial cortex and in hippocampus; fibers entering the external capsule to innervate rostral and lateral cortex; and fibers continuing forward in the medial olfactory stria to terminate in the anterior olfactory nucleus and olfactory bulb.

5,6-Dihydroxytryptamine↗
PubMed1978

Catecholamine innervation of the basal forebrain. II. Amygdala, suprarhinal cortex and entorhinal cortex.

The catecholamine (CA) innervation of the posterior basal forebrain, the amygdala, suprarhinal cortex and entorhinal cortex, was studied in the rat using biochemical assay and fluorescence histochemistry. The assay studies demonstrate a moderate norepinephrine (NE) content in the amygdala and entorhinal cortex with a lower value for the suprarhinal cortex. Following destruction of the locus coeruleus, the decrease in NE content of these basal forebrain structures indicates that their principal NE innervation is from locus coeruleus. An additional small NE input arises from the medullary NE neuron groups. Ablation of dopamine (DA) cell groups (substantia nigra-ventral tegmental area, SN-VTA) indicates that the DA input to the amygdala arises from the lateral VTA and medial half of the SN. Fluorescence histochemical studies using the glyoxylic acid-Vibratome technique demonstrate the presence of four distinct types of CA neuron terminal plexus in the posterior basal forebrain. These include two different DA fiber types arising in SN-VTA, small NE fibers with small varicosities arising in locus coeruleus and NE fibers with larger varicosities arising in other brainstem NE cell groups. The large NE fibers appear to enter the amygdala via the ansa peduncularis-ventral amygdaloid bundle to innervate the central and basolateral nucleus and the anterior amygdaloid area. The locus coeruleus NE fibers appear to enter the posterior basal forebrain via both the stria terminalis and ansa peduncularis-ventral amygdaloid bundle system to form a moderately dense innervation of the central and basolateral nuclei of the amygdala and a less dense innervation of the other areas. The DA neuron axons are concentrated in the central and basal nuclei and intercalated cell groups. Other areas receive a more diffuse DA input, with the exception of the moderately dense innervation of the suprarhinal cortex and DA "islands" in the ventral-anterrior entorhinal cortex, The DA input to the posterior basal forebrain is complex and heterogeneous and the axonal morphology differs greatly among the terminal fields within the amygdala and adjacent cortical areas.

Amygdala↗
PubMed1978

Catecholamine innervation of the basal forebrain. III. Olfactory bulb, anterior olfactory nuclei, olfactory tubercle and piriform cortex.

The catecholamine innervation of the olfactory bulb, anterior olfactory nuclei, olfactory tubercle and piriform cortex was studied in the rat using biochemical analysis and fluorescence histochemistry. Biochemical studies demonstrate a moderate norepinephrine (NE) content in all olfactory structures, a high dopamine (DA) content in the olfactory tubercle and a low DA content in the olfactory bulb, anterior olfactory nucleus and piriform cortex. Following locus coeruleus lesions NE content decreases 71% in the olfactory bulb, 82% in the anterior olfactory nucleus, 62% in olfactory tubercle and 77% in piriform cortex...

Amygdala↗
PubMed1978

Catecholamine innervation of the basal forebrain. IV. Topography of the dopamine projection to the basal forebrain and neostriatum.

In this study the location of dopamine (DA) neuron perikarya in the rostral mesencephalon of the rat was determined using the glyoxylic acid fluorescence histochemical technique. Subsequently the topography of the projection of these mesencephalic neurons on the basal forebrain and striatum was analyzed using the anterograde transport-autoradiographic tracing method and the retrograde transport-horseradish peroxidase (HRP) technique. The results of these anatomical studies were correlated with the biochemical and histochemical studies presented in previous reports (Moore, '78; Fallon and Moore, '78; Fallon et al., '78) to provide the following conclusions. The topography of the DA neuron projection of the basal forebrain and neostriatum is organized in three planes, dorsal-ventral, medial-lateral and anterior-posterior. DA cells are found almost exclusively in the substantia nigra (SN) and ventral tegmental area (VTA). Ventral cells of the SN and VTA project to the dorsal structures of the basal forebrain such as the septum, nucleus accumbens and neostriatum. The latter includes some DA cells located ventrally in the pars reticulata of the SN. Dorsal cells project to ventral structures. The medial-lateral topography is organized such that the medial sectors of the SN-VTA area project to the medial parts of nuclei in the basal forebrain and neostriatum whereas lateral sectors of the SN-VTA area project to the lateral parts of nuclei in the basal forebrain and neostriatum. An anterior-posterior topography also is evident such that anterior parts of the SN-VTA project anteriorly whereas the posterior SN-VTA projects more posteriorly in these areas. These observations are consistent with the view that the DA neurons of the SN-VTA complex form a single nuclear group with a highly topographically organized projection innervating not only deep nuclei of the telencephalon but allocortical structures as well.

Amygdala↗
PubMed1978

Noradrenaline neuron innervation of the neocortex in the rat.

Noradrenaline innervation of the rat neocortex is studied by glyoxylic acid histochemistry and radioisotopic biochemical analysis. The data indicate that all neocortical areas receive a noradrenergic innervation which is identical in organization but varies in density from area to area. Radioisotopic analysis of catecholamines in the cortical areas studied reveals only the presence of significant levels of noradrenaline. Unilateral locus coerulus ablation greatly diminishes ipsilateral noradrenaline content and fiber innervation in all neocortical areas studied. Detailed histochemical analysis reveals a diffuse plexus-like arrangement of noradrenaline fibers, with each cortical layer having a distinctive pattern of innervation. Single noradrenergic fibers enter layer VI of cortex and branch at all levels to undergo extensive collateralization. Terminal horizontal branching in the molecular layer results in the most dense fiber plexus of all cortical layers. This pattern of noradrenaline innervation is similar to that of other non-specific afferent systems innervating neocortex.

Animals↗
PubMed1978

Neonatal suprachiasmatic nucleus ablation: absence of functional and morphological plasticity.

Neonatal ablation of the suprachiasmatic nucleus in the rat has two important consequences. First, the direct projection from the retina to the suprachiasmatic nucleus fails to develop and no other retinal projection to any hypothalamic nucleus is formed. Second, circadian rhythms in drinking and spontaneous locomotor activity to not appear in these rats when they are tested as adults, and the females exhibit constant vaginal estrus. These observations indicate that the central neural mechanisms responsible for the generation and entrainment of circadian rhythmicity in the rat are not capable of either the functional or morphological plasticity characteristic of other developing neural systems.

Animals↗
PubMed1978

Demonstration by immunoperoxidase histochemistry of calcitonin in the anterior lobe of the rat pituitary.

We have demonstrated by a specific immunoperoxidase procedure the presence of calcitonin-containing cells in the rat pituitary gland. These cells are widely distributed throughout the anterior lobe and seem to constitute the entire population of cells of the intermediate lobe. No such cells were seen in the posterior lobe. The presence of calcitonin-containing cells in the pituitary provides novel implications about the physiological significance of this hormone.

Animals↗
PubMed1978

Neural control of pineal function in mammals and birds.

Pineal function in mammals is regulated by a system with four major neural components. The first is a retinohypothalamic projection from the ganglion cells of the retina to the suprachiasmatic nucleus of the hypthalamus. The suprachiasmatic nucleus appears to function as a circadian oscillating system projecting into the hypothalamus and this represents the second component. The third component is constituted of a brainstem pathway from the lateral hypothalamus to the intermediolateral cell column of the upper thoracic spinal cord. The fourth component is the preganglionic and postganglionic sympathetic system arising from the upper thoracic cord to innervate the superior cervical ganglion which, in turn, innervates the pineal gland. No direct neural control of the pineal gland has been demonstrated in birds.

Animals↗
PubMed1977

Ascending projections of the locus coeruleus in the rat. I. Axonal transport in central noradrenaline neurons.

Axonal transport of protein and metabolites of L-[3H(G)]3, 4-dihydroxyphenylalanine ([3H]DOPA) was studied in the central noradrenaline neurons of the pontine nucleus locus coeruleus and was correlated with regional alterations of noradrenaline content following destruction of the nucleus. Unilateral lesions of the locus coeruleus produce a partial depletion of noradrenaline in the ipsilateral hypothalamus and telencephalon, indicating that these neurons project widely to the ipsilateral forebrain. Twenty-four to 48 h following local injections of 50 micronCi [3H]proline, locus coeruleus neurons take up labeled material and transport it, presumably as protein, to ipsilateral structures in the midbrain, diencephalon and telencephalon including the neocortex. Similarly 8 h after injection of 25 micronCi [3H]DOPA into the locus coeruleus, transport of material including catecholamines occurs to ipsilateral diencephalon and telencephalon. Axonal transport of proteins to telencephalic structures is greatly diminished by selective lesions of catecholamine terminals with 6-hydroxydopamine (6-OHDA) and following destruction of the medial forebrain bundle. These results provide further support for the view that noradrenaline neurons of the locus coeruleus nucleus project widely within the neuraxis to ipsilateral structures of the brain stem, diencephalon and telencephalon, including all cortical areas. In addition, evidence is presented for a contralateral projection with a similar distribution. The rate of axonal transport of labeled protein and metabolites of [3H]DOPA including [3H]catecholamines in central noradrenaline neurons is estimated to be 3-4 mm/h and is accordingly similar to that reported for noradrenaline neurons of the peripheral sympathetic nervous system.

Adrenergic Fibers↗
PubMed1977

Ascending projections of the locus coeruleus in the rat. II. Autoradiographic study.

The ascending projections of the locus coeruleus were studied using an autoradiographic method. The major projection of locus coeruleus neurons ascends in a dorsal pathway traversing the midbrain tegmentum in a position ventrolateral to the periaqueductal gray. At the caudal diencephalon the locus coeruleus axons descend to enter the medial forebrain bundle at a caudal tuberal hypothalamic level. They are jointed in the medial forebrain bundle by a much smaller locus coeruleus projection which takes a ventral course through the midbrain tegmentum and enters the medial forebrain bundle via the mammillary peduncle and ventral tegmental area. Terminal projections are evident in the midbrain to the periaqueductal gray, tegmentum and raphe nuclei. There are widespread projections to the dorsal thalamus. The heaviest of these are to the intralaminar nuclei, the anteroventral and anteromedial nuclei, the dorsal lateral geniculate and the paraventricular nucleus. In the hypothalamus the largest projections are to the lateral hypothalamic area, periventricular nucleus, supraoptic nucleus and paraventricular nucleus. As the locus coeruleus projection ascends in the medial forebrain bundle, fibers leave it to traverse the lateral hypothalamus and zona incerta and enter the internal capsule, the ventral amygdaloid bundle and ansa peduncularis. These appear to terminate in the amygdaloid complex and, via the external capsule, in the lateral and dorsal neocortex. At the level of the septum 4 projections are evident. One group of fibers enters the stria medullaris to terminate in the paraventricular nucleus and habenular nuclei. A second group joins the stria terminalis to terminate in the anygdaloid complex. The third group turns into the diagonal band and medial septum; some fibers terminate in the septal nuclei and others continue into the fornix to termimate in hippocampus. A large component continues around the corpus callosum into the cingulum to terminate in the cingulate and adjacent neocortex, the subiculum and hippocampus. The remaining fibers continue rostrally in the medial forebrain bundle to terminate in olfactory forebrain and frontal neocortex. Commissural projections arise at 4 locations. The first decussation occurs in the dorsal tegmentum just below the central gray rostral to the locus coeruleus. The crossing fibers enter the contralateral dorsal bundle. A second group of fibers leaves the ipsilateral dorsal pathway, crosses in the posterior commissure and enters the contralateral dorsal pathway at the level. The third commissural projection arises more rostrally and crosses in the dorsal supraoptic commissure to enter the contralateral medial forebrain bundle. The fourth commissural projection is through the anterior commissure. The termination of the contralateral projection appears similar to that of the ipsilateral projection.

Afferent Pathways↗
PubMed1977

The lateral hypothalamic area. An ultrastructural analysis.

An ultrastructural analysis of the rat lateral hypothalamic area (LHA) was undertaken in order to provide an initial step in the characterization of this complex area which appears to participate in a number of important neural functions. The organization of the normal tuberal LHA was compared to the area following acute and chronic denervating lesions. In the normal animal, the principal features of the LHA are the presence of lateral hypothalamic neurons, a major sagittal pathway (the medial forebrain bundle, MFB) and the interposed neuropil richly populated by a variety of synaptic terminal types. Alterations in the synaptic organization of the LHA following rostral and caudal MFB lesions were most pronounced in animals with acute and chronic caudal lesions. A 10% reduction of synaptic terminals containing 800-1000 A diameter dense core vesicles and a 10% increase in terminals containing lucent core vesicles was observed in animals with caudal lesions while no significant redistribution of synaptic terminal types occurred with rostral lesions. The preliminary degeneration experiments indicate that identification of the numerous and diverse afferents to the LHA neuropil may be aided by this method but that a detailed and systematic ultrastructural analysis will be required to identify sources of input with certainty.

Animals↗
PubMed1977

Postnatal development of the suprachiasmatic hypothalamic nucleus of the rat.

Light and electron microscopy of newborn, four day, one, two, three and five week old rats revealed principally a progressive increase in the diversity and number of synaptic contacts in the suprachiasmatic nucleus (SCN). The major increase in synaptic diversity occurred between four days and one week of age. Correlation between this finding and the adult synaptic morphology of SCN (Gülder, 1976) on the one hand, and the ontogeny of circadian rhythms on the other were made. This suggested that the retinal afferents arriving on day four form asymmetrical contacts with dendrites. While increase in synaptic number was progressive, it was most marked between three and five weeks of age. By five weeks, most features of the adult SCN were present. No significant morphological effects were evident as a result of neonatal retinal lesions.

Animals↗