Search PubMed⌕ Search

Biomedical subjects

Y Shiotani

Publications and source records attributed to Y Shiotani.

At least 37 records · Page 2Linked to original sources

Neurotensin-containing projections from the retrosplenial cortex to the anterior ventral thalamic nucleus in the rat.

The neurotensin-containing projections from the retrosplenial cortex to the anterior ventral thalamus were demonstrated by electrolytic lesion studies and fluorescent retrograde tracing combined with immunocytochemistry. Three-to-five-day-old rats were used, because the immunoreactivity of neurotensin fibers in anterior ventral thalamus was the highest at this age. When neurotensin-containing neurons located in layer VI of the retrosplenial cortex were unilaterally destroyed by applying an electrolytic current to the retrosplenial area, the neurotensin fibers in the ipsilateral anterior ventral thalamus decreased dramatically. Unilateral injection of a fluorescent retrograde tracer, Fast Blue, into the anterior ventral thalamus, labeled neurons in the ipsilateral retrosplenial cortex, and many of these cells also had neurotensin-like immunoreactivity. These results suggested that a major origin of the neurotensin fibers in the anterior ventral thalamus was in the ipsilateral retrosplenial granular cortex.

Amidines↗

Coexistence of substance P- and enkephalin-like peptides in single neurons of the rat hypothalamus.

The distribution of substance P- and enkephalin-like immunoreactivity in single cells were examined by the double immunofluorescence method. Substance P- and leucine-enkephalin-like compounds coexisted within individual neurons of some hypothalamic areas such as the medial preoptic area, anterior hypothalamic area, perifornical area, lateral hypothalamic area, premammillary nuclei and posterior hypothalamic nucleus, although they did not coexist in the majority of immunoreactive cells.

Animals↗

The histaminergic innervation of the mesencephalic nucleus of the trigeminal nerve in rat brain: a light and electron microscopical study.

Histaminergic fibers in the mesencephalic nucleus of the trigeminal nerve of Long-Evans rats were examined by light and electron microscopy after peroxidase-antiperoxidase immunocytochemical staining for histidine decarboxylase (HDC) as a marker. By light microscopy, neurons in the mesencephalic nucleus of the trigeminal nerve were seen to be surrounded by a number of HDC-like immunoreactive (HDCI) fibers, suggesting the presence of axo-somatic contact. This finding was supported by immunoelectron microscopic demonstration of synaptic contact of some HDCI fibers with the soma of the neurons in this nucleus. These findings indicate that histamine is involved in the sensory regulation of movement of the masticatory muscles at the level of the trigeminal mesencephalic nucleus.

Animals↗

[Radioimmunoassay of the calcitonin gene-related peptide and its measurement in the plasma of patients with medullary thyroid carcinoma and in the cerebrospinal fluid of normal subjects].

Calcitonin gene-related peptide (CGRP) is a peptide recently found by recombinant DNA and molecular biological techniques in rat medullary thyroid carcinoma cells, but its physiological role(s) is unknown. We established a radioimmunoassay for this peptide using human-CGRP (1-37) as a standard, 125I-human-CGRP (1-37) as a tracer, and anti-rat-CGRP (28-37) serum as a first antibody. Aprotinin, an inhibitor of proteolytic enzymes in the plasma, was also added to the assay system, because in its absence the tracer was degraded during incubation with plasma samples. The sensitivity of the assay was 60 pg/ml and the intra- and inter-assay coefficients of variation were 6.0% and 8.5%, respectively. The recovery was 105 +/- 17%. The plasma levels of CGRP in 17 normal subjects (mean +/- S.D. age, 45 +/- 12 years) were all below 300 pg/ml, the mean level being 132 +/- 77 pg/ml. The levels were also below 300 pg/ml in 20 of 21 patients with medullary thyroid carcinoma, but one patient who had a high level of 942 pg/ml (mean value, 142 +/- 193 pg/ml). There was no significant difference between the mean plasma levels of CGRP in normal subjects and patients with medullary thyroid carcinoma. The mean plasma levels of CGRP in 5 patients with medullary thyroid carcinoma did not increase in response to infusion of either 4.3 mg/kg of calcium in 10 minutes or 4 micrograms/kg of tetragastrin in 5 minutes, although the plasma levels of calcitonin in these patients increased markedly during these provocation tests. The levels of CGRP in the cerebrospinal fluid of 16 normal volunteers were all below the detectable limit (less than 60 pg/ml). These findings suggest that fewer patients with medullary thyroid carcinoma than reported previously have high plasma levels of CGRP, either in the basal state or in response to calcium or gastrin, and that the levels of CGRP in the cerebrospinal fluid of normal subjects are very low.

Adolescent↗

Hippocampofugal gamma-aminobutyric acid (GABA)-containing neuron system in the rat: a study using a double-labeling method that combines retrograde tracing and immunocytochemistry.

Using a double-labeling method that combines retrograde tracing and immunocytochemistry, we demonstrated the presence of a hippocampofugal gamma-aminobutyric acid (GABA)-like immunoreactive (GABA-LI) neuron system in the rat. As a preliminary experiment, knife-cut of the dorsal fornix was made and it resulted in a remarkable accumulation of GABA-LI fibers caudal to the section. This suggested the presence of a hippocampofugal GABAergic projection. The hypothesis was confirmed by the double-labeling method: injection of the biotinylated wheat germ agglutinin (B-WGA) into the septum resulted in labeling numerous neurons in the hippocampus and some of them also showed GABA-like immunoreactivity by the simultaneous immunostaining with the antiserum against GABA.

Animals↗

Distribution and origin of calcitonin gene-related peptide in the rat stomach and duodenum: an immunocytochemical analysis.

We studied the three-dimensional distribution of structures with calcitonin gene-related peptide-like immunoreactivity (CGRPI) in the rat stomach and duodenum, including the origins of these structures, using indirect immunofluorescence in both muscle strips and frozen sections. There was a very dense meshwork of CGRPI fibers in the circular and longitudinal muscle layers, and also in the myenteric and submucous plexuses of the stomach and duodenum. No CGRPI neurons were seen in the stomach, even in rats treated with colchicine; in the duodenum, there was a group of CGRPI cells in the myenteric and submucous ganglia. No regional differences were seen in the stomach and duodenum. We found by experimental manipulations that CGRPI fibers in the stomach were exclusively extrinsic in origin; some of such fibers in the duodenum were intrinsic in origin, though most were supplied by CGRPI cells outside the duodenum.

Animals↗

Distribution and origins of substance P (SP)-, calcitonin gene-related peptide (CGRP)-, vasoactive intestinal polypeptide (VIP)- and neuropeptide Y (NPY)-containing nerve fibers in the pineal gland of gerbils.

In the pineal gland of gerbils, substance P (SP)-, calcitonin gene-related peptide (CGRP)-, vasoactive intestinal polypeptide (VIP)- and neuropeptide Y (NPY)-containing nerve fibers were demonstrated immunohistochemically. After intrapineal injection of biotin-wheat germ agglutinin, origins of fibers were examined by the combined technique of tracing method and immunohistochemistry. It was confirmed that SP- and CGRP-fibers originated from the trigeminal ganglion, VIP-fibers from the pterygopalatine ganglion and NPY-fibers from the superior cervical ganglion.

Animals↗

Distribution of calcitonin gene-related peptide-containing fibers in the urinary bladder of the rat and their origin.

By use of indirect immunofluorescence, this study demonstrated the presence of calcitonin gene-related peptide-like immunoreactive (CGRPI) fibers in the bladder of the rat. These fibers were abundant in the muscle layer, in which they ran parallel to the muscles, submucosa, and epithelium. No immunoreactive cells were detected. We also examined the origins of these fibers, using a method that combined biotinized retrograde tracer (biotin-wheat germ agglutinin) (B-WGA) and immunocytochemistry. Injection of the tracer into the bladder resulted in the demonstration of small to medium-sized labeled cells that contain CGRPI structures in single dorsal root ganglion cells mostly at the level of L6 and S1, but also a few at L2. Double-staining for CGRPI and immunoreactive P-like substance (SPI) indicated that there are cells in the dorsal root ganglia at the level of L6 and S1 that react to both, but that there are many CGRPI-positive cells that contain no demonstrable SPI; most of the latter are large.

Animals↗

Effect of calcitonin gene-related peptide on contraction of striated muscle in the mouse.

We have found ultrastructurally calcitonin gene-related peptide-like immunoreactivity in the axon terminal within the synaptic trough of neuromuscular junction of the mouse. We determined, using pharmacological means, with a phrenic nerve-diaphragm preparation, that this peptide enhances muscle contraction during stimulation of the nerve fibers or direct stimulation of the muscle. This effect is probably brought about via the receptor for this peptide not the acetylcholine receptor.

Animals↗

Peptidergic and aminergic innervation of the facial nucleus of the rat with special reference to ontogenetic development.

The distribution and ontogenetic development of several neuropeptides such as enkephalin, substance P, somatostatin, neuropeptide Y, and of monoamines such as serotonin and catecholamines in the facial nucleus of the rat were investigated with immunocytochemistry. The neuropeptides were concentrated in certain subnuclei. Enkephalin-immunoreactive fibers were distributed in the medial and dorsal subnuclei, substance P in the intermediate and dorsal subnuclei, somatostatin in the intermediate subnucleus, and neuropeptide Y in the dorsal subnucleus. The amines were distributed evenly throughout the nucleus. These distribution patterns suggest that peptidergic fibers are closely related to the functions of different subnuclei, while fibers containing monoamines are more basic--not specific to individual muscles. Few of these fibers were observed in the prenatal stage of the rat, but they increased markedly in number during the first postnatal week, and had established their innervation pattern by the tenth postnatal day, which coincides with the establishment of nerve-muscle innervation. The present study further showed that fibers containing serotonin are supplied mainly from the raphe nucleus, that catecholamine fibers are from neurons containing catecholamine surrounding the facial nucleus, and that fibers containing neuropeptide Y are from the lateral part of the caudal medullary reticular formation. These findings suggest that catecholamine and neuropeptide Y are not both present in the single neurons projecting to the facial nucleus.

Animals↗

Ultrastructural evidence of direct synaptic contact of catecholamine terminals with oxytocin-containing neurons in the parvocellular portion of the rat hypothalamic paraventricular nucleus.

Ultrastructural evidence of the direct interaction between catecholamine (CA) terminals and oxytocin (OX)-containing neurons in the parvocellular portion of the rat hypothalamic paraventricular nucleus was demonstrated using immunohistochemistry combined with false transmitter (5-hydroxydopamine, 5-OHDA) histochemistry. At the parvocellular portion, 5-OHDA labelled CA terminals make synaptic contact with proximal dendrites or somas of OX-positive cells, suggesting that the ascending CA system monosynaptically regulates the extrahypothalamic OX system.

Animals↗

An arcuato-paraventricular and -dorsomedial hypothalamic neuropeptide Y-containing system which lacks noradrenaline in the rat.

The origins of neuropeptide Y-like immunoreactive (NPYI) fibers in the paraventricular and dorsomedial hypothalamic nuclei of the rat were examined using immunohistochemistry. Destruction of the arcuate nucleus resulted in a marked decrease of NPYI fibers ipsilaterally in these nuclei, suggesting that most of NPYI fibers in these nuclei originate from NPYI neurons in the arcuate nucleus. These NPYI systems did not contain noradrenalin.

Animals↗

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↗

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↗

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↗

Neuropeptides and gamma-aminobutyric acid in the vestibular nuclei of the rat: an immunohistochemical analysis. I. Distribution.

The distribution of substance P, Leu-enkephalin and gamma-aminobutyric acid (GABA) containing structures in the rat vestibular nuclei were investigated by means of an indirect immunofluorescent method using specific antisera to substance P, Leu-enkephalin and glutamic acid decarboxylase (GAD), respectively. Numerous positive neurons and fibers containing these three substances were found in the medial vestibular nucleus. Most of them were situated in the caudal part of the nucleus and those in the rostral part were concentrated dorsally. In the descending vestibular nucleus, a large number of substance P, Leu-enkephalin and GAD containing neurons were evenly distributed among longitudinally directing fiber bundles. A number of positive fibers with these substances were also observed. The lateral vestibular nucleus contained numerous coarse GAD-immunoreactive fibers surrounding Deiters' neurons, while substance P-immunoreactive and Leu-enkephalin-immunoreactive fibers were rather poorly distributed in this nucleus as well as in the superior vestibular nucleus.

Animals↗