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M Tohyama

Publications and source records attributed to M Tohyama.

At least 559 records · Page 31Linked to original sources
PubMed1982

Ontogeny of substance P-containing neuron system of the rat: immunohistochemical analysis--II. Lower brain stem.

Ontogeny of the substance P neuron system in the lower brain stem of the rat was investigated by means of the indirect immunofluorescence technique. Substance P-positive structures (cells and fibers) first appeared in the primordium of the ventral part of the nucleus tractus spinalis nervi trigemini (nVs), in the reticular formation between nucleus reticularis lateralis and nVs, and in the reticular formation between nVs and nucleus originis nervi facialis, respectively, at gestational day 14. After that time, substance P-positive structures made their appearance gradually in various areas of the lower brain stem. The present study demonstrates that substance P-positive structures appear at a very early ontogenetical stage, which suggests that substance P may play a role in the development of the lower brain stem in addition to its role as a neurotransmitter or neuromodulator.

Aging↗
PubMed1982

Localization of LH-RH immunoreactivity in the avian retina.

The present study demonstrated numerous LH-RH--positive structures in the paddy-bird (padda orizivora) retina. LH-RH-positive cells were seen in the ganglion cell layer (GL), inner plexiform layer (IPL) and inner nuclear layer (INL). Judging from the morphological features, the former two types of cells may belong to the displaced amacrine cells and the latter to the amacrine cells. LH-RH-positive fibers were found in the nerve fiber layer, GL, IPL, INL and outer plexiform layer.

Animals↗
PubMed1982

Regional distribution of somatostatin-containing neuron system in the lower brain stem of the neonatal rat.

With the indirect immunofluorescence technique, overall distribution of somatostatin (SRIF) neuron system in the lower brain stem of the neonatal rats were examined. The present study demonstrated numerous SRIF-positive structures in various lower brain stem areas which are hardly seen in the adult lower brain stem. A possible role of SRIF in the lower brain stem was briefly discussed.

Animals↗
PubMed1982

Phylogenetical development of somatostatin-containing cells in the retina from teleosts to mammals: immunohistochemical analysis.

The distribution of somatostatin (SRIF) in the retina of various vertebrates (from teleosts to mammals) was investigated by means of indirect immunohistochemical technique. The present study revealed that there exists marked differences in topography of SRIF-containing cell systems between higher vertebrates (birds and rats) and lower vertebrates (amphibian and teleosts). The retinas of the higher vertebrates contain abundant SRIF-positive structures, while those of the lower vertebrates contain a few. Phylogenetical development of retinal SRIF-system was briefly discussed in this study.

Animals↗
PubMed1982

Localization of substance P-like immunoreactivity in the anterior eye segment of squirrels: an immunohistochemical analysis.

Localization of substance P (SP)-like immunoreactivity in the anterior eye segment of the squirrel was examined immunohistochemically. The present study demonstrates a dense network of SP-positive fibers in the ciliary body, particularly in the muscle layers, and several SP-positive fibers in the iris, in addition to scattered SP-positive fibers in the cornea. These facts strongly suggest that SP has an important role in the physiologic functions of the anterior eye segment.

Animals↗
PubMed1982

Overall distribution of glucagon-like immunoreactivity in the chicken retina: an immunohistochemical study with flat-mounts.

Pancreatic glucagon-like immunoreactivity (GLI) in the chicken retina was investigated by immunohistochemical methods with frozen sections and flat-mounts. Observations of the frozen sections showed that GLI is localized in the amacrine cells. Flat-mounts showed the GLI cells are evenly localized in the retina (n= or approximately 400/mm2) and composed to two types of cells--one is larger and the other is small. The former cell type occupies mainly the peripheral retinal region and the latter the central region. In addition, flat-mounts showed two types of GLI fiber plexuses in the inner plexiform layer; one is located in the area between laminae 2 and 3 and runs circularly and the other is located in lamina 1 and runs randomly. The relationship between GLI and cyclic AMP was also examined. an increase of the formation of cyclic AMP was caused by pancreatic glucagon in the chicken retina, suggesting that this peptide might have neurotransmitter or neuromodulator roles in the chicken retina.

Animals↗
PubMed1981

Ontogeny of somatostatin-containing neuron system of the rat: immunohistochemical observations. I. Lower brainstem.

The ontogeny of the somatostatin (SRIF) neuron system in the lower brainstem of the rat was analyzed using the indirect immunofluorescence technique of Coons. SRIF-positive structures first appeared in the primordium of the ventral nucleus of the lemniscus lateralis of the rat fetus corresponding to gestational day 15 (12-14-mm embryos). On and after gestational day 15, these structures appeared in progressively more diverse areas of the lower brainstem and continued to show an increase in number and intensity up till birth. The maximum SRIF-positive structures were histochemically identified in the lower brainstem at the perinatal stage. However, after birth, the numbers of SRIF-positive structures in the lower brainstem began to decrease as the rat grew and none or only a few SRIF-positive structures were detected in the adult rats. This ontogenetical study of the SRIF neuron system on the lower brainstem of the rat strongly suggests that SRIF might play an important role in the development of the lower brainstem other than in its neurotransmitter or neuromodulator function.

Aging↗
PubMed1981

Morphological study of noradrenaline innervation in the caudal raphe nuclei with special reference to fine structure.

Previous histofluorescence studies have demonstrated that the caudal raphe nuclei (CRa) of the rat, particularly the ventral portion (VCRa), contains a very high density of noradrenaline (NA) terminals and in the present study we attempted to elucidate the origins and free structure of the NA terminals in this region. The majority of NA terminals found in the VCRa originated from A1 and A3 NA neurons and disclosed that a small number of very strongly fluorescent fibers located along the blood vessels arise from the superior cervical ganglion (SGC). Electron microscopic analysis after potassium permanganate fixation demonstrated that the NA terminals originated from A1 and A3 NA neurons are connected with neuronal elements, while NA fibers from the SGC were identified among the vascular elements. Axodendritic contacts were found to be predominant among the synapselike contacts of NA terminals in this area.

Animals↗
PubMed1981

Distribution of somatostatin in the frog brain, Rana catesbiana, in relation to location of catecholamine-containing neuron system.

The distribution of somatostatin (SRIF)-immunoreactive structures in the central nervous system of the bull frog (both with and without treatment of colchicine) was studied, using the indirect immunofluorescence technique of Coons and co-workers (Coons, '58). SRIF-containing cells were observed in more than ten areas including the spinal cord. These SRIF-positive cells showed segmental distribution, in that SRIF-positive neurons were identified in various areas at various brain levels. An extensive network of SRIF-positive fibers was found in most parts of the central nervous system. The distribution of a catecholamine (CA)-containing neuron system in the frog brain is also presented in this study. The possible interactions between SRIF and CA neurons systems are briefly discussed.

Animals↗
PubMed1981

Topographic atlas of somatostatin-containing neurons system in the avian brain in relation to catecholamine-containing neurons system. I. Telencephalon and diencephalon.

The morphological organization of the somatostatin (SRIF)-positive neurons in the forebrain (telencephalon and diencephalon) of the warbling grass parakeet (Melopsittacus undulatus) was studied using the indirect immunohistochemical technique of Coons and co-workers ('58). In the telencephalon, a number of SRIF-positive neurons was detected in the lobus paraolfactorius, hippocampus, and paleostriatum. Furthermore, scattered SRIF-labeled cells were noticed in the area corticoidea dorsolateralis and area temporoparieto-occipitalis. A moderate density of immunoreactive fibers was found in the above areas. In addition, although the septal areas was devoid of SRIF-positive neurons, this area contained a moderate occurred in the following hypothalamic areas: (1) nucleus medialis hypothalami posterior, (2) lateral hypothalamus, and (3) mammillary nucleus. The bird hypothalamus also received a strikingly massive SRIF innervation. The heaviest concentration of SRIF-labeled fibers was detected in the medial eminence. Many SRIF-labeled fibers were also observed in other hypothalamic regions. Their locations roughly corresponded in many cases to the areas in which SRIF-positive neurons were disclosed. The overall distribution of the catecholamine system (CA) of the avian forebrain is also represented by means of histofluorescent technique. A possible interaction between SRIF and CA neurons systems is briefly discussed.

Animals↗
PubMed1981

Topographic atlas of somatostatin-containing neuron system in the avian brain in relation to catecholamine-containing neuron system. II. Mesencephalon, rhombencephalon, and spinal cord.

With the indirect immunofluorescence technique of Coon's and collaborators, overall distribution of the somatostatin (SRIF)-positive neurons system in the avian lower brain stem was explored. Numerous cell somata containing SRIF were identified in the interpeduncular nucleus and substantia grisea centralis (GCT) at the level of the nucleus nervi trochlearis. Furthermore, a moderate number of SRIF-positive neurons were seen in the tectum opticum, nucleus tractus solitarii, and spinal cord. Scattered labeled cells were noticed in the rhombencephalon. A dense network of SRIF-positive fibers was distributed widely in the lower brain stem of birds. Their locations corresponded in many cases to the areas where SRIF-positive neurons were found. The present study also presents the distribution of the catecholamine (CA) neuron system in the avian lower brain stem. Possible interactions between SRIF and CA neurons systems are briefly discussed.

Animals↗
PubMed1981

Comparative anatomy of the distribution of catecholamines within the inferior olivary complex from teleosts to primates.

The distribution of catecholamine (CA) in the inferior olivary complex (IO) of various vertebrate (from fish to monkey) was investigated by means of the histofluorescence technique. In addition, using rats, a further attempt was made to elucidate the origins of CA in the IO. The IO of the lower vertebrates (from fish to birds) was in general poorly innervated by the CA neuron system. IO in the lower mammals, such as insectivora and bats, contained only a few CA nerve terminals, while that in the higher mammals such as rat, guinea pig, rabbit, cat, and monkey revealed quite a number. In these animals, species-species patterns of CA nerve terminals were found. In the rat, the highest concentration was observed in the dorsal lamella of the principal nucleus and in guinea pig ventral lamella. In the rabbit and cat, maximum CA nerve terminals were detected in the dorsal accessory nucleus, while in the monkey, they were detected in the medial accessory nucleus. The retrograde tracer technique of horseradish peroxidase (HRP) suggested that the main source of the abundant CA terminals in IO of the rat might be A1, A2, and A3 noradrenaline neurons, though not locus coeruleus and not dopaminergic ones.

Animals↗
PubMed1981

Experimental immunohistochemical studies on the amygdalofugal peptidergic (substance P and somatostatin) fibers in the stria terminalis of the rat.

The amygdalofugal substance P (SP) and somatostatin (SRIF) neuron systems in the stria terminalis (ST) were investigated by means of the indirect immunofluorescence technique of Coons. SP- and SRIF-positive cells were mainly located in the area (Amc) between the central (ac) and medial (am) amygdaloid nuclei. Some extended medially into the am and laterally into the ac. Destruction of the Amc resulted in a marked reduction of SP- and SRIF-positive fibers in the ST. Furthermore, a substantial decrease in SP-positive fibers was seen in the dorsal part of the bed nucleus of the ST (stb), there was a small decrease in the SP-positive fibers in the lateral hypothalamus (LH), a significant decrease in the SRIF-positive fibers in the lateroventral part of the anterior hypothalamic nucleus (lvAH), and a small decrease in the SRIF-positive fibers in the LH. These facts indicate that the origins of a number of SP- and SRIF-positive fibers are the Amc and that the amygdalofugal SP pathway in the ST innervates stb and LH and the amygdalofugal SRIF pathway in the ST projects to lvAH and LH.

Amygdala↗
PubMed1981

Regional distribution of substance P-like immunoreactivity in the frog brain and spinal cord: immunohistochemical analysis.

With the indirect immunofluorescence technique of Coons, the overall distribution of the substance P (SP)-positive neuron system in the frog brain and spinal cord was explored. SP-positive cells were observed in more than ten areas, such as olfactory bulb, amygdaloid complex, septal area, bed nucleus of hippocampal commissure, hypothalamic periventricular zone, dorsal and ventral thalamus, infundibulum, torus semicircularis, optic tectum, the area dorsal to the interpeduncular nucleus, central gray matter of the mesorhombencephalon, and raphe region, etc. A dense network of SP-positive fibers was also widely distributed in the frog brain and spinal cord. SP-positive fibers were roughly divided into two types. One consisted of very fine SP-positive fibers and gave the region a diffuse appearance. The area medial to n. Bellonci, interpeduncular nucleus, n. isthmi, and optic tectum contained this type of SP-positive fibers. The other one consisted of clearly distinguishable varicose fibers. A number of SP-positive fibers located in the amygdaloid complex, striatal complex, hypothalamus, central gray matter of the mesorhombencephalon, trigeminal spinal nucleus, and posterior horn of the spinal cord belonged to this category. The functional role of the SP-positive neuron system in the central nervous system is also briefly discussed.

Animals↗
PubMed1981

New somatostatin-containing sites in the diencephalon of the neonatal rat.

Using an immunohistochemical technique, the present study demonstrated several new somatostatin-containing sites in the diencephalon of neonatal rats which have not been reported in adult animals. These areas are the area just lateral to the commissura posterior, the area between the optic tract and capsula interna, pars retrolenticularis and n. peripeduncularis.

Animals↗
PubMed1981

Somatostatin-like immunoreactivity in the facial, glossopharyngeal and vagal lobes of the carp.

A large number of somatostatin (SRIF)-containing structures was demonstrated in the vagal and glossopharyngeal lobes of the carp by means of the indirect immunofluorescent method. The present study further showed that the facial lobe is devoid of these structures. These facts indicate that SRIF may have an important role in relaying viscerosensory information from the vagal and glossopharyngeal nerve but not from the facial nerve.

Animals↗