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Biomedical subjects

M Tohyama

Publications and source records attributed to M Tohyama.

At least 469 records · Page 26Linked to original sources
PubMed1985

Immunohistochemical evidence for the coexistence of calcitonin gene-related peptide- and choline acetyltransferase-like immunoreactivity in neurons of the rat hypoglossal, facial and ambiguus nuclei.

The present immunocytochemical study demonstrates that calcitonin gene-related peptide-like immunoreactivity (CGRPI) coexists with acetylcholine in single cells of hypoglossal, facial and ambiguus nuclei. The experiments were done using alternate frozen sections from relevant regions of the rat brain. We further show that CGRPI is localized in the nerve terminals that form neuromuscular junctions in the tongue muscles.

Animals↗
PubMed1985

Occurrence of calcitonin gene-related peptide in the chicken amacrine cells.

The distribution of calcitonin gene-related peptide (CGRP)-like immunoreactivity (CGRPI) in the chicken retina was investigated by means of immunohistochemistry. CGRPI was localized in the stratified amacrine cells. The terminal branching pattern of these cells was different between the central and peripheral retinal regions. Flat-mount preparations revealed these CGRPI cells to be evenly distributed in the entire retina with surprisingly rich arborization.

Animals↗
PubMed1985

Somatostatinergic neurons in the insular cortex project to the spinal cord: combined retrograde axonal transport and immunohistochemical study.

A double-labeling method combining immunohistochemistry and a retrograde tracer technique using biotin-horseradish peroxidase (B-HRP) was employed to identify a descending somatostatinergic fiber system from the insular cortex to the spinal cord. Injection of B-HRP into the spinal cord at cervical or lumbar levels resulted in the labeling of a number of neurons in the insular cortex. Simultaneous immunostaining revealed the existence of double-labeled neurons in the insular cortex. The result provides direct evidence for the presence of a descending somatostatinergic pathway from the insular cortex to lumbar levels of the spinal cord.

Animals↗
PubMed1985

Immunocytochemical localizations of cytosolic and mitochondrial glutamic oxaloacetic transaminase isozymes in rat retina as markers for the glutamate-aspartate neuronal system.

The localization of cytosolic (s) or mitochondrial (m) glutamic oxaloacetic transaminase (GOT) was examined in the rat retina by means of an indirect immunofluorescence method using antibodies specific for s- and m-GOT. The m-GOT-like immunoreactive structures were seen on the inner segments of the photoreceptor cells and other outer and inner plexiform layers. These structures were dot-like in appearance. Somas were not labeled. In contrast, s-GOT-like structures were found on the inner segments and inner fibers of the photoreceptor cells, numerous cell somas in the inner nuclear layer (horizontal, amacrine and bipolar cells), and ganglion cell layer (displaced amacrine cells) and inner plexiform layer. The difference in distribution between s- and m-GOT isozymes suggests that they may be useful as markers for glutamatergic and/or aspartinergic neurons.

Animals↗
PubMed1985

Leucine-enkephalin-like immunoreactive fibers in the medial preoptic area of the rat: their distribution and origin.

We studied the distribution of fibers with leucine-enkephalin-like immunoreactivity (L-ENKI) in the medial preoptic area (MPO) of the rat, and the origins of such fibers, using indirect immunofluorescence and a combination of a retrograde tracer with immunocytochemistry that we have developed. These fibers were very dense throughout the rostro-caudal part of the MPO. The distribution was uneven with the highest density in the lateral part. Destruction of the arcuate nucleus, which contains a group of L-ENKI neurons, resulted in the marked reduction of these fibers in the ipsilateral MPO, suggesting that most of these fibers originate in this nucleus. This was also suggested by the fact that injection of biotin-wheat germ agglutinin into the MPO labelled many neurons in the arcuate nucleus ipsilaterally. Simultaneous staining with antiserum showed that some of these neurons are L-ENKI.

Animals↗
PubMed1985

Origin and fine structure of substance P-containing nerve terminals in the facial nucleus of the rat: an immunohistochemical study.

The distribution, origin and fine structure of substance P-like immunoreactive (SPI) nerve terminals in the facial nucleus of the rat were investigated by means of immunocytochemistry. SPI-terminals were concentrated in the intermediate and dorsal subnuclei of the facial nucleus. Hemi-transection of the brainstem just rostral to the facial nucleus or at the most caudal level of the medulla oblongata did not cause any change of SPI-terminals in the facial nucleus. Electrical destruction of the various parts of the medulla oblongata clearly demonstrated that SPI-terminals in the intermediate subnucleus were supplied contralaterally from the SPI-neurons in the dorsomedial part of the medullary reticular formation. Most of the SPI-terminals (85%) in the intermediate subnucleus of the facial nucleus were observed to make asymmetric synaptic contacts with large dendrites (mean diameter; 1.26 micron). It was supposed that the contact sites are located on proximal parts of the dendrite. A few SPI-terminals (6%) formed axo-somatic contacts with large perikarya filled with numerous cytoplasmic organelles.

Animals↗
PubMed1985

Three-dimensional distribution of substance P-like immunoreactivity in the urinary bladder of rat.

The overall distribution of substance P-like immunoreactive (SPI) fibers in the rat urinary bladder was examined by means of frozen sections and whole mount preparations. Two types of SPI fibers entered the urinary bladder from the neck; one forming thick fiber bundles and the other around the blood vessels. These SPI fiber bundles branched into several thinner segments which often project many collaterals to the smooth muscle and submucosal layers. In the smooth muscle layer, single SPI fibers were seen running parallel to both longitudinal and circular muscle bundles. They appeared to be evenly distributed in the smooth muscle layer. SPI fiber bundles located in the circular muscle layer dissociated SPI fibers which entered the submucosal layer, where they directed to the epithelium and formed a meshwork just beneath it. SPI fibers often left the meshwork to enter the epithelium where abundant arborization of fine SPI fibers was seen. The density of SPI fibers in the submucosal layer and epithelium was not even. The highest density was identified in the neck and the trigonum area.

Animals↗
PubMed1985

Neuropeptide Y-like immunoreactive structures in the rat stomach with special reference to the noradrenaline neuron system.

The origins and overall distribution of neuropeptide Y-like immunoreactive (NPYI) structures in the rat stomach were investigated by immunofluorescent staining of muscle strips from rats subjected to chemical and surgical neurotomy. The present study has demonstrated that the majority of NPYI fibers in the myenteric plexus and along the blood vessels in the muscle layers originate from NPYI cell bodies located in the celiac ganglion, which also contains noradrenaline. The remaining NPYI fibers in the circular and longitudinal muscle layer and a small number of NPYI fibers in the myenteric plexus do not contain noradrenaline and are of intrinsic origin. Noradrenaline fibers in the muscle layer are not associated with blood vessels. They originate from the celiac ganglion but do not contain NPYI structures.

Animals↗
PubMed1985

Adrenorphin immunoreactivity in rat brain.

Adrenorphin is the first C-terminally amidated form of opioid peptides isolated from human pheochromocytoma tumor and is considered to be generated out of proenkephalin A by unique processing. By the highly specific and sensitive radioimmunoassay (RIA) procedure utilizing the antiserum against adrenorphin, combined with high performance liquid chromatography (HPLC), immunoreactive adrenorphin in rat brain was verified to be identical with its authentic peptide. It has been revealed that adrenorphin immunoreactivity distributes widely in rat brain but in the unique pattern distinct from those of other endogenous opioid peptides. Note that immunoreactive adrenorphin was most concentrated in the olfactory bulb, and appreciably in the hypothalamus and striatum. Furthermore, immunohistochemical study has revealed that adrenorphin-immunoreactive structures in hypothalamic region of rat were localized in the neurones of the arcuate nucleus. In addition, adrenorphin-immunoreactive fibre plexus was found in the various regions of the hypothalamus, such as median eminence, periventricular zone and paraventricular nucleus. These indicate that adrenorphin may have a unique physiological function.

Animals↗
PubMed1985

Ontogeny of visinin-like immunoreactive structures in the rat cerebellum and vestibular nuclei: an immunohistochemical analysis.

The ontogeny of visinin-like immunoreactive (visinin-IR) structures in the cerebellum and vestibular nuclei of the rat brain was examined by indirect immunofluorescence. Visinin-IR structures are localized exclusively in the Purkinje cell system in these areas. Immunoreactive Purkinje cells first appear at gestational day 18, increasing in number with age. The axons appear at gestational day 19 and develop markedly until reaching the adult level at postnatal day 4. However, immunoreactive dendrites do not reach the adult pattern until postnatal day 21. In the cerebellar and vestibular nuclei, immunoreactive fibers first appeared at gestational day 18 and increased in number there with age, reaching the adult level at postnatal day 4.

Animals↗
PubMed1985

Ontogeny of substance P-containing fibers in the taste buds and the surrounding epithelium. I. Light microscopic analysis.

Ontogeny of the substance P-like immunoreactive (SPI) structures in the circumvallate papillae of the rat taste buds was examined by means of indirect immunofluorescence method. SPI fibers in the lamina propria first appeared at gestational day 20, and their quantity increased up to postnatal day 10. On the other hand, SPI fibers in the epithelium were first seen on gestational day 21 and in the taste buds at postnatal day 2-4. These fibers increased remarkably in number after postnatal day 5 and reaching their maximum at postnatal day 20, and thereafter numbers decreasing slightly.

Animals↗
PubMed1985

Co-existence of glucagon- and substance P-like immunoreactivity in the chicken retina.

This immunohistochemical study of chicken retina using flat-mounts shows that pancreatic glucagon- and substance P-like immunoreactive amacrine cells have more heterogeneous subpopulations than was previously understood to be the case. Using double-staining immunohistochemical procedures we demonstrate that a substantial proportion of all subtypes of glucagon-like immunoreactive cells contain substance P-like immunoreactivity and that the ratio of the amacrine cells containing both peptides to total immunoreactive cells varies according to position in the retinal and cell type. These results suggest that retinal cells may have different functions according to position or cell type.

Animals↗
PubMed1985

Localization of chick retinal visinin-like immunoreactivity in the rat forebrain and diencephalon.

The present study is an examination, using an indirect immunofluorescence method, of the distribution of visinin, a 24,000 dalton peptide, in the rat forebrain and diencephalon. Immunoreactive structures were localized in the neuronal elements showing an uneven distribution. Immunoreactive neurons were found in the olfactory bulb, anterior olfactory nucleus, cerebral cortex, amygdaloid complex, ventral portion of the nucleus caudatus putamen, septal area, nucleus accumbens, nucleus paratenialis, nucleus rhomboideus, nucleus reuniens, nucleus paraventricularis hypothalami, nucleus supraopticus, nucleus anterior hypothalami, preoptic area, hypothalamic periventricular nucleus, nucleus mammillaris medialis, medial habenular nucleus, zona incerta, nucleus lateralis thalami, nucleus tractus optici and gyrus dentatus. Immunoreactive fibers were observed in the above areas, particularly near the labelled cells, forming fiber plexuses of varying density. In addition, dense plexuses were also seen in the globus pallidus, anteroventral nucleus of the thalamus, substantia nigra and hippocampus. In the former three structures, no labelled cells were present and in the latter, a few scattered neurons were found, indicating that these fibers originate from extrinsic sources.

Animals↗
PubMed1985

Topographic localization of calcitonin gene-related peptide in the rat brain: an immunohistochemical analysis.

The distribution of immunoreactive calcitonin gene-related peptide in the rat brain was investigated by means of an indirect immunofluorescence method. In addition to previously reported calcitonin gene-related peptide-like immunoreactive structure-containing sites such as the nucleus ambiguus, nucleus originis nervi facialis, nucleus originis nervi hypoglossi, nucleus peripeduncularis and nucleus parabrachialis, the present study demonstrated a far wider distribution of calcitonin gene-related peptide-like immunoreactive structure-containing cells in the rat brain, i.e. the nucleus hypothalamicus lateralis, nucleus ventromedialis thalami, colliculus superior, lemniscus lateralis, gyrus dentatus, nucleus olivaris superior, nucleus tractus solitarii, nucleus cuneiformis, nucleus parabigeminalis and a proportion of the Purkinje cells. We have also demonstrated a more extensive network of calcitonin gene-related peptide-like immunoreactive fibers distributed in various areas throughout the rat brain than has been reported previously such as the colliculus inferior, nucleus olivaris superior, nucleus vestibularis lateralis and inferioris, and nucleus cochlearis dorsalis and ventralis, etc.

Animals↗
PubMed1985

Distribution, ontogeny and projections of cholecystokinin-8, vasoactive intestinal polypeptide and gamma-aminobutyrate-containing neuron systems in the rat spinal cord: an immunohistochemical analysis.

The distribution, ontogeny and fiber projections of cholecystokinin-8, vasoactive intestinal polypeptide and gamma-aminobutyrate-containing neuronal systems in the rat spinal cord were investigated by means of immunocytochemistry. Immunoreactive fibers to cholecystokinin-8, vasoactive intestinal polypeptide and glutamate decarboxylase (gamma-aminobutyrate-synthesizing enzyme, used as a marker of gamma-aminobutyrate) were widely distributed in the spinal cord, being particularly concentrated in the superficial dorsal horn, suggesting a close relationship to the pain transmission system. Cholecystokinin-8-containing neurons were mostly distributed in the dorsal laminae and glutamate decarboxylase-containing neurons were distributed in both the dorsal and ventral horns. Vasoactive intestinal polypeptide-containing neurons were detected in the lateral spinal nucleus and the lamina X. Cholecystokinin-8 and vasoactive intestinal polypeptide immunoreactive structures first appeared on gestational day 17-18. Although no substantial change in immunoreactive structures was observed during the fetal period, they increased markedly after birth. On the other hand, glutamate decarboxylase-positive structures appeared at gestational day 16 and those in the grey matter reached a maximum content at birth; both groups were present in adult animals. Transection of the upper cervical cord resulted in accumulations of cholecystokinin-8 and glutamate decarboxylase rostral to the lesion, revealing the presence of supraspinal projections of cholecystokinin-8 and glutamate decarboxylase to the spinal cord. The same experimental procedure demonstrated the existence of vasoactive intestinal polypeptide-mediating neuronal projections to the supraspinal level, as the accumulating fibers occurred in the area caudal to the lesion.

Animals↗
PubMed1985

Calcitonin gene-related peptidergic projection from the parabrachial area to the forebrain and diencephalon in the rat: an immunohistochemical analysis.

We investigated ascending fiber projections of calcitonin gene-related peptide from the parabrachial area to the forebrain and diencephalon in the rat using immunocytochemistry. Destruction of the lateral portion of the dorsal parabrachial area resulted in a marked ipsilateral decrease in the fibers containing calcitonin gene-related peptide in the ventromedial hypothalamic nucleus, indicating that cells containing calcitonin gene-related peptide in the lateral portion of the dorsal parabrachial area projected to the ipsilateral ventromedial hypothalamic nucleus. Destruction of the ventral portion of the parabrachial area resulted in a marked decrease of fibers containing calcitonin gene-related peptide in the bed nucleus of the stria terminalis, the central amygdaloid nucleus and the lateral hypothalamus just medial to the crus cerebri (the far-lateral hypothalamus), and a less marked decrease in the ventromedial thalamic nucleus. This means that there are projections from cells containing calcitonin gene-related peptide in the ventral portion of the parabrachial area to the first three regions just mentioned, and to some extent to the last.

Afferent Pathways↗
PubMed1985

Distribution of calcitonin gene-related peptide in the rat peripheral nervous system with reference to its coexistence with substance P.

This immunocytochemical study, using a double-staining method, showed that calcitonin gene-related peptide-like immunoreactive structures are widely distributed in the peripheral nervous system and that many of them coexist with substance P-like immunoreactive structures in single sensory ganglion cells. Neurons positive for calcitonin gene-related peptide but negative for substance P were detected in sensory ganglia. These cells were large (about 30-45 micron in diameter); these primary sensory neurons containing calcitonin gene-related peptide can probably act independently of substance P. There were neurons containing calcitonin gene-related peptide without substance P in the pterygopalatine ganglion, although these cells were less numerous than in the sensory ganglia. In consecutive sections, calcitonin gene-related peptide-like structures occurred in thyroid parafollicular cells, which also contain calcitonin. This suggested that messenger RNA for producing calcitonin gene-related peptide is also present in the thyroid, and like calcitonin, calcitonin gene-related peptide may have a peripheral physiological role.

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