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S Shiosaka

Publications and source records attributed to S Shiosaka.

At least 73 records · Page 4Linked to original sources
PubMed1990

Electron microscopic observation of calcitonin gene-related peptide-like immunoreactivity in the organ of Corti of the rat.

Calcitonin gene-related peptide (CGRP)-like immunoreactive (CGRP-IR) nerve terminals in the organ of Corti of rats were studied by light and electron microscopy. Surface preparation of the organ of Corti were immunostained using anti-CGRP antiserum for avidin-biotin immunohistochemistry. Dense CGRP-IR fiber bundles were observed by light microscopy in the inner spiral bundles, tunnel spiral bundles and outer spiral bundles. Electron microscopic analysis indicated that CGRP-IR fibers belong to efferent nerves. In the inner spiral bundles, the CGRP-IR fibers showed a direct contact mainly with non-immunoreactive afferent fibers. Some CGRP-IR nerve endings in the inner spiral bundles formed contacts directly with inner hair cells. In the outer spiral bundles, CGRP-IR fibers formed synaptic contacts exclusively with the outer hair cells. It should be noted that the number of synapses of CGRP nerve endings with outer hair cells varied depending upon the sub-row: a falling gradient in number occurred along the inner-outer axis. Our results suggest that CGRP acts as an efferent neuromodulator in the organ of Corti.

Animals↗
PubMed1990

Presence of sex difference of cytochrome P-450 in the rat preoptic area and hypothalamus with reference to coexistence with oxytocin.

Localization of female type cytochrome P-450 (F1) in the preoptic area and hypothalamus of the rat was examined immunocytochemically using antiserum against purified hepatic P-450 (F1). This antiserum recognizes both P-450 (F1) and P-450 (M3). Western immunoblotting using the antiserum demonstrated that female rat brain contains P-450 (F1) but not P-450 (M3), since microsomes from the brain and liver displayed only one immunoreactive band at 50 kD, coinciding with that of P-450 (F1) purified from female rat liver. On the other hand, the male brain has P-450 (M3) but not P-450 (F1), as liver- and brain-derived microsomes produced single band at 49 kD, which represents a mol. wt. identical to that of P-450 (M3) extracted from male rat liver. These results indicate that P-450 (F1)-like immunoreactivity (LI) occurs in the female rat brain, while P-450 (M3)-LI takes place in the male rat brain. Immunocytochemical analysis further demonstrated the detailed cellular localization of these two P-450-LIs in the preoptic area and hypothalamus of female and male rats. Localization of P-450 (F1)-LI in the female rat hypothalamus resembled that of P-450 (M3)-LI in the male rat hypothalamus. Magnocellular neurosecretory neurons in the paraventricular nucleus and supraoptic nucleus were labeled and were found to contain oxytocin but lack vasopressin when serial sections of these areas were analyzed. In addition, groups of immunoreactive cells were seen in the median preoptic nucleus, medial and lateral preoptic area, caudal portion of the bed nucleus of the stria terminalis, lateral hypothalamus at the level of the paraventricular nucleus, periventricular zone from the preoptic area to the paraventricular nucleus, and parvocellular portion of the paraventricular nucleus.

Animals↗
PubMed1990

Transient expression of somatostatin mRNA in the auditory system of neonatal rat.

Postnatal changes of preprosomatostatin mRNA expression in the rat auditory system were examined using in situ hybridization histochemical techniques. It was found that during postnatal days 1 and 2 most of the neurons in the dorsal and ventral cochlear nuclei, and large numbers of neurons in the inferior colliculus, paralemniscal nucleus, and lateral lemniscal nucleus, expressed somatostatin mRNA with a strong intensity. During postnatal development a marked decrease in the number and intensity of neurons expressing somatostatin mRNA was seen. These findings suggested that somatostatin was actively produced in the cochlear nuclei at a very early stage but that production later became reduced or ceased during postnatal ontogeny.

Aging↗
PubMed1989

An attempt to cause the selective loss of the cholinergic neurons in the basal forebrain of the rat: a new animal model of Alzheimer's disease.

In the present study, we attempted to develop a new animal model of Alzheimer's disease. Injections of a nerve growth factor (NGF)-diphtheria toxin conjugate into the cerebral cortex resulted in a marked ipsilateral reduction of cholinergic neurons in the horizontal limb of the diagonal band and basal magnocellular nucleus of rats. No effects could be seen in the cholinergic neurons located in the laterodorsal tegmental nucleus intrinsic cortical cholinergic neurons, and catecholaminergic locus coeruleus neurons. Injections of the conjugate into the caudoputamen failed to cause changes in the striatal cholinergic neurons. Since our method could selectively reduce cholinergic neurons in the basal forebrain without damage to the non-cholinergic neurons or passing fibers in this nucleus, this animal model method seems to be very useful in analyzing the pathogenesis of Alzheimer's disease or in examining the function of acetylcholine in the cholinergic neurons of the basal forebrain.

Alzheimer Disease↗
PubMed1989

Gap junction protein in rat hippocampus: light microscope immunohistochemical localization.

An affinity-purified antibody against a 27-kD rat liver gap-junctional protein (GJP) was used to determine the distribution of GJP immunoreactivity in sections of rat hippocampus. Four heterogeneously distributed GJP-immunostaining patterns were observed. The two most common were punctate immunoreactive elements ranging in size from 0.3 to 0.7 microns and networks of immunoreactive varicose fibers coursing in a variety of directions within the various hippocampal layers and ranging in length from a few microns up to 200 microns. The density of punctate immunostaining was highest within a portion of the stratum pyramidale, at the border between the stratum pyramidale and stratum oriens, and at the border between the molecular and granule cell layers of the dentate gyrus. Moderate to low densities were observed in other hippocampal areas. Immunoreactive fibers were most concentrated within the border portions of the stratum pyramidale and oriens, moderately distributed in the stratum radiatum and the remaining part of the stratum oriens, and sparse in the alveus. In the dentate gyrus, fiber networks were most evident at the border between the granule cell and molecular layers and very unevenly distributed in the molecular layer. The two other patterns observed included intense filamentous immunostaining within a small number of neuronal perikarya located mainly in the stratum pyramidale of areas CA2 and CA3, but rarely in area CA1 or the dentate gyrus, and diffuse immunostaining of small cell bodies dispersed throughout the hippocampus but most numerous in the vicinity of the stratum pyramidale and in the alveus. All of these immunostaining patterns were seen at all rostrocaudal hippocampal levels. These results suggest that if GJP-immunoreactive fibers and neurons observed in the hippocampus have the capacity to form gap junctions, then electrotonic transmission may constitute an important means of information processing within this structure.

Animals↗
PubMed1989

Gap junction protein in rat hippocampus: correlative light and electron microscope immunohistochemical localization.

Immunohistochemical techniques and an affinity-purified antibody directed against the 27-kD gap-junctional protein (GJP) from rat liver were used to determine the ultrastructural localization of GJP in the rat hippocampus. At the light microscope level, dense GJP immunoreactivity having a stringlike appearance was seen in a very small percentage of medium-sized neuronal somata located in the stratum pyramidale, and diffuse immunostaining was seen in many small cell bodies in the stratum pyramidale, stratum oriens, and the alveus. Abundant GJP-immunoreactive (GJP-IR) varicose fibers were observed in the strata pyramidale, radiatum, and oriens but were less concentrated in the alveus. Numerous punctate GJP-IR elements were observed in all hippocampal layers. Upon EM analysis, GJP-IR neuronal somata in the stratum pyramidale were found to be, without exception, nonpyramidal neurons as judged by such distinguishing features as their fusiform perikarya, indented nucleus, and well-developed rough endoplasmic reticulum (RER). Immunostaining within these cells was largely localized to the Golgi apparatus and associated vesicular components. Small, diffusely GJP-IR cells were identified ultrastructurally as protoplasmic and fibrous astrocytes. Immunostaining within these cells was localized to the Golgi apparatus, RER, and small, ribosomelike bodies 15-25 nm in diameter. Among neuronal processes GJP immunoreactivity was found within dendrites, axons, and axonal terminals. The latter structures contained numerous GJP-IR vesicles having an average diameter of about 40 nm. A frequent observation indicating some degree of specificity of the anti-GJP antibody employed here was immunostaining of typical gap junctions between dendrites and, more commonly, between processes of glial cells. Occasionally, however, GJP-IR dendrodendritic, axodendritic, and axoaxonic contacts were found that could be considered, at best, as being gap-junction-like (gj-L). In these cases, asymmetric immunostaining of adjacent plasma membranes forming gj-L structures was not uncommon. These results confirm the existence of gap junctions between dendrites in the rat hippocampus and demonstrate that GJP immunoreactivity on cytoplasmic membranes is restricted either to typical neuronal and glial gap junctions or to gj-L structures at circumscribed sites of contact between various types of neuronal elements where GJP may contribute to a novel mechanism of neural communication.

Animals↗
PubMed1989

Co-localization of adrenergic receptors and vitamin-D-dependent calcium-binding protein (calbindin) in the dopaminergic amacrine cells of the rat retina.

Using antisera against tyrosine hydroxylase (TH) and purified beta 2-adrenergic receptors (beta 2-AdR), we found that TH- and AdR-like immunoreactivities coexisted in large amacrine cells. These findings indicated an association between dopamine-containing amacrine cells and adrenergic amacrine cells. The present study also showed that amacrine cells with TH-like immunoreactivity have vitamin-D-dependent calcium-binding protein (calbindin, 27,000 kDa)-like immunoreactivity as well, suggesting that calbindin plays an important postsynaptic role in dopaminergic amacrine cells.

Animals↗
PubMed1989

In situ hybridization analysis of the somatostatin-containing neuron system in developing cerebellum of rats.

We used in situ hybridization histochemistry to examine the postnatal development of the somatostatin (SRIF) synthesizing system in the cerebellum of rats. There are numerous hybridizing neurons from 1 to 9 days after birth. These occur throughout the cerebellum including the developing medulla and cortex except in the external granular cell layer. The lateral cerebellar nucleus also contains SRIF gene-containing cells. The intensity of the signals for SRIF mRNA in the cerebellum decreases with age. There is a drastic decrease in SRIF mRNA in the lateral cerebellar nucleus. SRIF cells cannot be detected in the lateral cerebellar nucleus of adult rats, whereas a small, yet significant number of SRIF cells are scattered in the cerebellar medulla. However, the cerebellum of adult rats still contains a significant number of labeled cells in the granular cell layer, although the intensity for SRIF mRNA decreases from 14 days after birth to adulthood. SRIF gene-expressing cells in the cerebellar cortex are located primarily in the granular cell layer and appear to correspond to Golgi cells judging from their characteristic features. These results are consistent with our previous immunohistochemical study on the decrease of SRIF immunoreactivity in the cerebellum of adult rats. These findings, together with a recent study of transient SRIF receptor-expressing cells in the developing cerebellum suggest that SRIF acts during cerebellar development.

Aging↗
PubMed1988

Adrenal medullary cells transmute into dopaminergic neurons in dopamine-depleted rat caudate and ameliorate motor disturbances.

Adrenal medullary cell suspensions, derived from newborn rats (postnatal day 1-6), were implanted into the head of the caudate nucleus in 35 rats with unilateral 6-hydroxydopamine (6-OHDA) lesions in the nigrostriatal dopamine (DA) pathway. Behavioral recovery from Met-amphetamine induced circling, cell growth and morphological features (tyrosine hydroxylase positive cells), and release of adrenaline (Ad), noradrenaline (NA), DA, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were investigated for 40 weeks after transplantation. Met-amphetamine induced circling decreased significantly in 43% (15/35) of the rats. The decrease was concurrent with transmutation of the tyrosine hydroxylase-like immunopositive (THLI) cells into mature neurons that had abundant elongated neurites with varicosities and synapses on neuronal elements in the host caudate. In the absence of behavioral recovery (57%, 20/35) THLI cells were very scant. DA, DOPAC and HVA were reduced more than 90% in perfusates collected by in vivo dialysis from the striata of the animals that were not improved by transplant. These levels recovered to 20-50% of controls in animals whose behavior recovered. Ad and NA were not detected in the perfusates of either recovered or non-recovered animals. The results suggest that some grafted adrenal medullary cells transform into dopaminergic neurons and the release of DA from these grafted cells functionally affects behavior improvement for at least 40 weeks.

Adrenal Medulla↗
PubMed1988

Further observations on the relationship between adenosine deaminase-containing axons and trigeminal mesencephalic neurons: an electron microscopic, immunohistochemical and anterograde tracing study.

The somas of primary afferent neurons in the mesencephalic nucleus of the trigeminal nerve in rat have a dense investment of axons immunoreactive for the enzyme adenosine deaminase. We previously suggested that these axons may originate from adenosine deaminase-immunoreactive neurons located in the tuberomammillary nucleus of the hypothalamus [Nagy et al. (1986) Neuroscience 17, 141-156]. Anterograde tracing and immunohistochemical techniques were used to investigate this possibility further. In addition, the appearance of adenosine-immunoreactive axons and the nature of their interactions with mesencephalic neurons was examined ultrastructurally. After injections of either Phaseolus vulgaris-leucoagglutinin or wheat germ agglutinin-horseradish peroxidase into the region of the tuberomammillary nucleus, punctate deposits of anterogradely transported tracer, detected by immunoperoxidase methods, were seen surrounding mesencephalic neurons. In sections immunostained for tracer and adenosine deaminase by double immunofluorescence, some fibres in the periaqueductal gray matter and around Mes V somas were found to be labelled for both the lectin and the enzyme. Ultrastructurally, only a single morphological class of adenosine deaminase-immunoreactive axons adjacent to, or indenting the cytoplasmic membranes of, large somas in the mesencephalic nucleus could be recognized; they were varicose and contained relatively large immunoreactive vesicles ranging in diameter from 45 to 70 nm. Occasionally, thin processes of these axons could be traced back to small adenosine deaminase-positive neuronal cell bodies located not within the tuberomammillary nucleus, but rather, within the periaqueductal gray matter. In serial ultrathin sections, membrane specializations resembling synaptic junctions were sometimes seen at points where mesencephalic somas were in contact with adenosine deaminase-immunoreactive terminals. Somas within the mesencephalic nucleus also formed such junctions with non-immunoreactive boutons which were morphologically different from, and often seen in close proximity to, those containing adenosine deaminase. These results indicate that in addition to possible afferents from the tuberomammillary nucleus, primary sensory somas within the mesencephalic nucleus are also associated with axonal processes originating from adenosine deaminase-positive neurons located within the periaqueductal gray matter. The infrequent synaptic contacts between these somas and adenosine deaminase-positive axons, despite their close anatomical arrangement, is suggestive of a diffuse endocrine or neurocrine type of axonal relationship with mesencephalic somas or with the n

Adenosine Deaminase↗
PubMed1987

Distribution of substance P-like immunoreactive structures in the brainstem of the adult human brain: an immunocytochemical study.

The distribution of substance P-like immunoreactive (SPI) structures in the brainstem of the adult human was investigated by the avidin-biotinylated peroxidase complex method for immunocytochemistry. SPI structures were widely distributed in the brainstem, and particularly dense in the substantia nigra, peripheral portions of the colliculus inferior, central gray matter, parabrachial area, nucleus dorsalis tegmenti of Gudden, nucleus reticularis tegmenti pontis, nucleus tractus solitarii, nucleus dorsalis motorius nervi vagi, and nucleus tractus spinalis nervi trigemini.

Aged↗
PubMed1987

Nigrostriatal dopamine neurons receive substance P-ergic inputs in the substantia nigra: application of the immunoelectron microscopic mirror technique to fluorescent double-staining for transmitter-specific projections.

A direct synaptic contact between nigrostriatal dopamine neurons and substance P axons in the substantia nigra was demonstrated using the immunoelectron microscopic mirror technique combined with the fluorescent double-staining method for transmitter-specific projections. Substance P-immunoreactive terminals were found to make synaptic contact with nigral cells exhibiting tyrosine hydroxylase immunoreactivity and retrograde fluorescent labeling following injection of biotinylated lectin into the neostriatum. It appears that substance P afferents directly affect nigrostriatal dopamine neurons in the substantia nigra via the synaptic contacts.

Animals↗
PubMed1987

Origin of leucine-enkephalin fibers and their two main afferent pathways in the bed nucleus of the stria terminalis in the rat.

The destruction of the central amygdaloid nucleus (Ce), which contains a large group of neurons with leucine-enkephalin (L-ENK)-like immunoreactivity (L-ENKI), resulted in a marked ipsilateral reduction of these fibers in the bed nucleus of the stria terminalis (BST) suggesting that L-ENKI neurons in the Ce project ipsilaterally to the BST. This was supported by the finding that injection of biotin-wheat germ agglutinin into the BST labeled many neurons in the Ce. Simultaneous staining with antiserum showed that some of these neurons are L-ENKI. The L-ENKI fibers from the Ce reach the BST via two pathways; one from the venral amygdalofugal pathway (VA), which terminate in the ventral subdivision of the BST pars lateralis (BSTL), and the other from the stria terminalis (ST), which terminates in the lateral subdivision of the BSTL, because accumulation of L-ENKI structures appeared in the axons of these two systems on the amygdaloid side, transection or destruction of the ST alone caused only a slight reduction of ENKI fibers in the lateral subdivision of the BSTL ipsilaterally and transection or destruction of VA alone markedly reduced the number of L-ENKI fibers in the ventral subdivision of the ipsilateral BSTL. Thus, the VA L-ENKI fiber system is the major source of L-ENKI fibers in the ventral subdivision, while the ST L-ENKI fiber system is a minor source of the L-ENKI fibers in the lateral subdivision. The presence of an intrinsic L-ENKI system in the BST which may innervate the lateral subdivision was also suggested.

Afferent Pathways↗
PubMed1987

Distribution of cholinergic neurons and fibers in the hypothalamus of the rat using choline acetyltransferase as a marker.

The distribution of choline-acetyltransferase-like immunoreactive structures in the rat hypothalamus and preoptic area was examined by using avidin-biotin immunocytochemistry. We found that the hypothalamus is richly innervated by the cholinergic neuron system. Sites containing cholinergic neurons of varying density were: medial and lateral preoptic areas, septohypothalamic nucleus, median preoptic area, lateral hypothalamus including the perifornical area, anterior hypothalamic nucleus, arcuate nucleus, dorsomedial hypothalamic nucleus, posterior hypothalamic nucleus, dorsal and ventral premammillary nuclei, neuropil mediodorsal to the anterior hypothalamic nucleus, neuropil ventral to the anterior hypothalamic nucleus and ventromedial hypothalamic nucleus, neuropil between lateral hypothalamus and ventromedial hypothalamus, and neuropil between dorsal premammillary nucleus and posterior hypothalamic nucleus. There were also many varicose and non-varicose fibers in the preoptic area and hypothalamus. Two kinds of varicose fibers, one with strong immunoreactivity and the other with weak immunoreactivity, were seen. Non-varicose fibers were also detected in the optic chiasma and habenulo-interpeduncular tract. These fibers were passing fibers.

Animals↗
PubMed1987

Origin of cholinergic fibers in the basolateral nucleus of the amygdaloid complex by using sensitive double-labeling technique of retrograde biotinized tracer and immunocytochemistry.

Injection of biotin-wheat germ agglutinin into the basolateral nucleus of the amygdaloid complex of the rat labeled many neurons in the substantia innomionata, ventral pallidum, horizontal limb of the diagonal band, interstitial nucleus of the ansa lenticularis, and bed nucleus of the stria terminalis. Except for the labeled cells in the bed nucleus of the stria terminalis, simultaneous staining with antiserum against choline transferase (ChAT) showed that some of these neurons are ChAT-like immunoreactive. This highest density of the double-labeled cells was seen in the horizontal limb of the diagonal band and substantia innominata, less numerous in the ventral pallidum and a few double-labeled cells in the interstitial nucleus of the ansa lenticularis.

Acetylcholine↗
PubMed1987

Immunocytochemical localization of the choline acetyltransferase containing neuron system in the rat lower brain stem.

This distribution of choline acetyltransferase (CHAT) immunoreactivity (CHAT-I) in the rat lower brain stem was analyzed using a highly sensitive avidin-biotin immunocytochemical method and 3-amino-9-ethyl-carbazole visualization. A much wider and more abundant distribution of CHAT-I structures in the lower brain stem was demonstrated than in earlier studies. The following areas were newly identified as areas rich in CHAT-I fibers: the interpeduncular nucleus, medial geniculate body, central gray matter of pons, pontine nucleus, parabigeminal nucleus, dorsal tegmental nucleus of Gudden, lateral trapezoid nucleus, inferior colliculus, dorsal and ventral cochlear nuclei, medial and lateral vestibular nuclei, reticular formation of medulla oblongata, and gelatinosa of caudal trigeminal spinal tract nucleus. In addition to the areas in which they have been known to exist, CHAT-I perikarya were found in the caudal portion of substantia nigra pars reticulata, the area between trigeminal motor nucleus and superior olivary nucleus, the medial and spinal vestibular nucleus, prepositus hypoglossal nucleus, raphe magnus and obscurus, ventromedial portion of solitary tract nucleus and its just ventral reticular formation, and caudal trigeminal spinal tract nucleus.

Animals↗
PubMed1986

Distribution and origins of substance P (SP)-, calcitonin gene-related peptide (CGRP)-, vasoactive intestinal polypeptide (VIP)- and neuropeptide Y (NPY)-containing nerve fibers in the pineal gland of gerbils.

In the pineal gland of gerbils, substance P (SP)-, calcitonin gene-related peptide (CGRP)-, vasoactive intestinal polypeptide (VIP)- and neuropeptide Y (NPY)-containing nerve fibers were demonstrated immunohistochemically. After intrapineal injection of biotin-wheat germ agglutinin, origins of fibers were examined by the combined technique of tracing method and immunohistochemistry. It was confirmed that SP- and CGRP-fibers originated from the trigeminal ganglion, VIP-fibers from the pterygopalatine ganglion and NPY-fibers from the superior cervical ganglion.

Animals↗