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R Arai

Publications and source records attributed to R Arai.

At least 19 recordsLinked to original sources
PubMed1992

Immunohistochemical localization of calretinin in the rat lateral geniculate nucleus and its retino-geniculate projection.

In the present study, we examined the distribution of calretinin-immunoreactive neuronal cell bodies and fibers in the lateral geniculate nucleus of the rat. In normal rats, clusters of immunoreactive cell bodies were found in: (i) the rostral portion of the ventral lateral geniculate nucleus pars medialis (VLGM), (ii) the intergeniculate leaflet (IGL), (iii) the intermediate region between the VLGM and the ventral lateral geniculate nucleus pars lateralis (VLGL), (iv) the caudomedial portion of the VLGM, and (v) the caudolateral portion of the VLGM. In the dorsal lateral geniculate nucleus (DLG), immunoreactive cell bodies were rarely observed. After uni- or bilateral eye enucleation, no significant alteration in the morphological features or distribution of immunoreactive cell bodies was detected in the lateral geniculate nucleus. In normal rats, immunoreactive fibers formed dense plexuses in: (i) the DLG, (ii) the external layer of the VLGL, (iii) the internal layer of the VLGL, (iv) the IGL, (v) the caudomedial portion of the VLGM, and (vi) the optic tract. After unilateral eye enucleation, immunoreactive fibers in the external layer of the VLG and in the optic tract almost totally disappeared on the contralateral side to the lesion. Unilateral eye enucleation caused a significant decrease of immunoreactive fibers in the DLG and in the internal layer of the VLGL, but a substantial number of immunoreactive fibers still remained there. In the IGL and the caudomedial portion of the VLGM, no observable alteration in the distribution of immunoreactive fibers was detected after uni- or bilateral eye enucleation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Calretinin distribution in the thalamus of the rat: immunohistochemical and in situ hybridization histochemical analyses.

The distribution of calretinin-containing cells was examined by in situ hybridization histochemistry and compared with the immunohistochemical mapping of calretinin in the thalamus of the rat. Results revealed a close correspondence between the immunohistochemical localization of cell bodies and the messenger RNA label produced by the calretinin oligonucleotide probe. Calretinin cells were most prominent in the midline (paraventricular, reuniens, rhomboid) and intralaminar (central medial, paracentral) nuclei and in a group of cells along the rostral central gray which appeared continuous with the caudal extent of the midline nuclei. A subpopulation of calretinin cell bodies was also identified in the reticular nucleus. The mediorostral lateral posterior nucleus, subparafascicular, lateral geniculate and habenular nuclei also contained calretinin messenger RNA probe label. In contrast, no positive cells were found in the anterior, ventral or posterior thalamic nuclei. The distribution of calretinin cells did not correspond directly with that of other histochemical markers. Thus, the in situ hybridization histochemical and immunohistochemical results revealed calretinin as a unique identifying marker for distinct sets of thalamic neurons.

Animals↗
PubMed1992

Intensification of labelings of the immunogold silver staining method by gold toning.

We evaluated the applicability of the gold toning procedure to the immunogold silver staining method using monoclonal antibody against dopamine. Immunolabeling was examined in the rat substantia nigra at light and electron microscopic levels. Vibratome sections of fixed midbrains were incubated with anti-dopamine antiserum and then with 5 nm colloidal gold bound to goat anti-mouse immunoglobulin. Silver staining of these sections produced a light brown immunolabeling. After the sections were processed by gold toning, the labeling became intense black. At a light microscopic level, these high contrast signals were retained after the sections were osmicated and embedded in Epon. At an electron microscopic level, signal-to-noise ratio was high, and the positive staining could easily be verified at a low-power magnification. The technique described here, the gold-toned immunogold silver staining method, provides high contrast signals and is much more sensitive than immunogold silver staining alone. This method, therefore, has great potential for use in immunohistochemical analysis of the central nervous system.

Animals↗
PubMed1992

Combined use of silver staining of the retrograde tracer WGAapoHRP-Au and pre-embedding immunocytochemistry for electron microscopy: demonstration of dopaminergic terminals in synaptic contact with striatal neurons projecting to the substantia nigra in the rat.

We investigated the applicability of the pre-embedding immunoperoxidase technique to WGAapoHRP-Au retrograde tracing. After injection of the tracer into the substantia nigra of rat, the brain was fixed and cryostat sections were immunostained for dopamine. The sections were osmicated and silver-stained to amplify the colloidal gold particles. Products of both the immunoperoxidase staining and the silver staining could be detected and distinguished by electron microscopy at low magnification. The ultrastructure was so well preserved that synaptic characteristics could be investigated. Dopaminergic terminals were demonstrated to synapse with striatal neurons projecting to the substantia nigra.

Animals↗
PubMed1991

Ultrastructural localization of galanin immunoreactivity in the rat median eminence.

The aim of this study was to examine, by use of a pre-embedding immunoperoxidase technique, the ultrastructural localization of galanin immunoreactivity in the external layer of the rat median eminence. Galanin immunoreactivity was only observed in axonal profiles. Immunoreactive fibers were found in contact with the following non-immunoreactive structures: (1) axonal profiles that contain dense granular vesicles and clear vesicles, (2) axonal profiles that contain predominantly clear vesicles, (3) glial cell bodies, and (4) processes of tanycytes. Labeled terminals were also observed in the proximity of the perivascular space of the portal vessels. The results suggest possible interactions between galanin-immunoreactive terminals and other terminals containing peptide and/or other transmitters in the external layer of the median eminence.

Animals↗
PubMed1991

Immunohistochemical localization of calretinin in the rat hindbrain.

The localization of calretinin in the rat hindbrain was examined immunohistochemically with antiserum against calretinin purified from the guinea pig brain. Calretinin immunoreactivity was found within neuronal elements. The distribution of calretinin-immunoreactive cell bodies and fibers is presented in schematic drawings and summarized in a table. Major calretinin-immunoreactive neurons were found in the lateral and medial geniculate nuclei, substantia nigra, ventral tegmental area, interpeduncular nucleus, periaqueductal gray, mesencephalic trigeminal nucleus, superior and inferior colliculi, pontine nuclei, parabrachial nucleus, dorsal and laterodorsal tegmental nuclei, cochlear nuclei, vestibular nuclei, medullary reticular nuclei, nucleus of the solitary tract, area postrema, substantia gelatinosa of the spinal trigeminal nucleus, and cerebellum. These results show that distinct calretinin-immunoreactive neurons are widely distributed in the rat hindbrain.

Animals↗
PubMed1991

Evidence for a colocalization of oxytocin mRNA and galanin in magnocellular hypothalamic neurons: a study combining in situ hybridization and immunohistochemistry.

The possible colocalization of oxytocin (OT) and galanin (GAL) was studied by combining, on the same cryostat sections, in situ hybridization (ISH) for OT mRNA with a tritiated oligonucleotide probe and immunohistochemistry (ICC) of GAL. Many cells were either labelled by ISH (OT mRNA containing cells), or by ICC (GAL containing cells). Moreover, some magnocellular neurons in the supraoptic and paraventricular nuclei were labelled for both OT mRNA and GAL. These results demonstrate that some magnocellular neurons of the rat hypothalamus contain both GAL and OT. This approach is suitable for studying the intracellular distribution of OT gene expression and mature GAL under different physiological or experimental conditions.

Animals↗
PubMed1991

Monoaminergic interaction in the central nervous system: a morphological analysis in the locus coeruleus of the rat.

The locus coeruleus of the rat is richly innervated by many aminergic neurons varying in amine content and in site of origin. There are adrenergic and noradrenergic neurons originating in the medulla oblongata, dopaminergic from the hypothalamus, serotonergic from the mesencephalon and also intrinsic noradrenergic neurons in the locus coeruleus complex. Of these, adrenergic and dopaminergic inputs appear relatively specific and powerful.

Animals↗
PubMed1990

Hypothalamic galanin-immunoreactive neurons projecting to the posterior lobe of the rat pituitary: a combined retrograde tracing and immunohistochemical study.

UNLABELLED: To identify the galanin-immunoreactive neurons projecting to the posterior lobe of the pituitary in the rat hypothalamus, a retrograde tracer (complex of wheat germ agglutinin-enzymatically inactive horseradish peroxidase-colloidal gold) was injected into the posterior lobe of the pituitary. Sections of the hypothalamus were treated with a combination of silver enhancement of retrogradely transported tracer and immunohistochemistry of galanin. Of the total number of hypothalamic cells doubly labeled with retrograde tracing and galanin-immunostaining, 56-60% were found in the supraoptic nucleus, 18-23% in the retrochiasmatic nucleus, 8-10% in the lateral magnocellular portion of the paraventricular nucleus. The ratio of (number of doubly labeled cells/number of galanin-immunoreactive cells) in each of the above regions was similar to the ratio of (number of retrogradely labeled cells/number of Nissl-stained cells) in the supraoptic nucleus. Of all retrogradely labeled cells in the hypothalamus, 51-56% also contained galaninlike immunoreactivity. IN CONCLUSION: (1) galanin-immunoreactive fibers in the posterior lobe of the pituitary originate mainly in the supraoptic nucleus, retrochiasmatic nucleus, and lateral magnocellular portion of the paraventricular nucleus, (2) most of galanin-immunoreactive cells in these regions project to the posterior lobe of the pituitary, and (3) about half the neurons constituting the hypothalamo-neurohypophyseal system contain galaninlike immunoreactivity.

Animals↗
PubMed1990

Nerve supply to the posterior longitudinal ligament and the intervertebral disc of the rat vertebral column as studied by acetylcholinesterase histochemistry. I. Distribution in the lumbar region.

The nerve supply to the posterior longitudinal ligament (PLL) and the intervertebral disc (IVD) of the lumbar vertebra was investigated by acetylcholinesterase (AchE) enzyme histochemistry in the rat. The meningeal branch of the spinal nerve (the sinuvertebral nerve) enters the vertebral canal and divides into ascending and descending branches which fuse with those from adjacent vertebrae. They give off transverse branches, connecting with those from the opposite side to form the superficial nerve fibre network in the intervertebral segment, which spreads to the vertebral segment of the PLL. Apart from this superficial nervous network, many nerve fibres enter through the posterolateral portion of the annulus fibrosus (AF) and form a dense, fine nerve fibre network in the deep layer of the intervertebral portion of the PLL and the superficial layer of the AF. Nerve fibres and terminals cannot be found in the deep layer of the AF or the nucleus pulposus. In the central part of the deeper nerve network there are few nerve terminals whereas there are abundant free nerve endings in the peripheral zones. It is suggested that these abundant nerve fibres may be correlated with various functions characteristic of this region and that they may be important in the regulation of movement and posture in the vertebral column.

Acetylcholinesterase↗
PubMed1990

Nerve supply to the posterior longitudinal ligament and the intervertebral disc of the rat vertebral column as studied by acetylcholinesterase histochemistry. II. Regional differences in the distribution of the nerve fibres and their origins.

Regional differences of the distribution and the origin of the nerve fibres of the posterior longitudinal ligament (PLL) and the intervertebral disc (IVD) were investigated by acetylcholinesterase (AchE) enzyme histochemistry in the rat. The deeper nerve network was well-developed at the lower thoracic and the upper lumbar vertebral levels, but it was hardly seen at the mid-thoracic level. This difference can be correlated with the extensibility of the PLL. The experimental study revealed that the AchE-positive nerve fibres in the PLL and the IVD were mostly derived from the spinal ganglia, that the superficial nerve network was supplied by the spinal ganglia bilaterally and polysegmentally, and that the deeper nerve network was supplied bilaterally but unisegmentally.

Acetylcholinesterase↗
PubMed1989

Origin of the met-enkephalinergic innervation of the lateral septum in the rat.

The location of the cells giving rise to the methionine-enkephalin (Met-Enk)-ergic innervation of the lateral septal nucleus has been investigated in the rat by combining immunohistochemistry and retrograde axonal tracing. Small volumes (0.06 microliter) of apo-horseradish peroxidase (Apo-HRP) conjugated to wheat-germ agglutinin (WGA) and coupled with colloidal gold particles (WGA-ApoHRP-gold) were injected into the lateral septum. The retrogradely labeled cell bodies were visualized by silver intensification of the gold particles on Vibratome sections that were subsequently processed for immunohistochemistry for Met-Enk. Cells labeled with WGA-ApoHRP-gold were observed in the septal area, throughout the hypothalamus (mainly in the perifornical and lateral nuclei) and in the mesencephalon. The localization of Met-Enk-immunoreactive cells was as previously described. With the exception of a few septal cells close to the injection site, doubly labeled cells were found only in the perifornical nucleus of the hypothalamus. Almost all perifornical magnocellular cells were doubly labeled ipsilateral to the injection site, whereas on the opposite side, only about 25% of the Met-Enk-immunoreactive cells contained WGA-ApoHRP-gold. Other brain regions containing retrogradely labeled or Met-Enk-immunoreactive cells (particularly the raphe nuclei) did not show double-labeled neurons. This study demonstrates, using a new and sensitive technique for specific neurochemical tracing of tracts, that the origin of the Met-Enk-ergic innervation of the rat lateral septal nuclei lies in the magnocellular perifornical nuclei of the hypothalamus. The precise involvement of this pathway in limbic functions remains to be determined.

Animals↗
PubMed1988

[Cyclophosphamide, adriamycin and vincristine (CAV) in the treatment of small cell lung cancer].

Thirty-nine previously untreated small cell lung cancer patients received cyclophosphamide (CTX) + adriamycin (ADM) + vincristine (VCR) (CAV). The doses initially used were CTX 1,000 mg/body day 1, ADM 50 mg/body day, VCR 1 mg/body day, 8, 15 or 2 mg/body day(group A). Later, CTX 1,000 mg/m2 day, ADM 60 mg/m2 day, VCR 1.4 mg/m2 day were used. All patients had PS 0-3, 24 had limited disease (LD) and 15, extensive disease (ED). The overall response rate and the complete response (CR) rates were 63% (15/24) and 21% (5/24) for LD, and 21% (3/14) and 0% (0/14) for ED, respectively. The median response durations were 22 weeks for LD and 33 weeks for ED. The median CR duration in LD patients was 23 weeks. Twelve LD and 1 ED patient received thoracic radiotherapy (RT) optionally after 2-4 courses of CAV therapy. Eventually, 8 patients achieved CR. The median survival for LD, ED and all cases were 43 weeks, 37 weeks and 41 weeks, respectively. The 1, 2 and 3-year survival rates were 42, 25 and 21% for LD, and 40, 7 and 0% for ED. Three patients were long-term disease-free survivors (greater than 3 years), and these had LD and received RT. There were 3 chemotherapy-related deaths (2 patients with leukopenia + infection, 1 patient with drug-induced pneumonitis). The survival results of CAV therapy in our hospital were comparable with the recent results of chemotherapies available against small cell lung cancer.

Aged↗
PubMed1988

[Phase II studies of a single agent and a cis-platinum-based two-drug combination in patients with non-small cell lung cancer].

Phase II studies of single agent and CDDP-based two drug combination were performed in 189 patients with inoperable non-small cell lung cancer. Six drug regimens were performed: CDDP alone, VDS alone, Epi-ADM alone, CDDP + VDS, CDDP + CPA, CDDP + ADM. The response rates were 15.4% (6/39) with CDDP alone, 8.0% (2/25) with VDS alone, 6.1% (2/33) with Epi-ADM alone, 26.7% (8/30) with CDDP + VDS, 14.3% (4/28) with CDDP + CPA, 17.6% (6/34) with CDDP + ADM and one CR was performed with CDDP + ADM. In patients with no prior chemotherapy, the response rates were 20.0% (6/30), 11.8% (2/17), 12.5% (2/16), 26.7% (8/30), 16.0% (4/25) and 25.0% (3/12), respectively. The median survival times were 25, 27, 23, 33, 25, and 45 weeks, respectively. The efficacy of CDDP in non-small cell lung cancer patients was re-confirmed, and that of CDDP + VDS, CDDP + ADM was suggested. No death due to toxicity occurred and toxicity was generally tolerable.

Aged↗
PubMed1988

[Combined radiotherapy and chemotherapy modalities in the treatment of lung cancer].

The aim of combined modality treatment of lung cancer is to improve control of both local and metastatic disease. Retrospective reviews of the combined RT and CT modality in limited-stage small cell lung cancer (SCLC) showed an improvement of median survival and long term survival compared with CT alone. Among reports of 7 prospective trials in which patients were randomized so as to receive CT alone or CT with chest irradiation, combined modality treatment significantly increased the CR rate in 3/3, and the overall survival was significantly prolonged in 3/7. Concurrently combined modality treatment has a modest survival benefit in limited stage SCLC. Our phase 2 study combining RT with cisplatin-containing CT showed better improvement of response and survival than CT alone in non-small cell lung cancer (NSCLC). Four reports of prospective randomized studies have been performed to determine whether combined RT and combination chemotherapy might be better than RT alone in limited-stage NSCLC. Two of these studies demonstrated a survival and response advantage for the combined modality treatment. However, this approach for NSCLC reported so far has been disappointing, because of relative lack of effectiveness of the present CT.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

[Combination chemotherapy of CDDP and etoposide in advanced non-small cell carcinoma of the lung].

Twenty-seven patients with advanced and previously untreated non-small cell carcinoma of the lung received combination chemotherapy with CDDP (100 mg/m2 iv on day 1) and etoposide (100 mg/m2 iv on day 2, 4 and 6). Eleven partial responses were observed (response rate of 40.7%), and the median survival of patients was 44.4 weeks. Toxicity was tolerable with moderate myelosuppression. This combination chemotherapy should be recommended for further clinical trials.

Adult↗
PubMed1988

[A case of acute adult T-cell leukemia with long-term remission by cisplatin therapy].

A 37-year-old man was admitted because of general malaise, slight fever, pain in the knee joint and lower extremities, polydypsia, polyuria and skin lesion in September, 1985. The white blood cell count was 16,920/cmm with 41% of abnormal lymphoid cells with convoluted nuclei, which were compatible with adult T-cell leukemia (ATL). The serum calcium level was 15.1 mg/dl, serum LDH 307 IU/l, and the titer of anti-ATLA antibody in serum x 160. The cell surface phenotype of abnormal lymphocyte was OKT-3+, OKT-4+ and OKT-8-. Therefore the diagnosis of acute ATL was made. He was treated with cisplatin because VEPA therapy was not effective. About five months after the start of chemotherapy, he entered remission with almost complete disappearance of abnormal lymphocyte. The remission continued over twenty-nine months with maintenance therapy by cisplatin alone. The clinical course of this patient suggests that cisplatin could be applied to a case of ATL which is refractory to the conventional treatment.

Adult↗