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S Hisano

Publications and source records attributed to S Hisano.

At least 109 records · Page 6Linked to original sources

Axons containing neuropeptide Y innervate arginine vasopressin-containing neurons in the rat paraventricular nucleus. Dual electron microscopic immunolabeling.

Synaptic connections between neurons immunoreactive for arginine vasopressin (AVP) and axon terminals immunoreactive for neuropeptide Y (NPY) were found in the magnocellular part of the paraventricular nucleus (PVN) in the rat hypothalamus. In pre-embedding double immunolabeling, NPY axon terminals labeled with diaminobenzidine (DAB) reaction product established synaptic junctions on the perikarya and neuronal processes of AVP neurons labeled with silver-gold particles. Ultrastructural morphology of the neurons was more suitably preserved by a combination of pre- and post-embedding procedures. The presynaptic NPY terminals contained many small clear vesicles and a few cored vesicles, and DAB chromogen (immunoreaction product) was located on the surface of the vesicular profiles and on the core. The postsynaptic AVP neurons possessed many large secretory granules labeled with gold particles. At the synaptic junctions, small clear vesicles were accumulated at the presynaptic membrane, and the postsynaptic membrane was coated with a dense accumulation of fine electron dense particles. The perikarya also received synapses made by immuno-negative axon terminals containing many small clear vesicles and a few cored vesicles. These terminals were found more frequently than those containing NPY.

Animals↗

Asymptomatic haematuria and proteinuria: renal pathology and clinical outcome in 54 children.

In a mass screening programme, 54 children with haematuria and proteinuria were detected and evaluated by clinical findings and renal histology. IgA glomerulonephritis (GN) occurred in 29 patients, diffuse mesangial proliferative GN (DPGN) in 16, membranous GN (MGN) in 4, membranoproliferative GN (MPGN) in 3, and focal segmental glomerular sclerosis (FSGS) was seen in 2. Of the 35 children with proteinuria less than or equal to 1 g/m2 per day, 21 with IgA GN and 14 with DPGN had only mild to moderate glomerular changes. None of these children had developed renal impairment after a mean period of 6.5 years (range 5-10 years). On the other hand, 8 children with IgA GN, 2 with DPGN, 4 with MGN, 3 with MPGN, and 2 with FSGS had proteinuria that exceeded 1 g/m2 per day. The biopsy specimens from these children showed moderate to severe glomerular changes, and 7 of these children had hypertension or renal impairment during the period of evaluation. This study suggests that a poor outcome correlates with the level of proteinuria and the severity of renal pathology in children with haematuria and proteinuria.

Adolescent↗

Immunohistochemical approach to the functional morphology of the hypothalamic-hypophysial system.

Immunohistochemical studies at the light and electron microscopic levels have provided much information on functional morphology in the hypothalamic-hypophysial system. The present paper describes the immunohistochemical techniques available at present and their use to determine the localizations of neurons containing hypophysiotrophic substances, the co-storage of plural signals in these neurons, and the synaptic regulation of these neurons in rats.

Animals↗

Detection of pulmonary telangiectasia using dynamic pulmonary perfusion imaging in patients with liver cirrhosis.

Two cases of liver cirrhosis associated with marked hypoxemia are presented. Chest radiographs and cardiopulmonary function showed no abnormalities, except for the low diffusion capacity of carbon monoxide and slight elevation of the shunt ratio (20 and 6.2%, respectively), as estimated under conditions of 100% oxygen inhalation. Pulmonary perfusion imaging with Tc-99m macroaggregated albumin (MAA) revealed a significant radioisotope uptake in the lungs, brain, spleen, and both kidneys. Shunt ratios, estimated by the quantitative radionuclide method, were 60 and 68%, respectively. Dynamic pulmonary perfusion imaging revealed a gradual reduction in uptake in all areas of both lungs. The discrepancy of the shunt ratio between the two methods results from an abnormal dilatation of alveolar capillaries. The gradual reduction of radioactivity in areas of the lungs is caused by the passage of MAA particles through widened pulmonary capillaries.

Female↗

[Secondary leukemia (AML) with TcR beta rearrangement].

A 60-year-old female with fever and general lymphadenopathy was admitted to our hospital in 1979. By histological examination of cervical lymph node, she was diagnosed as B-cell malignant lymphoma, diffuse, large, stage IV B (Ann Arbor classification). In 1984, the complete remission of malignant lymphoma was observed after MOPP, COPP and VAPP chemotherapies. After 3 years, she was readmitted because of leukocytosis in which 64% immature abnormal cells were detected. By conventional cytological and cytochemical evaluations, the immature abnormal cells were identified as secondary AML cells with M 2 type (FAB), peroxidase (+), My 7 (+) and chromosomal abnormality; 48, X, -X, +4, -9, +21, del (1) (p 34), i (17 q), + M 1, + M 2. Analysis of Ig and TcR genes showed TcR-beta rearrangement. It has been reported that secondary leukemia frequently causes chromosomal abnormalities and therapy resistance. Ig gene and TcR gene analysis of secondary leukemia combined with chromosome examination, which has reported little, may be useful in predicting prognosis and therapy resistance.

Antineoplastic Combined Chemotherapy Protocols↗

High-dose methylprednisolone therapy for nephrotic syndrome in Henoch-Schoenlein nephritis.

Twelve patients with nephrotic syndrome (NS) in Henoch-Schoenlein (HS) nephritis were treated with a high dose of intravenous methylprednisolone (MP) on each of nine alternate days followed by oral prednisolone for 4 to 6 months. Renal biopsy was performed on 10 of the 12 patients. The glomerular change in 5 patients, which was accompanied by crescents and/or sclerosis, with NS and acute nephritic syndrome (ANS) at onset, was more severe than that of the other 5 patients with NS and hematuria at onset. The renal insufficiency or hypertension in these 5 patients with NS and ANS improved within 2 weeks on this MP therapy. After a mean follow-up period of 40.5 months, all patients except 2 revealed normal physical findings and renal function as well as urinary findings. Repeated biopsies in the 2 patients with NS and ANS at onset demonstrated an improved renal pathology in comparison with their initial biopsies. No severe side effects related to high-dose intravenous MP followed by oral prednisolone therapy were encountered in any of the patients. Our results suggest that high-dose intravenous MP therapy can lead to a favorable outcome in patients with NS in HS nephritis.

Adolescent↗

Suprachiasmatic nucleus neurons immunoreactive for vasoactive intestinal polypeptide have synaptic contacts with axons immunoreactive for neuropeptide Y: an immunoelectron microscopic study in the rat.

An electron microscopic study showed by using a dual immunolabeling technique that in the suprachiasmatic nucleus of the rat, axon terminals immunoreactive for neuropeptide Y (NPY) made synaptic contacts upon neurons immunoreactive for vasoactive intestinal polypeptide (VIP). Diaminobenzidine (DAB)-labeled NPY axon terminals made synaptic contacts on silver-gold-labeled VIP perikarya and dendritic processes. The presynaptic NPY terminals contained many small clear vesicles and a few cored vesicles labeled with DAB chromogen. At the synaptic portion, a symmetrical thickening of the pre- and post-synaptic membranes was evident.

Animals↗

Ultrastructural localization of immunolabeled substance P and methionine-enkephalin-octapeptide in the surface layer of the dorsal horn of rat spinal cord.

A preembedding dual immunolabeling technique and electron microscopy were utilized to demonstrate the localization of immunoreactive substance P and methionine-enkephalin-octapeptide (Enk-8) in ultrathin sections of the surface layer (laminae I and II) of rat spinal dorsal horn. The immunoreaction of Enk-8 was visualized as gold-toned silver particles and that of substance P as diaminobenzidine reaction products. Axonal terminals with immunoreactive substance P, and also unlabeled axonal terminals, formed synaptic junctions with the perikarya and dendritic processes of Enk-8-containing neurons. Dendritic profiles immunolabeled for substance P were synaptically linked with unlabeled axons but not with Enk-8-positive ones. Furthermore, it was found that Enk-8 axons and substance P axons terminated synaptically in juxtaposition to one another on the same immunonegative dendrites. Among the Enk-8-containing neurons axonal profiles also appeared to be synaptically associated with immunoreactive Enk-8 dendritic processes.

Animals↗

Light- and electron-microscopic evidence of costoring of immunoreactive enkephalins and substance P in dorsal horn neurons of rat.

The topographical localization of substance P (SP) and methionine-enkephalin-octapeptide (Enk-8) was examined immunohistochemically in the surface layer of the dorsal horn of rat cervical spinal cord. Although a few neurons were immunoreactive for Enk-8 in the intact animals, after an intracisternal administration of colchicine, immunoreactive Enk-8 neurons were numerous, and half of them indicated immunoreactivity also for SP. Some immunoreactive SP neurons appeared to show no immunoreactivity for Enk-8. Immuno-reactive nerve fibers, on the other hand, were numerous, and many of them contained both peptides. Electron-microscopic examination of the nerve fibers in tissue prepared by a freeze-drying procedure and stained by a postembedding procedure, revealed the costoring of both peptides in the same cored vesicles. The physiological significance of this costoring is discussed.

Animals↗

Ultrastructural evidence for neuronal regulation of growth hormone secretion.

The morphological substrate for the central mechanisms that control growth hormone (GH) release in the rat hypothalamus was investigated immunohistochemically by light and electron microscopy. In electron-microscopic studies, a dual immunolabeling technique was employed to demonstrate pairs of peptides, i.e. rat hypothalamic growth hormone-releasing factor (rhGRF) and somatostatin (SRIH), rhGRF and substance P (SP), and rhGRF and methionine-enkephalin-Arg6-Gly7-Leu8 (Enk-8), in different neuronal structures. Immunoreactivity of rhGRF was detected as silver-gold particles and those of the other substances as diaminobenzidine products by preembedding immunostaining procedures. In the external layer of the median eminence, axonal terminals immunolabeled for rhGRF and for SRIH showed the same pattern of distribution and close proximity. The neuronal inputs to GRF cell bodies in the arcuate nucleus were examined, and SRIH, SP and Enk-8 fibers with varicosities were found to form dense networks around the perikarya of GRF neurons, suggesting the presence of synaptic associations. Axonal terminals immunolabeled for SRIH, SP or Enk-8, and unlabeled terminals appeared to form coincidental synaptic junctions on GRF perikarya. These findings suggest that the central regulation of GH release occurs at the levels of the median eminence and the cell bodies.

Animals↗

Synaptic association between enkephalin-containing axon terminals and proopiomelanocortin-containing neurons in the arcuate nucleus of rat hypothalamus.

By employing an electron microscopic dual immunolabeling technique, a synaptic association between neurons containing immunoreactive adrenocorticotropin (ACTH) and axonal terminals containing immunoreactive methionine-enkephalin octapeptide (Enk-8) was found in the arcuate nucleus of the rat hypothalamus. The axonal terminals contained many small clear vesicles and some large cored vesicles. At the synaptic portions, membrane specialization was asymmetric.

Animals↗

Intragranular colocalization of arginine vasopressin and methionine-enkephalin-octapeptide in CRF-axons in the rat median eminence.

Ultrastructural appearances of axonal terminals containing corticoliberin (CRF) were examined in the rat median eminence prepared by a freeze-drying procedure. Immunolabeling was performed by using 5-, 8-, or 15-nm gold-antibody complexes for CRF, arginine vasopressin (VP) and methionine-enkephalin-octapeptide (Enk-8), singly or in combination. In intact animals, the CRF-containing secretory granules were only slightly labeled with gold-anti-VP or -Enk-8. In adrenalectomized rats, granules within single axons appeared to be labeled with all the immunogold complexes. This intragranular colocalization of the three antigens was confirmed by using three neighboring sections of the same axon terminals which were stained separately with each one of the antibodies and visualized with the avidin-biotin-peroxidase complex method. The granules labeled for CRF had decreased 9 days after adrenalectomy but had increased again by day 21, while those labeled for VP steadily increased after adrenalectomy. However, this did not correspond with the appearances of cell bodies in the paraventricular nucleus; the cell bodies labeled for both CRF and VP steadily increased in number and in stainability. By contrast, Enk-8 immunoreactivity in the axonal terminals and cell bodies was not affected by adrenalectomy. These findings suggest that although the three peptides could be released simultaneously from the axonal terminals, VP may play some special role in the expression of CRF activity.

Adrenalectomy↗

Immunohistochemical evidence of serotoninergic regulation of vasoactive intestinal polypeptide (VIP) in the rat suprachiasmatic nucleus.

By applying a double-immunolabeling technique to preembedded tissue preparations, we demonstrated the existence of serotoninergic innervation to neurons containing vasoactive intestinal polypeptide (VIP) in the rat suprachiasmatic nucleus (SCN). Immunoreactivity for serotonin and VIP was revealed by the presence of diaminobenzidine (DAB) reaction products and silver-intensified DAB reaction products, respectively; in a further stage, the silver grains were substituted with gold particles. DAB reaction products were precipitated on the surface of vesicular structures, while gold particles were scattered diffusely throughout the neuroplasma at various densities. Serotoninergic axons were numerous and closely packed together, occasionally forming synaptic junctions with gold-labeled VIP-containing neurons. At these synaptic junctions, small vesicular structures accumulated to form a coat under the presynaptic membrane, and the postsynaptic membrane was lined with a homogeneous accumulation of fine deposits. This postsynaptic apparatus varied in appearance; some parts were flat and thin, while others were of irregular thickness. Serotoninergic fibers also formed synaptic junctions with unidentified neurons, in which postsynaptic membrane specialization was also observable. As VIP-containing neurons are known to be synapsed by somatostatin (SRIH)-containing neurons, their regulation must involve both serotonin and SRIH at least.

3,3'-Diaminobenzidine↗

Immunohistochemical studies on the roles of substance P in the rat hypothalamus: possible implication in the hypothalamic-hypophysial-gonadal axis.

The hypothalamic neurons containing substance P (SP) were examined immunohistochemically in rats with a normal estrous cycle or persistent estrus (PE), in pregnancy and in lactating state. In PE animals, the neurons increased in number 1 week after ovariectomy, but then decreased and disappeared. During pregnancy, there were many SP neurons at an early stage but later they gradually decreased in number and disappeared. Consequently, during lactation no SP neurons were evident. The external layer of the median eminence (ME) contained many immunolabeled nerve terminals. In the ME prepared by a freeze-drying technique and immunostained with gold-labeled IgG by the postembedding procedure, the immunolabeled terminals were seen to contain large cored vesicles (50-100 nm) labeled with gold and unlabeled small clear vesicles (30-50 nm). In normal cycling rats, the terminals contained large cored vesicles in diestrus, small clear vesicles in estrus, and both in proestrus. In PE rats, the terminals contained only small clear vesicles, but the cored vesicles appeared after ovariectomy. In the early stage of pregnancy, the terminals contained only small clear vesicles, but the large cored vesicles appeared in late pregnancy and during lactation. These findings present further evidence that the hypothalamic SP neurons are involved in the hypothalamic-hypophysial-gonadal axis in rats.

Animals↗

Differential immunolabeling for electron microscopy of diverse peptidergic neurons.

We describe a simple and reliable method for differential immunolabeling of pre- and post-synaptic signal peptides at the ultrastructural level. Hypothalamic tissues of rats, including the suprachiasmatic nucleus, were cut on a Vibratome. Visualization of the immunolabeling of somatostatin (SRIH) and vasoactive intestinal polypeptide (VIP) was performed with avidin-biotin-peroxidase-diaminobenzidine (DAB). The end product of the DAB to VIP was further silver-intensified in a physical processing using silver nitrate, and the silver grains were finally substituted for gold. DAB-labeled SRIH fibers synapse on gold-labeled VIP perikarya and dendrites in the suprachiasmatic nucleus.

Animals↗

Intragranular colocalization of CRF and Met-Enk-8 in nerve terminals in the rat median eminence.

The ultrastructural localizations of rat corticoliberin (rCRF) and methionine-enkephalin octapeptide (Met-Enk-8) in the external layer of the rat median eminence were examined by double-immunogold labeling with anti-rCRF and anti-Met-Enk-8 sera labeled with small-sized (Gs) and medium-sized (Gm) gold particles, respectively. Two types of immunolabeled terminals were distinguished: one type with small granules (70 nm) labeled with Gs, and the other with large granules (100 nm) labeled with Gm. In both types, however, some granules were labeled with both Gs and Gm.

Animals↗