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S Inagaki

Publications and source records attributed to S Inagaki.

At least 163 records · Page 9Linked to original sources
PubMed1986

Atrial natriuretic polypeptide-like immunoreactivity in the rat pituitary: light and electron microscopic studies.

Immunoreactive atrial natriuretic polypeptide (ANP) was investigated in the pituitary of rats by light and electron microscopy using the indirect immunofluorescence and peroxidase-antiperoxidase techniques. ANP-like immunoreactivity was present in 30-35% of anterior pituitary cells. These cells have two types of secretory granules being characteristic of rat gonadotrophin-storing granules, and were usually adjacent to the capillary endothelium. The results of this study suggest the co-occurrence of ANP and gonadotrophins in the anterior pituitary cells.

Animals↗
PubMed1986

A substance P-containing pathway from the hypothalamic ventromedial nucleus to the medial preoptic area of the rat: an immunohistochemical analysis.

The destruction of the hypothalamic ventromedial nucleus, which contains a group of substance P-like immunoreactive neurons, resulted in a marked ipsilateral reduction of these fibers in the medial preoptic area. To test if and to what extent the substance P-like immunoreactive neurons in the ventromedial nucleus project to the medial preoptic area, we applied a sensitive double-labeling method capable of detecting substance P-like immunoreactivity in neurons retrogradely labeled with biotin-wheat germ agglutinin following injection of the tracer in the medial preoptic area. The appearance of many double-labeled cells in the hypothalamic ventromedial nucleus provides strong evidence for the existence of a prominent substance P containing pathway from the ventromedial nucleus to the medial preoptic area. A few doubled-labeled cells were also seen in the lateral hypothalamus, which therefore seems to be an additional source of substance P-like immunoreactive fibers in the medial preoptic area.

Animals↗
PubMed1986

Enkephalin-like immunoreactive neurons and fibers in the ventromedial hypothalamic nucleus.

Enkephalin-like immunoreactive (ENK-IR) neurons and fibers in the rat ventromedial hypothalamic nucleus (VMH) were examined by light and electron microscopy using the peroxidase-antiperoxidase immunocytochemistry. There were groups of ENK-IR neurons present in the ventrolateral part of the VMH, and such neurons were scattered elsewhere. These neurons had perikarya 10-25 microns in diameter with moderately developed cell organelles and enfolded nuclei that were often distributed eccentrically placed in the cell. The perikarya and dendrites contained diffuse, large-cored vesicles (LCV) (60-230 nm with a predominance in the 60-80 nm). ENK-IR neurons received synaptic inputs on the soma and dendrites from unlabeled axonal boutons containing many small, clear vesicles and occasional LCV. The ultrastructural features of the ENK-IR cells in the VMH seemed to correspond to the "common cells" described by Millhouse. Dense ENK-IR fibers were distributed in this nucleus throughout the rostrocaudal and ventrodorsal areas. Axonal boutons containing numerous small, clear vesicles, and dispersed LCV generally made synaptic contacts with the cell bodies and dendrites of unlabeled neurons. The findings suggest that opioid peptides directly influence VMH neurons through synaptic contacts.

Animals↗
PubMed1986

[Left ventricular function during atrial fibrillation assessed by left ventricular function curve using ECG-gated blood pool scintigraphy].

Cardiac function is difficult to assess in patients with atrial fibrillation due to the widely fluctuating cycle lengths resulting in variable ventricular hemodynamics. With respect to ECG-gated blood pool scintigraphy, distortion of the time activity curve occurs due to a summation of irregular cycle lengths. Therefore, performing such a study has been regarded meaningless. To evaluate left ventricular function during atrial fibrillation using scintigraphic technique, a new processing algorithm was devised to make multiple gated images which are discriminated by the preceding R-R interval, and left ventricular filling and function curves were established. The left ventricular filling curve, obtained by plotting end-diastolic volume against the preceding R-R intervals demonstrated an impairment of blood filling in cases of mitral stenosis and constrictive pericarditis, which resolved after mitral commissurotomy in case of mitral stenosis. The left ventricular function curve, established by plotting stroke volume against end-diastolic volume, was analyzed according to indices such as "slope" and "position". Both of these indices were significantly reduced in relation to the severity of heart failure according to the NYHA's functional classification and cardiomegaly on chest radiography. On individual comparisons of underlying diseases, the indices decreased in the following order; lone atrial fibrillation, hyperthyroidism, aging, hypertension, mitral valve disease, ischemic heart disease, dilated cardiomyopathy and aortic regurgitation. The indices correlated closely with ejection fraction. In cases of mitral regurgitation, however, the function curves were situated to the right and above those of lone atrial fibrillation and decreased in slope despite the fairly well-maintained ejection fraction. After treatment with digitalis and/or diuretics, the function curves shifted to the left and upward. In conclusion, left ventricular filling and function curves based on a newly-devised algorithm of ECG-gated blood pool scintigraphy are of considerable clinical value in evaluating cardiac performance in patients with atrial fibrillation. They are widely applicable to the assessment of therapeutic and interventional effects.

Atrial Fibrillation↗
PubMed1985

Distribution of enkephalin-immunoreactive neurons in the forebrain and upper brainstem of the squirrel monkey.

The distribution of enkephalin-immunoreactive neuronal profiles in the forebrain and upper brainstem of the squirrel monkey (Saimiri sciureus) was studied by means of the indirect immunofluorescence method. Numerous enkephalin-immunoreactive cell bodies and fibers were disclosed in various regions including cerebral cortex, hippocampus, caudate nucleus, putamen, nucleus accumbens, septal area, olfactory tubercle, substantia innominata, amygdala, various hypothalamic and thalamic nuclei, periaqueductal gray, midbrain reticular formation and interpeduncular nucleus. Some of the highest concentrations of enkephalin-positive fibers in the squirrel monkey brain were found in the external segment of the globus pallidus, the outer layer of the median eminence, and in the pars reticulata of the substantia nigra. Overall, the pattern of distribution of the enkephalin-immunoreactive cell bodies and fibers in the forebrain and upper brainstem of the squirrel monkey is similar to that found in the rat, except that the density of positive neuronal profiles in the entire forebrain appears much higher in monkey than in rat. Furthermore, the very dense network of enkephalin-immunoreactive fibers disclosed in the substantia nigra pars reticulata of monkey appears to be lacking in rat.

Amygdala↗
PubMed1985

An enkephalinergic projection from the hypothalamic paraventricular nucleus to the hypothalamic ventromedial nucleus of the rat: an experimental immunohistochemical study.

The distribution and origins of enkephalin-like immunoreactive (ENK-IR) fibers in the nucleus ventromedialis hypothalami (vm) of the rat were examined using immunohistochemistry. A dense plexus was evenly distributed in the vm with no regional differences. A group of ENK-IR neurons was concentrated in the ventrolateral portion of the vm. The destruction of the hypothalamic paraventricular nucleus (pv) which contained numerous ENK-IR neurons, resulted in a marked decrease in ENK-IR fibers in the vm on the operated side. In addition, the destruction of the magnocellular portion of the pv, while leaving most of parvocellular portion intact, failed to substantially decrease the ENK-IR fibers in the vm, suggesting that these fibers originate from ENK-IR neurons located in the parvocellular portion of the pv. The present study further showed that the axons of these neurons first proceeded laterally to the perifornical area, next ran ventrolaterally to the ventrolateral portion of the anterior hypothalamic nucleus and finally turned medially to the vm.

Animals↗
PubMed1985

Leucine-enkephalin-like immunoreactive fibers in the medial preoptic area of the rat: their distribution and origin.

We studied the distribution of fibers with leucine-enkephalin-like immunoreactivity (L-ENKI) in the medial preoptic area (MPO) of the rat, and the origins of such fibers, using indirect immunofluorescence and a combination of a retrograde tracer with immunocytochemistry that we have developed. These fibers were very dense throughout the rostro-caudal part of the MPO. The distribution was uneven with the highest density in the lateral part. Destruction of the arcuate nucleus, which contains a group of L-ENKI neurons, resulted in the marked reduction of these fibers in the ipsilateral MPO, suggesting that most of these fibers originate in this nucleus. This was also suggested by the fact that injection of biotin-wheat germ agglutinin into the MPO labelled many neurons in the arcuate nucleus ipsilaterally. Simultaneous staining with antiserum showed that some of these neurons are L-ENKI.

Animals↗
PubMed1984

Origins of histamine-containing fibers in the cerebral cortex of rats studied by immunohistochemistry with histidine decarboxylase as a marker and transection.

The origins of histamine-containing fibers in the cerebral cortex were examined by means of the retrograde tracer technique of horseradish peroxidase (HRP)-immunohistochemistry with histidine decarboxylase (HDC) as a marker for the histamine neuron system. Total transection of the brain rostral to the posterior hypothalamus resulted in disappearance of HDC-like immunoreactive (HDCI) fibers in the cerebral cortex, but total transection caudal to the posterior hypothalamus did not decrease the number of HDCI fibers in the cortex, suggesting that HDCI fibers in the cerebral cortex originate in the posterior hypothalamus. The projection of HDCI neurons from the posterior hypothalamus to the cerebral cortex seemed to be bilateral because hemi-transection of the brain rostral to the posterior hypothalamus resulted in a bilateral decrease of HDCI fibers in the cerebral cortex with ipsilateral predominance. After injection of HRP into the cerebral cortex, numerous cells containing both HRP granules and HDCI structures were found bilaterally in the tuberal, caudal and postmamillary magnocellular nuclei, with ipsilateral predominance. These findings indicate that HDCI cells in the above nuclei give rise to axons extending bilaterally to the cerebral cortex.

Animals↗
PubMed1984

Two distinct strio-nigral substance P pathways in the rat: an experimental immunohistochemical study.

Re-examination of the strio-nigral substance P (SP) tract by means of an experimental immunohistochemical method in the rats demonstrated the presence of two distinct pathways from the nucleus caudatus putamen (CP) to the substantia nigra (SN). Destruction of the posterior portion of the CP resulted in the disappearance of SP-positive fibers in the SN pars lateralis but not in the SN pars compacta or reticulata. On the other hand, destruction of the ventrolateral portion of the anterior portion of the CP caused the disappearance of SP-positive fibers in the SN pars compacta and pars reticulata but not in the SN pars lateralis. In addition, destruction of the dorsal portion of the anterior portion of the CP, where 3-6 cell islets of SP-positive cells are located, failed to decrease SP-positive fibers in any of the subdivisions of the SN. These findings strongly suggest that SP-positive neurons in the posterior portion of the CP project to the SN pars lateralis (posterior strio-nigral SP tract), SP-positive cells in the lateroventral part of the anterior portion of the CP extend to the SN pars compacta and pars reticulata, but SP-positive cells in the dorsal part of the anterior portion of the CP do not innervate the SN.

Animals↗
PubMed1984

Immunocytochemical localizations of cytosolic and mitochondrial glutamic oxaloacetic transaminase isozymes in rat brain.

The localizations of cytosolic (s-) and mitochondrial (m-) glutamic oxaloacetic transaminase (GOT) were examined by immunocytochemical methods using specific antibodies. Staining of s-GOT-like immunoreactivity was seen in periglomerular cells of the olfactory bulb, and basket, stellate cells of the cerebellum, and second layer cells of the neocortex. On the other hand, m-GOT-like immunoreactivity was found in mitral cells and glomerular regions of the olfactory bulb and deep Golgi cells of the cerebellum. These different distributions of s- and m-GOT isozymes suggest that these isozymes are available as markers of glutamergic or aspartergic neurons.

Animals↗
PubMed1984

The distribution and projection of gamma-melanocyte stimulating hormone in the rat brain: an immunohistochemical analysis.

The distribution and projection of immunoreactive gamma-melanocyte-stimulating hormone (gamma-MSHI) in the rat brain was examined by indirect immunofluorescence using an antiserum against synthetic rat gamma-MSH. The present study confirmed the presence of gamma-MSHI neurons in the arcuate nucleus and further demonstrated that the n. commissuralis is a new gamma-MSHI neurons-containing site. We also found a gamma-MSHI fiber network in the hypothalamus, thalamus, amygdala, central gray matter of the midbrain and upper pons, and further demonstrated a much more extensive distribution of these fibers particularly in the medulla oblongata, an area previously thought not to contain gamma-MSHI structures. The present observation on the normal distribution of gamma-MSHI suggested the existence of two different systems: one is the arcuatofugal gamma-MSH system and the other n. commissuralis gamma-MSH system. Using experimental manipulations, we clearly established that gamma-MSHI fibers in the forebrain, diencephalon, midbrain and upper pons originate from gamma-MSHI neurons in the arcuate nucleus and those in the medulla oblongata from the n. commissuralis .

Animals↗
PubMed1984

Experimental immunohistochemical studies on the substance P neuron system in the lateral habenular nucleus of the rat: distribution and origins.

We examined the distribution and afferent projections of substance P-like immunoreactive (SPI) fibers in the lateral habenular nucleus of the rats by using the indirect immunofluorescence method. On the basis of the distribution, a dense plexus of SPI fibers in the lateral habenular nucleus (LHb) could be divided into two parts: medial (mLHb) and lateral (lLHb). The present study demonstrates that SPI fibers in the lLHb originate from SPI cells in the rostral entopeduncular nucleus (rEP) and the adjacent area, while those in the mLHb originate from SPI cells in the medial habenular nucleus. Moreover, we showed that the axons from SPI cells in the rEP reached the lLHB via the "pallidohabenular tract."

Animals↗
PubMed1984

Ontogeny of neuropeptides in the nucleus ventromedialis hypothalami of the rat: an immunohistochemical analysis.

The ontogeny of leucine-enkephalin (ENK)-, cholecystokinin-8 (CCK)-, substance P (SP)- and neurotensin (NT)-like immunoreactive structures were examined in the nucleus ventromedialis hypothalami (vm) of the rat by means of an indirect immunofluorescence method. ENK- (ENKI), SP- (SPI) and CCK-like immunoreactive (CCKI) structures in the vm exhibited very similar ontogenetic developments, though no CCKI cells were detected. ENKI fibers as well as SPI fibers and neurons first appeared at gestational day 21, ENKI neurons at postnatal day 2, and CCKI fibers at postnatal day 1. These structures subsequently increased in number. The maximum content was reached at postnatal day 21 and was observed even in the adult rats (postnatal day 30). On the other hand, NTI fibers first appeared at postnatal day 1; they decreased in number and no or only a few NTI fibers were seen in the adult rats. No NTI cells were seen in the vm.

Animals↗