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Y Ibata

Publications and source records attributed to Y Ibata.

At least 163 records · Page 9Linked to original sources
PubMed1984

The fine structures of the VIP-like immunoreactive neurons in the cat hypothalamus.

The fine structures of the VIP-like immunoreactive neurons in the suprachiasmatic nucleus (SCN) and the arcuate nucleus ( ARN ) of the cat hypothalamus were investigated by electron microscopic immunocytochemistry. The VIP-like immunoreactive soma and fibers could be successfully visualized by a modified PAP method. VIP-like immunoreactive neurons in both nuclei contained immunoreactive rER, Golgi complexes and many immunoreactive granules, as well as well developed mitochondria. VIP-like immunoreactive synaptic endings with synaptic membrane specialization of Gray's type I and II were found in the SCN. Moreover VIP-like immunoreactive preterminal elements that made synaptic contact with VIP-like immunoreactive neuronal soma were also detected. On the other hand, it was difficult to detect typical preterminal endings with immunoreactivity in the ARN ; however, VIP-like immunoreactive processes in contact with the basement membrane of the capillaries were observed. These observations indicate that VIP-like immunoreactive neurons in the SCN act as intrinsic neurons and are involved in neuroendocrine function in ARN .

Animals↗
PubMed1984

New application of catecholamine fluorescence histochemistry using glyoxylic acid for diagnosis of Hirschsprung's disease by rectal biopsy.

Catecholaminergic innervation was studied in the rectal biopsy specimen obtained from patients with Hirschsprung's disease. The histofluorescence of catecholamine was examined using glyoxylic acid and magnesium without freeze-drying. Aganglionic specimens exhibited no fluorescent network of terminals or fibres in the submucosal plexus, whereas ganglionic specimens showed ganglion cells surrounded by a network of catecholaminergic terminals and fibres. These results of rectal biopsy could be obtained easily and quickly with good reliability. Examination of the catecholaminergic innervation by this histofluorescence method provides a new approach to the diagnosis of Hirschsprung's disease.

Adrenergic Fibers↗
PubMed1983

Hypothalamo-retinal centrifugal projection in the dog.

Horseradish peroxidase (HRP)-filled neurons and their processes were consistently detected in the ventral portion of the dog hypothalamus after intraocular injection of HRP. The number of HRP-filled neurons decreased in parallel with the extent of the resection of the optic nerve. HRP-filled neurons were never detected in specimens with a complete resection of the optic nerve. These findings strongly indicate that these HRP-filled neurons in the ventral hypothalamus are the source of centrifugal fibers to the retina.

Animals↗
PubMed1983

Coexistence of dopamine and neurotensin in hypothalamic arcuate and periventricular neurons.

The coexistence of dopamine and neurotensin in the same neuronal perikarya in the arcuate nucleus of the rat hypothalamus was examined by combined fluorescence histochemistry and immunohistochemistry on the same tissue sections and we obtained the evidence of the coexistence of two substances. The functional significance of those two substances for the prolactin release from the anterior pituitary was also briefly discussed.

Animals↗
PubMed1983

Some cellular characteristics of somatostatin neurons and terminals in the periventricular nucleus of the rat hypothalamus and median eminence. Electron microscopic immunohistochemistry.

Somatostatin neuronal perikarya and their processes, presumably dendrites, in the periventricular nucleus of the rat hypothalamus and terminals in the median eminence were observed by electron microscopic immunohistochemistry. Neuronal perikarya and processes contained immunoreactive dense granules (100-120 nm in diameter) and other cellular components such as polysomes, rER membranes occasionally showed high electron density. Few axo-somatic terminals were found on the somatostatin neurons, but we could detect a number of preterminal axons on immunoreactive processes, presumably dendrites. Therefore, we considered that somatostatin neurons receive mainly neuronal input through axo-dendritic synapses rather than through axo-somatic ones. In the somatostatin terminals in the external layer of the median eminence immunoreactivity was completely restricted on the granules.

Animals↗
PubMed1983

A whole-mount horseradish peroxidase study of the retinal central projection in normal and monocular rats.

Anatomical mapping of the retinal central projection in albino rats was performed by whole-mount HRP histochemistry, after intraocular injection of HRP. The overall features of the retinal central pathways from the optic chiasma to the superior colliculus as well as the accessory optic systems in normal and monocular rats were clearly visualized, following application of a modified tetramethyl benzidine method on the whole-mounted brain stems including the diencephalon and the mid-brain. When combined with a partial retinal lesion, the whole-mount HRP method made feasible detection of the spatial retinotopy of the collicular projection.

Animals↗
PubMed1983

VIP (vasoactive intestinal polypeptide)-like immunoreactive amacrine cells in the retina of the rat.

Vasoactive intestinal polypeptide (VIP)-like immunoreactivity was demonstrated in the rat retina, using the peroxidase anti-peroxidase (PAP) method. VIP-like immunoreactivity was observed in the cytoplasm of amacrine cells of the inner nuclear layer (INL) and their varicose processes ramifying in the inner plexiform layer (IPL). VIP-like immunoreactive amacrine cells were present in both central and peripheral retinal regions. In some sections fine ramifications of varicose processes in the IPL could be clearly traced. VIP-like immunoreactivity was detected in both 'stratified' and 'diffuse' amacrine cells. VIP-like immunoreactive amacrine cells were classified into four types.

Animals↗
PubMed1983

Time of vasopressin neuron origin in the mouse hypothalamus: examination by combined technique of immunocytochemistry and [3H]thymidine autoradiography.

A time-course study on production of vasopressin neurons (VP-neurons) in the mouse hypothalamus was carried out by application of [3H]thymidine autoradiography and PAP-immunocytochemistry simultaneously on the same tissue sections. In the paraventricular nucleus (PVN) and the supraoptic nucleus (SON), heavily [3H]thymidine-labeled VP-neurons were detected only in the specimens of the animals exposed to the isotope on the gestational day 12. While in the suprachiasmatic nucleus (SCN), heavily isotope-labeled VP-neurons were observed in the specimens of the animals exposed to the isotope on the gestational day 12 or day 14. Therefore, the production of the VP-neurons in the SCN is prolonged and slightly more delayed than that in the SON or PVN.

Animals↗
PubMed1983

Distribution of the VIP-like immunoreactive neurons in the cat central nervous system.

Immunohistochemical topographic localization of the vasoactive intestinal polypeptide (VIP)-like immunoreactive neurons in the cat brain was investigated using a peroxidase anti-peroxidase technique. VIP-like immunoreactive neurons were mainly localized in the cerebral cortex, limbic cortex, hypothalamic nuclei; suprachiasmatic nucleus, supraoptic nucleus, paraventricular nucleus, periventricular nucleus and arcuate nucleus, and in the midbrain; such as the central grey and the raphe nucleus. It was demonstrated that VIP-like immunoreactive neurons were widely distributed in the cat brain, particularly in the hypothalamus, compared with those of the rat and mouse; though whether these differences were species-related or due to differences in the physiological conditions remains to be determined. This is the first report of VIP neuronal perikarya in the arcuate nucleus of mammalian species, although these cells are present in the arcuate nucleus of birds.

Animals↗
PubMed1982

An immunohistochemical investigation of vasoactive intestinal polypeptide in the colon of patients with Hirschsprung's disease.

The distribution of vasoactive intestinal polypeptide (VIP) in the colon of patients with Hirschsprung's disease was investigated by the peroxidase-antiperoxidase (PAP) immunohistochemical method. Three colonic segments, ganglionic, oligoganglionic and aganglionic, were stained by the unlabeled antibody enzyme method. VIP immunoreactive nerve cell bodies, nerve fibers and nerve endings were distributed throughout the ganglionic and oligoganglionic segments. In contrast, the aganglionic segment contained no VIP nerve endings and the number of fibers was reduced. These differences are thought to be a cause of constriction of the colon in Hirschsprung's disease and VIP neurons are therefore believed to participate in the relaxation of smooth muscle.

Child↗
PubMed1982

Postnatal development of vasoactive intestinal polypeptide immunoreactive amacrine cells in the rat retina.

The ontogenic development of vasoactive intestinal polypeptide (VIP)-immunoreactive amacrine cells in the rat retina was studied using peroxidase-antiperoxidase (PAP) immunohistochemistry. In the rat retina, VIP immunoreactivity appeared entirely in postnatal stage. On the 12th postnatal day, VIP-immunoreactive amacrine cells could be first detected. However, VIP immunoreactivity was very weak and VIP-immunoreactive amacrine cell processes could not be observed at this stage. On the 21st postnatal day, VIP-immunoreactive amacrine cell bodies became more mature and their processes were distinctly observed, resembling their appearance in adult rat retinas. VIP immunoreactivity could be detected in both stratified and diffuse amacrine cells at this stage. The relationship between the first appearance of VIP-immunoreactive amacrine cells and the synaptic formation in the inner plexiform layer is briefly discussed.

Animals↗
PubMed1982

Morphological studies on neuroglia. IV. Proliferative response of non-neuronal elements in the hippocampus of the rat to kainic acid-induced lesions.

Autoradiographic studies showed that in the rat hippocampus "microglia-like reactive cells" (MRS) and astrocytes are capable of proliferation in response to kainic acid (KA)-induced lesions. A marked increase in the number of labeled MRC was observed during the first four days after the induction of the KA-lesion. A proliferative response of astrocytes occurred at two days after the KA-lesion. After the induction of a KA-lesion brain macrophages and oligodendrocytes were only slightly labeled with 3H-thymidine. It appears likely that MRC is the main cellular element responding to this type of lesion.

Animals↗
PubMed1982

The localization of the motor neurons innervating the cricothyroid muscle in the adult dog by the fluorescent retrograde axonal labeling technique.

Injection of 4'6-diamidino-2-phenylindol 2 HCl (DAPI) into the cricothyroid muscle of the adult dog resulted in blue fluorescence of cells found exclusively in the rostral part of the ipsilateral nucleus ambiguus. These labeled neurons on the average extended 1.8 mm from the level just caudal the facial nucleus to the caudal extension. In the rostral tip of the nucleus, labeled cells were located in a scattered ventral group of larger neurons of the nucleus.

Animals↗
PubMed1982

Effects of heating on electrical activities of guinea pig olfactory cortical slices.

We examined the effect of heating on electrical activity of neurons in the guinea pig olfactory cortex slice. At the control temperature (37 degree C) the potential evoked by stimulation of the lateral olfactory tract consisted of an initial spike (IS) potential and a negative (N) potential. The IS potential is considered to be presynaptic and the other transsynaptic. The IS potential decreased in amplitude on heating and completely disappeared at 49 degree C. However, it recovered when the temperature was lowered to 37 degree C after five minutes of incubation at 49 degree C. In contrast, the N potential increased in amplitude at 39 degree C, was completely suppressed at 47 degree C and did not recover when the temperature was dropped to the control temperature. The maximum temperature from which the N potential recovered was 43 degree C. Unit activity was extracellularly recorded from neurons in the slice. On heating the brain slice some neurons showed an increase in activity others a decrease, and the rest were unaffected. We conclude that neurons in the olfactory cortex have different thermal sensitivities.

Animals↗
PubMed1981

Retinotopic analysis of fiber pathways is amphibians. I. The adult newt Cynops pyrrhogaster.

The possibility that pathways of retinal fibers within the optic tract and the tectum of the adult newt are retinotopic was examined by selective labeling of the retinal fibers with horseradish peroxidase. Within the optic tract fibers from the ventral, temporal and dorsal retinal quadrants were ordered from the dorsal to ventral edges of th optic tract. The nasal retinal fibers exhibited two different pathways. The fibers from the dorsonasal retina ran along the ventral edge of the optic tract, while the fibers from the ventronasal retina ran along the dorsal edge of the optic tract. Segregation of pathways within the optic tract was incomplete between the nasal and other retinal fibers. The dorsonasal retinal fibers were mixed completely with the dorsal retinal fibers, and the ventronasal retinal fibers were mixed partly with the ventral retinal fibers. Both the dorsal and dorsonasal retinal fibers preferentially entered the lateral tract, and finally projected onto the ventrolateral parts of the middle tectum and of the caudal tectum, respectively. The ventral and ventronasal retinal fibers entered the dorsomedial tract, and projected onto the dorsomedial parts of the middle tectum and of the caudal tectum, respectively. The temporal retinal fibers invaded the nasal tectum directly. Most dorsal, ventral, and nasal retinal fibers ran along the sub-tracts as far as to the level of their terminals, then sharply turned in a direction to the tectum.

Afferent Pathways↗
PubMed1981

Retinotopic analysis of fiber pathways in amphibians. II. The frog Rana nigromaculata.

The possibility of retinotopic organization of pathways of retinal fibers within the optic tract and the tectum of the frog was studied by selective labeling of the retinal fibers with horseradish peroxidase. Within the optic tract the pathways of the ventral, temporal and dorsal retinal fibers were ordered from the dorsal to ventral edges of the optic tract. The nasal retinal fibers ran along both the dorsal and ventral edges of the optic tract. The dorsal retinal fibers and the nasal retinal fibers which were located along the ventral edge of the optic tract entered the ventrolateral perimeter of the tectum and formed the lateral tract. The ventral retinal fibers and the nasal retinal fibers which were located along the dorsal edge of the optic tract entered the dorsomedial perimeter of the tectum and formed the dorsomedial tract. The temporal retinal fibers invaded the tectum directly at the diencephalo-tectal junction. The topography of fiber pathway observed for the frog was exactly the same as that seen in the newt, and seemed to be common to all amphibian species.

Afferent Pathways↗