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R Shigemoto

Publications and source records attributed to R Shigemoto.

At least 73 records · Page 4Linked to original sources
PubMed1996

Immunohistochemical localization of a metabotropic glutamate receptor, mGluR7, in ganglion neurons of the rat; with special reference to the presence in glutamatergic ganglion neurons.

Immunoreactivity for the metabotropic glutamate receptor 7 (mGluR7) and that for phosphate-activated glutaminase (PAG) were examined in the trigeminal (TG), dorsal root (DRG), nodose (NG), superior cervical, celiac, and pelvic ganglia of the rat. Virtually all neuronal cell bodies showed mGluR7-like immunoreactivity (mGluR7-LI) in these ganglia. On the other hand, PAG-like immunoreactivity (PAG) was seen in almost all neuronal cell bodies in the TG, DRG and NG, but not in the other ganglia. Co-existence of mGluR7- and PAG-LI in the TG, DRG and NG was confirmed by a double-immunofluorescence immunohistochemical method. The results indicate that virtually all sensory ganglion neurons are glutamatergic and equipped with mGluR7.

Animals↗
PubMed1996

Localization of the neuromedin K receptor (NK3) in the central nervous system of the rat.

The distribution of the neuromedin K receptor (NK3; NKR) in the central nervous system was investigated in the adult rat by using in situ hybridization and immunohistochemical techniques. The rabbit anti-NKR antibody was raised against a bacterial fusion protein containing a C-terminal portion of NKR and affinity purified with a Sepharose 4B column conjugated to the fusion protein. Immunoblot analysis was performed to test the reactivity and specificity of the antibody. Crude membrane was prepared from cDNA-transfected Chinese hamster ovary (CHO) cells expressing each of the rat NKR, substance P receptor (NK1; SPR), and substance K receptor (NK2; SKR) and from the hypothalamus, cerebral cortex, and cerebellum. Immunoreactive bands were observed specifically in the NKR-CHO cells, hypothalamus, and cerebral cortex but not in the SPR- or SKR-CHO cells, nor in the cerebellum. Molecular weights of the immunoreactive bands ranged from 73 to 89 kDa and from 59 to 83 kDa in the NKR-CHO cells and tissues, respectively. The distribution of NKR-like immunoreactivity coincided with that of NKR mRNA. The expression of NKR was indicated on neuronal cell bodies and dendrites. NKR was found to be expressed intensely or moderately in neurons in the glomerular and granule cell layers of the main olfactory bulb; glomerular and mitral cell layers of the accessory olfactory bulb; layers IV and V of the cerebral neocortex; medial septal nucleus; nucleus of the diagonal band; bed nucleus of the stria terminalis; globus pallidus; ventral pallidum; paraventricular nucleus; supraoptic nucleus; zona incerta; dorsal, lateral, and posterior hypothalamic areas; amygdaloid nuclei; medial habenular nucleus; ventral tegmental area; midbrain periaqueductal gray; interpeduncular nuclei; substantia nigra pars compacta; linear, median, dorsal, and pontine raphe nuclei; posteromedial tegmental nucleus; sphenoid nucleus; nucleus of the solitary tract; intermediate and rostroventrolateral reticular nuclei; and lamina II of the caudal spinal trigeminal nucleus and spinal dorsal horn. These findings are discussed in relation to the physiological functions associated with neuromedin K.

Animals↗
PubMed1996

Pre- and postsynaptic localization of a metabotropic glutamate receptor, mGluR2, in the rat brain: an immunohistochemical study with a monoclonal antibody.

A monoclonal antibody against a metabotropic glutamate receptor, mGluR2, was produced by using a glutathione S-transferase (GST) fusion protein containing an N-terminal sequence of rat mGluR2. Intense mGluR2-like immunoreactivity (mGluR2-LI) was seen mainly in neuropil of the cerebral cortical regions, hippocampus, olfactory bulb, some diencephalic nuclei, dorsal cochlear nucleus and cerebellar cortex. In the cerebellar cortex, mGluR2-LI was seen only in Golgi cells. In Ammon's horn, mGluR2-LI was marked in the stratum lucidum of CA3 and the stratum lacunosum-moleculare of CA1-CA3, but not detected in the stratum pyramidale. The results indicate that mGluR2 is located not only presynaptically but also postsynaptically.

Animals↗
PubMed1996

Metabotropic glutamate receptors mGluR2 and mGluR5 are expressed in two non-overlapping populations of Golgi cells in the rat cerebellum.

The metabotropic glutamate receptor subtypes mGluR2 and mGluR5, which are thought to be coupled respectively to the inhibitory cyclic adenosine monophosphate (cAMP) cascade and the phosphatidylinositol hydrolysis/Ca2+ cascade, are known to be expressed on Golgi cells in the granular layer of the rat cerebellar cortex. In the present immunohistochemical study with a monoclonal antibody against mGluR2 and a polyclonal antibody for mGluR5, we examined whether or not mGluR2- and mGluR5-like immunoreactivities were both present in single Golgi cells in the rat cerebellar cortex. In double immunofluorescence histochemistry, no Golgi cells showed mGluR2- and mGluR5-like immunoreactivities simultaneously. Of the total number of Golgi cells immunoreactive for mGluR2 or mGluR5, about 90% were mGluR2-like immunoreactive, and about 10% were mGluR5-like immunoreactive. Golgi cells with mGluR2-like immunoreactivity were distributed evenly in the granular layer of all the cerebellar regions, while those with mGluR5-like immunoreactivity were distributed more frequently in the I, II, VII-X lobules of the vermis and the copula pyramidis of the hemisphere than in other cerebellar regions. The results indicate that Golgi cells containing mGluR2 are segregated from those possessing mGluR5. These two populations of Golgi cells, each equipped with a different metabolic glutamate receptor coupled to a different intracellular signal transduction system, may play different roles in the glutamatergic neuronal circuits in the cerebellar cortex.

Animals↗
PubMed1996

Perisynaptic location of metabotropic glutamate receptors mGluR1 and mGluR5 on dendrites and dendritic spines in the rat hippocampus.

Ionotropic and metabotropic (mGluR1a) glutamate receptors were reported to be segregated from each other within the postsynaptic membrane at individual synapses. In order to establish whether this pattern of distribution applies to the hippocampal principal cells and to other postsynaptic metabotropic glutamate receptors, the mGluR1a/b/c and mGluR4 subtypes were localized by immunocytochemistry. Principal cells in all hippocampal fields were reactive for mGluR5, the strata oriens and radiatum of the CA1 area being most strongly immunolabelled. Labelling for mGluR1b/c was strongest on some pyramids in the CA3 area, weaker on granule cells and absent on CA1 pyramids. Subpopulations of non-principal cells showed strong mGluR1 or mGluR5 immunoreactivity. Electron microscopic pre-embedding immunoperoxidase and both pre- and postembedding immunogold methods consistently revealed the extrasynaptic location of both mGluRs in the somatic and dendritic membrane of pyramidal and granule cells. The density of immunolabelling was highest on dendritic spines. At synapses, immunoparticles for both mGluR1 and mGluR5 were found always outside the postsynaptic membrane specializations. Receptors were particularly concentrated in a perisynaptic annulus around type 1 synaptic junctions, including the invaginations at 'perforated' synapses. Measurements of immunolabelling on dendritic spines showed decreasing levels of receptor as a function of distance from the edge of the synaptic specialization. We propose that glutamergic synapses with an irregular edge develop in order to increase the circumference of synaptic junctions leading to an increase in the metabotropic to ionotropic glutamate receptor ratio at glutamate release sites. The perisynaptic position of postsynaptic metabotropic glutamate receptors appears to be a general feature of glutamatergic synaptic organization and may apply to other G-protein-coupled receptors.

Animals↗
PubMed1995

Presynaptic localization of a metabotropic glutamate receptor, mGluR7, in the primary afferent neurons: an immunohistochemical study in the rat.

An antibody which recognizes specifically a metabotropic glutamate receptor, mGluR7, was produced by using a trpE fusion protein containing a C-terminal sequence of rat mGluR7. Neuropil in laminae I and II of the dorsal horn of the rat, as well as many neuronal cell bodies in the dorsal root ganglion, showed mGluR7-like immunoreactivity; the immunoreactivity in neuropil was seen in axon terminals, which were filled with round synaptic vesicles and constituted axodendritic and axosomatic asymmetric synapses. The mGluR7-like immunoreactivity in laminae I and II in the dorsal horn was reduced after dorsal rhizotomy. The results indicate that some axon terminals of the primary afferent fibers to laminae I and II of the dorsal horn are provided with mGluR7.

Animals↗
PubMed1995

Distributions of the mRNAs for L-2-amino-4-phosphonobutyrate-sensitive metabotropic glutamate receptors, mGluR4 and mGluR7, in the rat brain.

The distribution of mRNAs for metabotropic glutamate receptors, mGluR4 and mGluR7, which are highly sensitive for L-2-amino-4-phosphonobutyrate (L-AP4), was examined in the central nervous system of the rat by in situ hybridization. In general, the hybridization signals of mGluR7 mRNA were more widely distributed than those of mGluR4 mRNA, and differential expression of mGluR4 mRNA and mGluR7 mRNA was clearly indicated in some brain regions. Intense or moderate expression of mGluR4 mRNA was detected in the granule cells of the olfactory bulb and cerebellum, whereas no significant expression of mGluR7 mRNA was found in these cells. In other neurons or regions where mGluR7 mRNA was intensely or moderately expressed, no significant expression of mGluR4 mRNA was observed. Such were the mitral and tufted cells of the olfactory bulb; anterior olfactory nucleus; neocortical regions; cingulate cortex; retrosplenial cortex; piriform cortex; perirhinal cortex; CA1; CA3; granule cells of the dentate gyrus; superficial layers of the subicular cortex; deep layers of the entorhinal, parasubicular, and presubicular cortices; ventral part of the lateral septal nucleus; septohippocampal nucleus; triangular septal nucleus; nuclei of the diagonal band; bed nucleus of the stria terminalis; ventral pallidum; claustrum; amygdaloid nuclei other than the intercalated nuclei; preoptic region; hypothalamic nuclei other than the medial mammillary nucleus; ventral lateral geniculate nucleus; locus coeruleus; Purkinje cells; many nuclei of the lower brainstem other than the superior colliculus, periaqueductal gray, interpeduncular nucleus, pontine nuclei, and dorsal cochlear nucleus; and dorsal horn of the spinal cord. Both mGluR4 mRNA and mGluR7 mRNA were moderately or intensely expressed in the olfactory tubercle, superficial layers of the entorhinal cortex, CA4, septofimbrial nucleus, intercalated nuclei of the amygdala, medial mammillary nucleus, many thalamic nuclei, and pontine nuclei. Intense expression of both mGluR4 mRNA and mGluR7 mRNA was further detected in the trigeminal ganglion and dorsal root ganglia, whereas no significant expression of them was found in the pterygopalatine ganglion and superior cervical ganglion. The results indicate differential roles of the L-AP4-sensitive metabotropic glutamate receptors in the glutamatergic nervous system.

Animals↗
PubMed1995

Expression of c-fos protein in substance P receptor-like immunoreactive neurons in response to noxious stimuli on the urinary bladder: an observation in the lumbosacral cord segments of the rat.

Chemical irritation of the urinary bladder with formalin in the rat induced c-fos protein-like immunoreactivity in more than 80% of substance P receptor-like immunoreactive (SPR-LI) neurons of the dorsal commissural nucleus, sacral parasympathetic nucleus and lamina I in the 6th lumbar and 1st sacral cord segments. These neurons with SPR-LI may receive noxious information from the urinary bladder through the primary afferent fibers with substance P.

Animals↗
PubMed1995

Synaptic organization and ultrastructural features of the substance P-receptor-like immunoreactive neurons in the nucleus intermediolateralis of rats.

Synaptic and ultrastructural organization in the intermediolateral nucleus (IML) of rat were investigated with electron microscopy combined with pre-embedding immunohistochemistry for substance P (SP)-receptor (SPr). SPr immunoreactivity in IML was found in the vicinity of the cellular membrane of the perikarya and dendritic profiles of the small sized neurons, ranging from 15 to 25 microns in length. A SPr-immunoreactive (SPr-ir) soma had symmetric or asymmetric synaptic contacts with three to five unlabeled axon terminals. Two different types of axon terminals made synapses on the SPr soma, one contained 20-30 nm pleomorphic vesicles and large dense cored vesicles and the other contained clear pleomorphic vesicles of 30-50 nm in size. Occasionally, SPr-ir dendrites are very closely apposed to the blood capillary. Our present results suggested the possibility that the IML SPr-ir neurons might be activated by several kinds of synaptic inputs and SP provided from blood flow.

Animals↗
PubMed1995

Spinoparabrachial tract neurons showing substance P receptor-like immunoreactivity in the lumbar spinal cord of the rat.

By using substance P receptor (SPR) immunofluorescence histochemistry combined with fluorescent retrograde labeling, SPR-like immunoreactive (SPR-LI) neurons sending their axons to the lateral parabrachial region were observed in the lumbar spinal cord of the rat. After injection of Fluoro-Gold into the lateral parabrachial region, retrogradely labeled neurons with SPR-LI were seen frequently in lamina I and the lateral spinal nucleus, and occasionally in laminae IV and V, with a predominantly contralateral distribution. Some of these neurons, especially those in lamina I, may convey nociceptive information to the lateral parabrachial region.

Animals↗
PubMed1995

Specific deficit of the ON response in visual transmission by targeted disruption of the mGluR6 gene.

Taking advantage of the restricted expression of metabotropic glutamate receptor subtype 6 (mGluR6) in retinal ON bipolar cells, we generated knockout mice lacking mGluR6 expression. The homozygous mutant mice showed a loss of ON responses but unchanged OFF responses to light. The mutant mice displayed no obvious changes in retinal cell organization nor in the projection of optic fibers to the brain. Furthermore, the mGluR6-deficient mice showed visual behavioral responses to light stimulation as examined by shuttle box avoidance behavior experiments using light exposure as a conditioned stimulus. The results demonstrate that mGluR6 is essential in synaptic transmission to the ON bipolar cell and that the OFF response provides an important means for transmitting visual information.

Animals↗
PubMed1995

Trigeminoparabrachial projection neurons showing substance P receptor-like immunoreactivity in the rat.

By means of substance P receptor (SPR) immunofluorescence histochemistry combined with Fluoro-Gold fluorescent retrograde labeling, SPR-like immunoreactive neurons in the caudal subnucleus of the spinal trigeminal nucleus of the rat were observed to send their axons to the nucleus of Kölliker-Fuse and ventrolateral part of the lateral parabrachial nucleus bilaterally with a clear ipsilateral dominance. These neurons were distributed mainly in lamina I, and additionally in lamina III.

Animals↗
PubMed1995

Localization of substance P receptors in central neural structures controlling daily rhythms in nocturnal rodents.

Brain areas involved in the genesis and control of daily rhythms receive a prominent neural input that contains the neurotransmitter substance P (SP), a peptide putatively involved in the synchronization of circadian rhythms by environmental light. We investigated the localization of receptors to SP in the suprachiasmatic nucleus of the hypothalamus (SCN) and in the intergeniculate leaflet of the thalamus (IGL) of the rat and hamster using in situ hybridization histochemistry and immunohistochemistry. Consistently with that previously described in the rat, a neuronal population distributed along the lateral margin and at the dorso-latero-caudal aspect of the hamster SCN expresses moderately the mRNA encoding the SP receptor. In both rat and hamster, immunohistochemical data confirm the previous finding and reveal an almost complete absence of SP receptors in the ventral part of the SCN, which receives a direct projection from the retina. In the IGL of both species, numerous neurons prominently express the mRNA encoding the SP receptor. The immunostaining shows a high density of SP receptors on perikarya and dendrites throughout the nucleus. A dense staining is also observed on individual cells and processes bordering the lumen of blood vessels in the SCN and IGL.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Immunohistochemical localization of substance P receptor in the central nervous system of the adult rat.

In an attempt to reveal the function sites of substance P (SP) in the central nervous system (CNS), the distribution of SP receptor (SPR) was immunocytochemically investigated in adult rat and compared with that of SP-positive fibers. SPR-like immunoreactivity (LI) was mostly localized to neuronal cell bodies and dendrites. Neurons with intense SPR-LI were distributed densely in the cortical amygdaloid nucleus, hilus of the dentate gyrus, locus ceruleus, rostral half of the ambiguus nucleus, and intermediolateral nucleus of the thoracic cord; moderately in the caudatoputamen, nucleus accumbens, olfactory tubercle, median, pontine, and magnus raphe nuclei, laminae I and III of the caudal subnucleus of the spinal trigeminal nucleus, and lamina I of the spinal cord; and sparsely in the cerebral cortex, basal nucleus of Meynert, claustrum, gigantocellular reticular nucleus, and lobules IX and X of the cerebellar vermis. Neurons with weak to moderate SPR-LI were distributed more widely throughout the CNS. The regional patterns of distribution of SPR-LI were not necessarily the same as those of SP-positive fibers. The entopedunucular nucleus, substantia nigra, and lateral part of the interpeduncular nucleus showed intense SP-LI but displayed almost no SPR-LI. Conversely, the hilus of the dentate gyrus, anterodorsal thalamic nucleus, central nucleus of the inferior colliculus, and dorsal tegmental nucleus showed intense to moderate SPR-LI but contained few axons with SP-LI. These findings confirmed the presence of the "mismatch" problem between SP and SPR localizations. However, the distribution of SPR-LI was quite consistent with that of the SP-binding activity, which has been studied via autoradiography. This indicates that the sites of SPR-LI revealed in the present study represent most, if not all, sites of SP-binding activity.

Animals↗
PubMed1994

Differential expression of five N-methyl-D-aspartate receptor subunit mRNAs in the cerebellum of developing and adult rats.

Five N-methyl-D-aspartate (NMDA) receptor subunits have been identified thus far: NR1, NR2A, NR2B, NR2C, and NR2D. Here, we have analyzed the expression patterns of mRNAs for the NMDA receptor subunits in the developing and adult rats by in situ hybridization. The developmental changes of the expression patterns were most salient in the cerebellum. In the external granular layer, hybridization signals of mRNAs for NR1, NR2A, NR2B, and NR2C appeared by postnatal day 3, but no NR2D mRNA was expressed at any developmental stage examined. The NR1 mRNA was expressed in all cerebellar neurons at all developmental stage examined. The NR1 mRNA was expressed in all cerebellar neurons at all developmental stages examined. The signals for the NR2A mRNA appeared in Purkinje cells and granule cells during the second postnatal week. The signals for the NR2B mRNA in granule cells were seen transiently during the first 2 weeks after birth. The signals for NR2C mRNA appeared in granule cells and glial cells during the second postnatal week. The signals for NR2D mRNA appeared transiently in Purkinje cells during the first 8 postnatal days; in adult rats, these were seen in stellate and Golgi cells. In the cerebellar nuclei, mRNAs for NR1, NR2A, NR2B, and NR2D were more or less expressed on postnatal day 0, while expression signals for the NR2C mRNA were first detected in postnatal day 14. Thus, the most conspicuous changes of expression patterns were observed in the cerebellar cortex during the first 2 weeks after birth, when development and maturation of the cerebellum proceed most rapidly.

Animals↗
PubMed1994

Developmentally regulated postsynaptic localization of a metabotropic glutamate receptor in rat rod bipolar cells.

The retinal bipolar cell receiving glutamate transmission from photoreceptors mediates a key process in segregating visual signals into ON center and OFF center pathways. This transmission involves a G protein-coupled metabotropic glutamate receptor (mGluR). Immunocytochemical and immunoelectron microscopic studies indicate that restricted localization of a specific mGluR subtype, mGluR6, at the postsynaptic site of the rat rod bipolar cell. This specialization is developmentally regulated: mGluR6 is initially distributed in both the soma and dendrites and is finally concentrated on the postsynaptic site. The mGluR6 localization is reversed when photoreceptors degenerate in the mutant rat with retinal dystrophy. Evidence is thus presented indicating specialized, developmentally regulated receptor distribution in the central nervous system and the crucial role of mGluR6 in photoreceptor-bipolar cell synaptic transmission.

Amino Acid Sequence↗
PubMed1994

Expression of mRNAs of L-AP4-sensitive metabotropic glutamate receptors (mGluR4, mGluR6, mGluR7) in the rat retina.

Expression patterns of mRNAs of L-AP4-sensitive metabotropic glutamate receptors (mGluR4, mGluR6, mGluR7) in the rat retina were examined by northern blot analysis and in situ hybridization histochemistry. Expression patterns of mGluR4 and mGluR7 mRNAs were quite different from that of mGluR6 mRNA which was expressed at the outer part of the inner nuclear layer. The mGluR4 mRNA was expressed on the cell bodies of the ganglion cells, but not in the inner or outer nuclear layer. The expression of mGluR7 mRNA was observed throughout the entire region of the inner nuclear layer and on the cell bodies of the ganglion cells.

Aminobutyrates↗