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Y Sano

Publications and source records attributed to Y Sano.

At least 379 records · Page 21Linked to original sources
PubMed1983

Immunohistochemical demonstration of serotonin neurons in the central nervous system of the turtle (Clemmys japonica).

The location of the somata, course of the main tracts, and fiber distribution of the serotonin neurons in the turtle brain were studied using the peroxidase-antiperoxidase (PAP) immunohistochemical method with antibodies against serotonin (5-hydroxytryptamine). The somata of the serotonin neurons were distributed in the reticular formation of the brainstem from the mesencephalon to the lower medulla level and in a resticted region of the hypothalamus, viz. the paraventricular organ (PVO). In the PVO the serotonin neurons were seen to have the appearance of cerebrospinal fluid-contacting neurons. Analysis of serial sections cut in the frontal and sagittal planes revealed a widespread distribution of the serotonin immunoreactive fibers in the turtle brain. Prominent concentrations of the serotonin immunoreactive fibers were found in the lateral portion of the striatum, the ventral portion of the septum, the nucleus corporis geniculati lateralis, the nucleus pretectalis, the nucleus isthmi parvocellularis, the optic tectum, and the lateral edge of the reticular formation of the brainstem. Ascending and descending serotonin pathways could be defined: the ascending pathway originated mainly from the nucleus profundus mesencephali caudalis, nucleus lemnisci lateralis, nucleus reticularis isthmi and, less prominently, from the nucleus raphe superior pars lateralis, and the descending pathway arose predominantly from the nucleus raphe inferior. The fibers of the ascending pathway projected widely in the prosencephalon and mesencephalon, via the medial forebrain bundle. The descending pathway ran through the ventral and lateral portion of the medulla oblongata and spinal cord.

Animals↗
PubMed1983

Motoneurons innervating the cremaster muscle of the rat are characteristically densely innervated by serotoninergic fibers as revealed by combined immunohistochemistry and retrograde fluorescence DAPI-labelling.

The lumbar spinal cord of the rat was studied by combined retrograde fluorescent labelling with 4',6-diamidino-2-phenylindole-2HCl (DAPI) and immunoperoxidase procedure using serotonin antiserum. A peculiar small neuronal group endowed more densely than other anterior horn neurons with serotonin-like immunoreactive fibers was recognized in the anterior column of lumbar segments L1-L2. At the same time, this small nucleus was shown to contain the motoneurons innervating the cremaster muscle by means of retrograde labelling with DAPI. It is tentatively suggested that the bulbospinal descending serotonin system is particularly intimately connected with the function of the cremaster muscle.

Animals↗
PubMed1983

Serotonin distribution in the circumventricular organs of the rat. An immunohistochemical study.

Serotonin-immunoreactive structures in the circumventricular organs (organum vasculosum laminae terminalis, subfornical organ, subcommisural organ and area postrema) of the rat were demonstrated using a modified peroxidase-antiperoxidase immunohistochemical method. Various densities of serotonin fibers were demonstrated in all four circumventricular organs; however, serotonin-positive cells were evident in the area postrema only after nialamide treatment. Serotonergic supraependymal fibers were observed on the surface of the organum vasculosum laminae terminalis and that of the subfornical organ, but not on the subcommissural organ and area postrema. The organ, but not on the subcommissural organ and area postrema. The serotonergic plexus of the basal portion of the subcommisural organ was considered to be continuous with the supraependymal plexus.

Animals↗
PubMed1983

Serotonergic innervation on the motoneurons in the mammalian brainstem. Light and electron microscopic immunohistochemistry.

A comparative study of serotonergic innervation on motoneurons in the brainstem of various mammals (mouse, rat, guinea pig, dog, cat and monkey) was carried out using a sensitive immunohistochemical method. Except for the extraocular muscle nuclei, the motor nuclei of the cranial nerves received rich inputs from serotonin neurons, in all species examined--rodent, carnivore and primate. The motoneurons of the monkey were innervated by varicose serotonin fibers, in a manner different from that of other species, i.e. their cell bodies and proximal dendrites were tightly encircled by a large number of serotonin-containing varicose fibers. At the ultrastructural level, a predominant population of axosomatic contacts was confirmed in the cranial motor nuclei of the monkey, particularly in the nucleus ambiguus.

Animals↗
PubMed1983

Immunohistochemical identification of Lucifer Yellow-labeled neurons in the rat supraoptic nucleus.

An attempt was made to identify Lucifer Yellow-labeled neurons in the rat supraoptic nucleus as vasopressin-containing neurons, by means of a combination of immunoperoxidase histochemistry and iontophoretic single cell-injection. We came to the conclusion that the fluorescent dye does not diminish the immunoreactivity of vasopressin in the magnocellular neurons. This newly developed method, along with its modifications, should prove to be quite useful for electrophysiological and morphological studies on the neuropeptide-releasing neurons in the mammalian neuroendocrine system.

Animals↗
PubMed1983

Identification of EC cells in the human intestine: a comparative study between immunohistochemical and silver impregnation techniques.

Selective immunohistochemical identification of enterochromaffin (EC) cells in the human duodenum and colon has been carried out, using a highly specific rabbit antiserotonin serum and the unlabeled peroxidase-antiperoxidase complex (PAP) technique. The sensitivity of the reaction, and morphology of the cells, were compared with those of the argentaffin or argyrophil reactions on the same sections at the light microscopic level. All argentaffin cells were argyrophil and PAP positive, but a small number of PAP-positive cells were neither argentaffin nor argyrophil. In addition, a few EC cells stained by the PAP method were shown to be argyrophil but not argentaffin. The PAP method permitted the clear morphological identification of the entire cell, particularly its cytoplasmic processes, whereas both the argentaffin and argyrophil reactions were basically seen in the basal regions of the cells and often failed to demonstrate the cytoplasmic processes. These findings indicate that the immunohistochemical method is more sensitive and advantageous than silver impregnations for the selective demonstration of EC cells.

Chromaffin System↗
PubMed1983

Immunohistochemical demonstration of serotonin-containing CSF-contacting neurons in the submammalian paraventricular organ.

The distribution and morphological aspects of the serotonin-containing neurons in the paraventricular organ of the carp, frog, turtle and chicken were studied by means of an immunoperoxidase technique using serotonin antiserum. In all species the serotonin-containing neurons were seen to have the appearance of the CSF-contacting neurons and to be distributed in the pars ependymalis and the pars hypendymalis of the organ. Particularly, in the frog, the serotonin-containing CSF-contacting neurons, mostly bipolar in shape, were also observed in the pars distalis. Their proximal processes protruded into the ventricular lumen through the ependymal layer with a globular- and triangular-shape. The distal processes projected ependymofugally to the pars distalis and formed a fine plexus in the neuropil of this part. The density of the serotonin fibers in the pars distalis was greater in the carp than in the other species.

Animals↗
PubMed1983

Effects of ovarian steroids on the 17 alpha-hydroxylase activity toward progesterone in a human ovarian follicle at the late follicular phase.

The dominant follicle at the late follicular phase was obtained from a human ovary, the follicular wall was homogenized and centrifuged at 800 g. Then, the supernatant fluid was incubated with [14C]-progesterone and the radioactive products were quantitated. 17-Hydroxyprogesterone, 16 alpha-hydroxyprogesterone and androstenedione were identified under the present experimental conditions. The apparent KM value of the 17 alpha-hydroxylase toward progesterone was 0.19 +/- 0.01 microM. Various ovarian steroids (17-hydroxyprogesterone, 20 alpha-hydroxy-4-pregnen-3-one. 16 alpha-hydroxyprogesterone, androstenedione, testosterone, estrone and estradiol-17 beta) were tested for their effects on this hydroxylase activity. Among them, 20 alpha-hydroxy-4-pregnen-3-one and 17-hydroxyprogesterone inhibited on the enzyme activity, significantly. They acted competitively and their Ki values were 0.23 microM for 20 alpha-hydroxy-4-pregnen-3-one and 0.54 microM for 17-hydroxyprogesterone.

Adult↗
PubMed1983

Decreased mononuclear cell beta-adrenergic receptors in bronchial asthma: parallel studies of lymphocyte and granulocyte desensitization.

To assess the interaction of bronchial asthma and beta-agonist drugs, beta-adrenergic receptors were measured in human mixed leukocyte, mononuclear cell, and polymorphonuclear leukocyte cell membranes simultaneously. The densities and affinities of beta-adrenergic receptors were determined, by Scatchard analysis, with a potent beta-antagonist 125I-hydroxybenzylpindolol (125I-HYP) and compared among 12 nonatopic controls (group I), 13 mild asthmatics not taking drugs (group II), and eight asthmatics receiving long-term beta-agonist therapy (group III). Our findings were as follows. (1) Asthmatics not taking drugs (group II) have significantly lower mean mononuclear leukocyte beta-adrenergic receptor density (p less than 0.05) but no significant difference in mean polymorphonuclear leukocyte beta-adrenergic receptor density than the control group. (2) Asthmatics receiving long-term beta-agonist treatment (group III) had significantly lower mean beta-adrenergic receptor density in all three cell fractions (p less than 0.05). (3) Group I and II females had a higher mean beta-adrenergic receptor density in mixed leukocyte and polymorphonuclear cell fractions than males (p less than 0.05). (4) Terbutaline sulfate clearly caused desensitization of beta-adrenergic receptors in human leukocyte membranes in vivo. These results show that beta-adrenergic receptor density is influenced by cell type, beta-adrenergic agonist administration, and sex; they also show that bronchial asthma itself is associated with lower lymphocyte beta-receptor density.

Administration, Oral↗
PubMed1983

The relative resistance of non-cycling cells in 9L multicellular spheroids to spirohydantoin mustard.

Surviving fractions of 9L spheroid cells treated with 1.5, 3.0 and 6.0 micrograms/ml of spirohydantoin mustard (SHM) decreased when assayed 6 hr after treatment but increased thereafter. Flow cytometric analysis showed that exponentially growing 9L monolayer cells treated with SHM accumulated at the G2/M border within 24 hr. Cells dissociated from spheroids treated with 3 and 6.0 micrograms/ml of SHM accumulated at the G2/M border during the first 24 hr after treatment and remained there for the next 12 hr. However, 50% of the cells remained at the 2C DNA peak. Spheroid cells with 2C DNA content 24 hr after treatment were assumed to be non-cycling cells at the time of treatment, and cells that accumulated at the G2/M peak appeared to be cycling cells at the time of treatment; approximately 50% of cells in untreated 9L spheroids are in the noncycling pool. G1 and/or early S phase 9L cells in exponential growth elutriated immediately after treatment with SHM had significantly lower (P greater than 0.001) plating efficiencies than 9L cells in S and G2/M phases. When spheroids were dissociated, elutriated and plated for colony-forming efficiency 24 hr after treatment with 3 micrograms/ml of SHM, fractions enriched in 2C DNA content had significantly higher (P greater than 0.001) plating efficiencies than elutriated cells enriched in 4C DNA. These results indicate that SHM is less effective against non-cycling 9L spheroid cells with 2C DNA content than against cycling 9L spheroids cells.

Animals↗
PubMed1983

Immunohistochemical study on the distribution of serotonin-containing cell bodies in the brain stem of the dog.

The distribution of serotonin-containing neurons in the brain of the dog was studied by use of PAP immunohistochemistry. The lower brain stem was endowed with extensively scattered serotonergic cell bodies, a large portion of which was located in the raphe nuclei. At the same time, prominent distribution of serotonergic neurons in lateral areas outside the raphe nuclei was also demonstrated. Our observations on the brain stem were, in principle, consistent with those on rats, cats and monkeys, with only minor differences.

Animals↗
PubMed1983

Two types of oxytocin and vasopressin nerve fibers in the intra- and extrahypothalamic neuronal systems as revealed by immunohistochemistry.

The oxytocin and vasopressin nerve fibers in the intra- and extrahypothalamic neuronal systems of several mammalian brains are immunohistochemically demonstrated using a modified peroxidase-antiperoxidase technique. The axonal processes of these peptidergic neurons are classified into thick and thin beaded fibers. Thick beaded fibers were preferentially distributed in the hypothalamo-neurohypophysial tract and in some circumventricular organs, with termination on the blood vessels. Thin beaded fibers were found in various extrahypothalamic areas and these terminals were in the vicinity of the neuronal somata of such areas. This report suggests that there are at least two different functions concerning neurotransmission in the oxytocin and vasopressin neuronal system.

Animals↗
PubMed1983

Immunohistochemical identification of the corticotropin releasing factor (CRF)-containing nerve fibers in the pig hypophysis, with special reference to the relationship between CRF and posterior lobe hormones.

Immunoperoxidase histochemical investigations on pig hypophysis show that CRF immunoreactive nerve terminals are distributed around the blood vessels in the posterior lobe, particularly in its proximal part adjacent to the intermediate lobe. CRF immunoreactive nerve fibers are also seen in the intermediate lobe. The distribution of the CRF-containing nerve in the posterior lobe was found to be similar to that of the vasopressin-containing nerve terminals. The functional significance of the presence of CRF-containing nerve fibers representing a new component of the hypothalamo-hypophyseal neurosecretory system is discussed.

Animals↗
PubMed1983

Immunohistochemical studies on the peptidergic nerve fibers in the pineal organ of the dog.

The distribution of vasopressin-, oxytocin- and LHRH-containing nerve fibers in the pineal organ of the dog was demonstrated by use of the peroxidase-antiperoxidase immunohistochemical technique. These neuropeptide-containing fibers penetrated through the pineal stalk from the brain, mainly from the posterior commissural region, into the pineal organ. The vasopressin fibers were the most prominent in number, oxytocin fibers and LHRH fibers were the least. Most of these fibers were found in the proximal part of the pineal organ, but some of them were also observed in the distal part. These peptidergic fibers were distributed not only in the perivascular spaces but among the parenchymal cells.

Animals↗
PubMed1983

Immunohistochemical observation of serotonin neurons in newborn mouse and rat brainstem cultures.

Serotonin neurons in newborn mouse and rat brainstem cultures were studied by peroxidase-antiperoxidase immunohistochemistry using a serotonin antibody. The intensity of the immunohistochemical reaction in the neuronal somata decreased gradually with time and was hardly detectable after one month of culturing. On the other hand, the immunoreactivity of the processes noted at the early stages later on became more intense and covered the full extent of the fibers. From the early stages of the cultures, the axon of each serotonin neuron formed not only a network by branching, but also a true anastomosis with the axonal networks of the other serotonin neurons.

Animals↗
PubMed1983

Distribution of serotonergic neurons in the central nervous system: a peroxidase-antiperoxidase study with anti-serotonin antibodies.

Distribution of serotonin (5-HT) neurons in the central nervous system (CNS) of various vertebrates was investigated with a highly sensitive immunohistochemical technique. Antibodies were raised in rabbits against an antigen prepared by coupling 5-HT to bovine thyroglobulin. 5-HT neurons were found to be distributed more widely and densely than has been heretofore described. Serotonergic neuronal somata are organized according to certain basic patterns, but there are interspecific differences with regard to the distribution of 5-HT fibers. The processes of 5-HT neurons form a dense plexus by ramification and anastomosis in almost all areas of the CNS, including the ventricular surfaces. In the light of our observation, Golgi's reticular theory may have to be revised.

Animals↗