Search PubMed⌕ Search

Biomedical subjects

A Konishi

Publications and source records attributed to A Konishi.

At least 73 records · Page 4Linked to original sources
PubMed1984

Cholinergic neurons in the nucleus tegmenti pedunculopontinus pars compacta and the caudoputamen of the rat: a light and electron microscopic immunohistochemical study using a monoclonal antibody to choline acetyltransferase.

Large neurons in the nucleus tegmenti pedunculopontinus pars compacta (TPC) of the rat were shown to have choline acetyltransferase (ChAT) immunoreactivity by light and electron microscopic immunohistochemistry using a monoclonal antibody to ChAT. The ChAT-positive TPC neurons had triangular or multipolar cell bodies with diameters of 20-50 micron. The ultrastructural features of the ChAT-positive TPC neurons were similar to those of ChAT-positive neurons in the caudoputamen; each neuron had a distinct, pale nucleus with an indented nuclear envelope and large, cytoplasm-containing, well-developed endoplasmic reticulum and pale mitochondria.

Animals↗
PubMed1984

Central distribution of afferent and efferent components of the pudendal nerve in cat.

Central distribution of afferent and efferent components of the pudendal nerve was examined in the cat by the HRP method after applying HRP to the central cut end of the pudendal nerve. Retrogradely labeled neuronal cell bodies were located primarily in the feline homologue of the Onuf's X nucleus, constituting a slender longitudinal cell column in the ventral horn of the S1 and S2 cord segments. The Onuf's nucleus was present constantly from middle S1 to high S2 cord segments, and occasionally extended rostrally to high S1 or low L7, and caudally to middle S2, low S2, or high S3 cord segments. No sex differences were observed in the distribution pattern, number, and soma size of labeled neurons in the Onuf's nucleus. Transganglionically labeled dorsal root fibers were found to terminate ipsilaterally in the lamina I of the dorsal horn at levels of lower lumbar, sacral, and higher coccygeal cord segments and the gracile nucleus, and bilaterally with an ipsilateral predominance in the dorsal commissural gray and laminae III, IV, V, and VI of the dorsal horn at levels of lower lumbar, sacral, and higher coccygeal cord segments. Some labeled dorsal root fibers appeared to end ipsilaterally in the regions where the sacral parasympathetic preganglionic neurons have been shown to be located.

Animals↗
PubMed1983

The posteromedial ventral nucleus of the thalamus (VPM) of the cat: direct ascending projections to the cytoarchitectonic subdivisions.

The posteromedial ventral nucleus (VPM) of the cat is divided cytoarchitectonically into the magnocellular (VPMmc), lateral parvocellular (VPMpcl), and medial parvocellular (VPMpcm) divisions. Cell bodies of neurons in the VPMpcm are small, while those in the VPMpcl are small to medium-sized. The VPMmc contains large neurons. Direct projections from the lower brain stem structures to each of the three divisions of the VPM were examined by the retrograde horseradish peroxidase (HRP) method. When HRP injection was done into the VPMmc, labeled neurons were mainly located contralaterally in the ventral division of the principal sensory trigeminal nucleus (Vp), in the rostral part of the oral subnucleus in the spinal trigeminal nucleus (Vsp), and in the interpolar subnucleus of the Vsp; a few labeled neurons were also found contralaterally in lamina I of the caudal subnucleus of the Vsp. When HRP injection was restricted to the VPMpcl or VPMpcm, HRP-labeled neurons were mainly observed ipsilaterally, respectively, in the dorsal division of the Vp, or in the parabrachial nucleus (PBN) regions dorsomedial and ventromedial to the brachium conjunctivum. After HRP injection into the parvocellular part of the VPM (VPMpc), labeled neurons were also seen contralaterally in the Vsp, but these were far less numerous than those seen after HRP injections into the VPMmc. Thus, each of the three divisions of the VPM receives main ascending afferent fibers from different brain stem structures; the VPMpcm, VPMpcl, or VPMmc receives afferent fibers, respectively, from the PBN ipsilaterally, from the dorsal division of Vp ipsilaterally, or from the ventral division of the Vp and the Vsp contralaterally.

Afferent Pathways↗
PubMed1983

A light and electron microscopic study of premotor neurons for the trigeminal motor nucleus.

Premotor neurons sending their axons to the trigeminal motor nucleus were observed in the cat by light and electron microscopy after labeling the neurons retrogradely or anterogradely with horseradish peroxidase (HRP). After HRP injection into the trigeminal motor nucleus, retrogradely labeled neurons were seen most frequently in the parvocellular reticular formation bilaterally. Many labeled neurons were also seen contralaterally in the intermediate zone at the rostralmost levels of the cervical cord and its rostral extension into the caudalmost levels of the medulla oblongata. Additionally, some neurons were labeled ipsilaterally in the mesencephalic trigeminal nucleus, contralaterally in the main sensory trigeminal nucleus and the trigeminal motor nucleus, and bilaterally in the oral and interpolar subnuclei of the spinal trigeminal nucleus. Only a few labeled neurons were seen in the confines of the gigantocellular reticular formation. All labeled neurons were small or of medium size; no large neurons were labeled. After HRP injection into the regions around the trigeminal motor nucleus or the parvocellular reticular formation, axodendritic terminals containing HRP granules were found contralaterally within the trigeminal motor nucleus. Some of these labeled terminals were filled with round synaptic vesicles and others contained pleomorphic synaptic vesicles. The varied morphology of labeled axon terminals was considered to reflect the functional heterogeneity of the premotor neurons for the trigeminal motor nucleus.

Animals↗
PubMed1982

Localization of motoneurons innervating the tensor tympani muscles: an horseradish peroxidase study in the guinea pig and cat.

Motoneurons innervating the tensor tympani muscle were identified in the adult guinea pig and cat by the horseradish peroxidase (HRP) method. After HRP injection into the tensor tympani muscle, HRP-labeled neurons were seen in the regions outside the cytoarchitectonically-defined confines of the trigeminal motor nucleus; in the regions rostral to the rostral pole of the nucleus, as well as in the regions ventral and ventrolateral to the nucleus at the levels of the rostral half (guinea pig) or the rostral two-thirds (cat) of the nucleus. The tensor tympani motoneurons were generally smaller than the masticatory motoneurons.

Animals↗
PubMed1982

Direct projections from the extrathalamic forebrain structures to the neocortex in the macaque monkey.

Extrathalamic direct projections from the subcortical forebrain structures to the neocortex were examined in the macaque monkey by the horseradish peroxidase method. The enzyme, when injected into discrete regions in the neocortex, labeled cell bodies of extrathalamic forebrain neurons in the basal nucleus of Meynert, nucleus of the diagonal band, medial septal nucleus, hypothalamus, claustrum and dorsolateral part of the basal amygdaloid nucleus. Neurons in the basal nucleus of Meynert, lateral hypothalamus and claustrum appeared to send their axons widely, but not diffusely, to the neocortex.

Animals↗
PubMed1981

Electron microscopic identification of axon terminals of retinopretectal fibers in the cat by a combined horseradish peroxidase and tritiated amino acids tracing method.

The terminal nucleus of the optic tract in the pretectum was observed electron microscopically in the cat after intravitreous injection of a mixture of HRP and tritriated amino acids. Autoradiographic silver grains, and often also HRP granules, were seen in large axon terminals containing round synaptic vesicles and pale mitochondria. These terminals occasionally made synaptic contracts with the presynaptic dendrites and were involved in the formation of the synaptic triad.

Animals↗
PubMed1981

Chronic hepatitis B: correlation between viral replication and clinical course.

Twenty carriers of hepatitis B virus (HBV) were followed for two to seven years, and their histologic progression was correlated with HBV core-associated DNA polymerase (DNAP) activity as a marker of viral replication. Seventeen patients were divided into two groups according to their pattern of viral replication: group 1, consistently high levels of DNAP; group 2, low levels of DNAP. Chronic persistent hepatitis predominated in group 1; chronic active hepatitis predominated in group 2. The three remaining patients were consistently negative for DNAP. In two patients in group 2, prominent viral replication preceded a transient increase in transaminase levels, as in acute hepatitis. Although groups 1 and 2 were distinct in their patterns of viral replication, they did not differ significantly in histologic progression. Thus, viral replication is related, at least in part, to hepatic cell necrosis but does not correlate closely with progression to liver cirrhosis.

Adult↗
PubMed1979

A cerebello-pulvino-cortical and a retino-pulvino-cortical pathways in the cat as revealed by the use of the anterograde and retrograde transport of horseradish peroxidase.

A cerebello-pulvino-cortical and a retino-pulvino-cortical pathways were revealed in the cat by means of the horseradish peroxidase (HRP) method. The sites of termination of the cerebellofugal and retinofugal fibers in the pulvinar nucleus (Pul) were visualized by the use of the anterograde transport of HRP. The cerebello-pulvinar fibers were found to arise mainly from the parvicellular region of the lateral cerebellar nucleus and to terminate contralaterally in a narrow area at the extreme dorsolateral edge of the Pul at the level of the stereotaxic frontal plane A-7.0. The area of terminal ramification of retino-pulvinar fibers was seen as a thin sheet lying at the extreme lateral edge of the Pul through most of the rostrocaudal extent of the Pul, bilaterally with contralateral predominance. The cerebellorecipient area in the Pul did not seem to overlap with the retinorecipient Pul area; the former appeared to be contiguous ventrolaterally to the latter. The cerebellorecipient and retinorecipient Pul areas were also observed to be connected reciprocally with the cerebral cortical areas; the former was connected with the most posterior part of the area 20, and the latter with the area 19.

Animals↗
PubMed1979

The site of origin of cardiac preganglionic fibers of the vagus nerve: an HRP study in the cat.

After injection of horseradish peroxidase (HRP) into the right cardiac branches of the vagus nerve in the cat, the majority of HRP-labeled neurons were located ipsilaterally in the reticular formation ventrolateral to the nucleus ambiguus. Additionally, HRP-labeled neurons were also observed within the nucleus ambiguus (Am) and the dorsal motor nucleus of the vagus nerve (DM).

Animals↗
PubMed1978

A quantitative electron microscope study of cerebellar axon terminals on the magnocellular red nucleus neurons in the cat.

In the red nucleus (RN) of the cat, the bouton covering ratio (BCR: the ratio of whole somatic surface length and that covered with axon terminals) and the density of axon terminals in contact with somatic profiles (DAST: the number of axosomatic terminals per micron of somatic surface membrane) were calculated in each neuronal somatic profile over 60 micron in diameter. The mean BCR was 61.4 +/- 1.43 (S.E. M.)%. The mean DAST of axosomatic terminals filled with spherical synaptic vesicles (S-terminals) was 27.7 +/- 0.95, and that of terminals with pleomorphic and/or flattened vesicles (F-terminals) was 10.3 +/- 1.12. Subsequently, sequential changes of the BCR and DAST of intact terminals were examined in the RN deafferented from the cerebellorubral fibers. The mean BCR and DAST were decreased most markedly during the survival period of 4-7 days; thus decrease was chiefly due to degeneration of S-terminals (BCR: 16.7 +/- 1.17 %, DAST of S-terminals: 7.1 +/- 1.12, DAST of F-terminals: 5.8 +/- 1.22). In the RN 11-63 days after the operation, both the BCR and DAST tended to re-increase slightly and the majority of the re-increased terminals appeared to be F-terminals. Possible meanings of this re-increase of axosomatic terminals are discussed.

Afferent Pathways↗