Biomedical subjects

H Kiyama

Publications and source records attributed to H Kiyama.

At least 19 recordsLinked to original sources

PubMed1992

Regional distribution of cells expressing glycine receptor alpha 2 subunit mRNA in the rat brain.

The alpha 2 subunit of the glycine receptor is expressed transiently in the rat brain during early development suggesting that this subunit may be replaced by the alpha 1 subunit in the adult brain. The expression of glycine receptor alpha 2 subunit mRNA was investigated in the 7-day-old rat brain by in situ hybridization histochemistry using oligonucleotide probes specific for this subunit. Neurons expressing alpha 2 subunit mRNA were found to be widely and abundantly distributed throughout brain. We compared the distribution of neurons expressing alpha 2 subunit mRNA with that of neurons expressing alpha 1 or beta subunit mRNA. In the lower brainstem, the location of the neurons expressing alpha 2 subunit mRNA was very similar to that of the neurons with alpha 1 or beta subunit mRNA. Neurons expressing beta subunit mRNA were widespread and numerous in the forebrain, where neurons with alpha 1 subunit mRNA were uncommon. The locations of the neurons labeled by the alpha 2 probe were very similar to those of the cells labeled by the beta probe. These findings suggest that the alpha 2 subunit is not only expressed by immature neurons containing the alpha 1 subunit, but is also common to most immature neurons having the glycine receptor. However, it should be noted that several neurons contained beta and/or alpha 1 subunit mRNA but lacked alpha 2 subunit mRNA, suggesting that the glycine receptor is heterogeneous in its composition during brain development.

Animals↗

PubMed1992

c-fos may code for a common transcription factor within the hypothalamic neural circuits involved in osmoregulation.

Conscious rats were given an intraperitoneal (i.p.) injection of isotonic or hypertonic saline, and killed 10-240 min later. In the hypothalamus of hypertonic saline-injected rats, c-fos-mRNA positive cells were mainly restricted to the supraoptic and paraventricular nuclei and to structures associated with the lamina terminalis of the third ventricle, including in particular the subfornical organ, the organum vasculosum of the lamina terminalis (OVLT) and the median preoptic nucleus. These structures comprise the proposed anterior hypothalamic 'osmoreceptor complex' for regulation of vasopressin release. The time course of the appearance and disappearance of c-fos mRNA signals was similar in all regions. Thus c-fos protein (Fos) may be a common transcription factor in the hypothalamic neural circuits involved in osmoregulation.

Animals↗

PubMed1992

Postnatal development of mRNA specific for a metabotropic glutamate receptor in the rat brain.

We examined the ontogenesis of a subtype of metabotropic glutamate receptors, termed mGluR1, which is linked to phosphoinositide metabolism, in various regions of rat brain during neonatal development. Northern blot analyses of mGluR1 mRNA indicated that mRNA increased monotonously or remained at plateau levels during the first 5 weeks after birth. In situ hybridization analyses supported this conclusion. The result is in contrast with the reported development of the activity in excitatory amino acid-stimulated phosphoinositide turnover during the same period. The latter increases during the first few weeks and then decreases sharply.

Animals↗

PubMed1992

The GABAA receptor gamma 1 subunit is expressed by distinct neuronal populations.

The distribution of GABAA receptor gamma 1 subunit was examined in the rat central nervous system using in situ hybridization histochemistry. The gamma 1 subunit was expressed in relatively limited areas compared to other subunits investigated previously. The brain regions strongly expressing this subunit were the septum, globus pallidus, bed nucleus of the stria terminalis, hypothalamic periventricular nucleus, supraoptic nucleus, medial and central nuclei of the amygdaloid complex, medial part of the medial geniculate body, substantia nigra pars reticulata, interpeduncular nucleus, lateral parabrachial nucleus, Purkinje cell layer of the cerebellum, and inferior olivary nucleus. This relatively limited expression implies a possible role of gamma 1 subunit in relation to some specific neuronal circuit.

Animals↗

PubMed1992

Localization of GABAA-receptor gamma 2-subunit mRNA-containing neurons in the rat central nervous system.

The localization of neurons containing mRNA of the gamma 2-subunit of GABAA receptors was examined in the rat central nervous system with in situ hybridization histochemistry using an oligonucleotide probe to the sequence of the gamma 2-subunit. Neurons containing the gamma 2-subunit mRNA were widely but unevenly distributed in the brain. The location of gamma 2-subunit mRNA-containing neurons differed from those containing alpha- or beta-subunits. According to our results brain regions can be divided into three categories: one containing only gamma 2-subunit, one containing mRNA of at least one subunit other than gamma 2 and one containing more than one other subunit but not the gamma 2-subunit. The distribution of strongly labeled nuclei partly coincided with that of glutamate decarboxylase, suggesting that the GABAA receptor gamma 2-subunit would be involved in an autoreceptive mechanism of the GABAergic transmission.

Animals↗

PubMed1992

GABAA receptor subunit messenger RNAs show differential expression during cortical development in the rat brain.

Developmental changes of the expression of various GABAA receptor subunits (alpha 1, alpha 3, alpha 4, beta 1-3, and gamma 2) were examined in the fetal rat cerebral cortex using in situ hybridization histochemistry. The subunits showed three main patterns of development. The alpha 1 subunit showed the first pattern, in which no expression was observed during embryonic development. The alpha 4 and beta 1 subunits showed the second pattern, in which expression was observed in both the undifferentiated neuroepithelium and the developing cortical layers. The alpha 3, beta 2, beta 3, and gamma 2 subunits showed the third pattern, in which expression was only seen in the developing cortical layers. These findings strongly suggest the following: (i) the alpha 1 subunit is involved in GABAergic transmission in the mature cerebral cortex; (ii) the alpha 4 and beta 1 subunits are involved in both the differentiation of the neuroepithelium and the development of the cortical plate, and (iii) the alpha 3, beta 2, beta 3, and gamma 2 subunits are involved in the development of the cortical plate. Subunits already expressed on embryonic day 13 (beta 1, beta 3, and gamma 2) appear especially likely to have a special role in neuronal development.

Animals↗

PubMed1992

Different postnatal development of cells expressing mRNA encoding neurotensin receptor.

In situ hybridization histochemistry revealed three different ontogenetic patterns of localized expression of the high-affinity type of neurotensin receptor mRNA in the developing rat brain: one comprises sites which showed transient expression of neurotensin receptor mRNA during the first postnatal week, the expression greatly decreasing thereafter (type I); another comprises sites at which there is a gradual increase in neurotensin receptor mRNA after birth, as there is in cell number and intensity, with advancing age, followed by a plateau (type II); the third comprises sites at which there is much expression of neurotensin receptor mRNA already at birth, and a slight decrease thereafter (type III). The cerebral cortex, except retrosplenial and entorhinal cortices, and the anterior dorsal thalamic nucleus exhibit the type I pattern, while the horizontal and vertical limbs of the diagonal band of Broca, magnocellular preoptic nucleus, substantia innominata, ventral part of the suprachiasmatic nucleus, medial habenular nucleus, ventral tegmental area and substantia nigra pars compacta exhibit the type II pattern. The tenia tecta, retrosplenial and entorhinal cortices exhibit the type III pattern. One of the most striking findings in this study was that the entire neocortex and most of the limbic cortex exhibit the type I pattern, i.e. neurotensin receptor mRNA is expressed transiently long before a neuronal network is established there. This suggests that neurotensin plays an important role in cortical development, other than its reported transmitter-like role in the adult.

Aging↗

PubMed1991

Postnatal ontogeny of cells expressing prepro-neurotensin/neuromedin N mRNA in the rat forebrain and midbrain: a hybridization histochemical study involving isotope-labeled and enzyme-labeled probes.

The postnatal ontogeny of cells expressing prepro-neurotensin/neuromedin N messenger RNA (prepro-NT/NN mRNA) in the rat forebrain and midbrain was investigated by in situ hybridization histochemistry. According to the pattern of expression during development, the cells which express prepro-NT/NN mRNA can be roughly divided into 2 groups. In type I cells, prepro-NT/NN mRNA expression reaches a maximum in terms of content during the postnatal period. After this early peak, cells of this type express the same or less prepro-NT/NN mRNA, reaching a plateau at an adult level that still contains a high level of expression. In type II cells, prepro-NT/NN mRNA appears during the postnatal period, and the expression decreases dramatically after the first postnatal week, being almost undetectable by a few weeks after birth. Type I cells were observed in the following areas: the piriform cortex, field CA1 of Ammon's horn, subiculum, vertical, and horizontal limbs of the diagonal band of Broca, intermediate part of the lateral septal nucleus, bed nucleus of the stria terminalis, medial preoptic area, lateral hypothalamus, caudal part of the caudate putamen, medial, cortical, and central amygdaloid nuclei, ventral tegmental area, deep mesencephalic nucleus, cuneiform nucleus, dorsal raphe nucleus, laterodorsal tegmental nucleus, parabrachial nucleus, and oral part of the pontine reticular nucleus. Cells of type II were observed in the following areas: the mitral cell layer of the olfactory bulb, rostral part of the caudate putamen, (anterior) cingulate cortex, and retrosplenial cortex (posterior cingulate cortex).

Aging↗

PubMed1991

Transient expression of neurotensin mRNA in the mitral cells of rat olfactory bulb during development.

The transient expression of neurotensin mRNA in the mitral cells of the rat olfactory bulb was demonstrated during the perinatal period using non-radioactive in situ hybridization in which an alkaline phosphatase labelled oligodeoxynucleotide probe was used. The relative cellular content of neurotensin mRNA signal was measured by use of a microdensitometer. Neurotensin mRNA positive cells were observed in the primordium of mitral cells on embryonic day 14 and their mRNA content increased gradually up to the day of birth. During the first postnatal week, the strength of their neurotensin mRNA signal decreased dramatically, and continued to decrease until in the adult olfactory bulb neurotensin mRNA was no longer detectable. This decrease of the neurotensin mRNA content coincided with a parallel decrease of neurotensin immunoreactivity observed in the lateral olfactory tract.

Animals↗

PubMed1991

The transient appearance of proneurotensin mRNA in the rat hypoglossal nucleus during development.

Using a sensitive non-radioactive in situ hybridization technique utilizing alkaline phosphatase labelled oligodeoxynucleotide neurotensin probe we have observed the transient expression of neurotensin mRNA in the rat hypoglossal nucleus. Neurotensin mRNA containing cells were first observed on embryonic day 14 in the primodium of the hypoglossal nucleus. The intensity of the mRNA signal increased during the perinatal period until a maximum signal was observed at birth. After this time, the intensity of the neurotensin mRNA signal decreased dramatically during the first postnatal week. Subsequently the mRNA signal decreased gradually during maturation until only a very weak signal was detected in the adult. The visualization of neurotensin mRNA containing cells in the hypoglossal nucleus has not previously been reported. The transient expression of NT mRNA containing cells prior to birth may suggest that neurotensin has a role in the development of this nucleus.

Aging↗

PubMed1991

Differential effects of acute dopaminergic D1 and D2 receptor antagonists on proneurotensin mRNA expression in rat striatum.

The effect of acute dopamine (DA) antagonist treatment on neuronal proneurotensin (NT) mRNA was investigated in the rat striatum using a technique of non-radioactive in situ hybridisation. Adult Wistar rats were given a single intraperitoneal injection of either raclopride (D2 antagonist), SCH 23390 (D1 antagonist) or its inactive isomer SCH 23388 and left to survive for 3 h. Their brains were rapidly removed and striatal sections processed for in situ hybridisation using an alkaline phosphatase (AP) labelled oligonucleotide specific for NT mRNA. Blockade of the DA D2 receptors by a single injection of raclopride resulted in an increase in the number of NT mRNA containing cells in the dorsal lateral rim of the striatum adjacent to the corpus callosum. In contrast, no such increase was observed following blockade of the DA D1 receptors with SCH 23390. These findings demonstrate that NT mRNA expression is differentially regulated in the adult rat striatum by selective D1 and D2 antagonists.

Animals↗

PubMed1991

Colchicine-induced expression of proneurotensin mRNA in rat striatum and hypothalamus.

The effect of colchicine treatment on proneurotensin mRNA expression was examined using a sensitive non-radioactive in situ hybridization histochemistry technique with an enzyme-labelled antisense oligonucleotide probe. Intraventricular injection of colchicine rapidly induced strong neurotensin mRNA expression in a number of neurons in the dorsomedial part of the caudate putamen, and in the paraventricular, and arcuate nuclei while an induction of neurotensin mRNA was not observed in vehicle (saline)-injected animals. Neurotensin mRNA was not induced significantly in other periventricular areas such as the medial preoptic area or the lateral septum. These results indicate that colchicine can itself rapidly induce neurotensin mRNA expression and that this induction is specific to certain cell populations in the vicinity of the ventricles. These results demonstrate that colchicine should be used with caution in immunohistochemical studies demonstrating the normal distribution of peptide immunoreactivity or mRNA.

Animals↗

PubMed1991

Co-expression of cholecystokinin mRNA and tyrosine hydroxylase mRNA in populations of rat substantia nigra cells; a study using a combined radioactive and non-radioactive in situ hybridization procedure.

Improvements in the sensitivity of non-radioactive in situ hybridization histochemistry methods for detection of mRNA now make it feasible to combine the use of non-radioactive and radioactive in situ methods to visualize two mRNAs on the same tissue section. The method reported here allows the simultaneous detection of two mRNAs in one cell and therefore is ideally suited to the studies of co-expression. Here we demonstrate the co-expression of tyrosine hydroxylase (TH) mRNA and cholecystokinin (CCK) mRNA in the ventral mesencephalic dopaminergic neurones of the rat. The distribution of dopaminergic neurones containing both TH and CCK transcripts suggests, on the basis of earlier anatomical studies that these CCK/TH-containing doubled-labelled cells project mainly to the striatal matrix. Dopamine neurones believed to project to the patch compartment did not contain CCK mRNA.

Animals↗

PubMed1991

Dopaminergic D1 and D2 receptor antagonists decrease prosomatostatin mRNA expression in rat striatum.

The effect of acute dopamine receptor antagonist treatment on cellular prosomatostatin mRNA expression was investigated in the adult rat striatum using the technique of non-radioactive in situ hybridization. Adult female Wistar rats were given a single intraperitoneal injection of either raclopride (D2 antagonist), SCH 23390 (D1 antagonist) or the D1 (S) enantiomer SCH 23388. Animals were killed either 1, 3 or 9 h following the single i.p. injection and their brains rapidly removed. Striatal sections were then processed for in situ hybridization using an alkaline phosphatase-labelled oligonucleotide probe complementary to a portion of the rat somatostatin cDNA. Blockade of dopamine D1 and D2 receptors resulted in a significant decrease in the cellular content of prosomatostatin mRNA. However, no change in the number of prosomatostatin mRNA containing striatal cells was observed following any of the treatments at any time point. These findings demonstrate that the cellular content of prosomatostatin mRNA in the adult rat striatum is influenced by selective dopamine D1 and D2 receptor antagonists. Further, these findings are consistent with a functional interaction between dopamine and somatostatin in the rat striatum.

Animals↗

PubMed1991

Developmental control over vitamin-D-induced calbindin gene expression during early differentiation of chicken jejunal enterocytes.

In situ hybridization and immunocytochemical techniques have been used to examine the distribution of vitamin-D-induced calbindin mRNA and calbindin protein in enterocytes lining the crypts and villi of chicken small intestine. Basal villus enterocytes contained approximately twice as much calbindin but over three times as much calbindin mRNA compared to values found in basal crypt and upper villus enterocytes, all values being measured 2 days after vitamin D injection into D-deficient chickens. Virtually no calbindin mRNA was detected in tissues taken from control D-deficient birds. Direct proportionality found between calbindin mRNA and calbindin content in enterocytes of basal crypt, mid and upper villus suggests pre-translational control over calbindin synthesis. The implications of possible inefficient translation of calbindin mRNA in basal villus enterocytes are discussed. Present methods of analysis provide a novel way to study mechanisms controlling gene expression throughout the whole process of enterocyte differentiation.

Animals↗

PubMed1991

Electrical activation and c-fos mRNA expression in rat neurosecretory neurones after systemic administration of cholecystokinin.

1. The expression of c-fos mRNA in the rat hypothalamus was examined by in situ hybridization following systemic administration of cholecystokinin (CCK), a procedure known to activate magnocellular oxytocin neurons but not magnocellular vasopressin neurones. 2. Conscious male rats were given a single I.P. injection of 50 micrograms/kg CCK, c-fos mRNA signal was apparent in the supraoptic and paraventricular nuclei in rats killed 10 min after injection but not in uninjected or saline-(vehicle) injected rats. The density of c-fos mRNA at both sites was further elevated in rats killed 30 min or 60 min following injection, and was absent in rats killed 4 h after injection. 3. In the paraventricular nucleus the most dense expression of c-fos mRNA following CCK administration was in the medial, mainly parvocellular portion of the nucleus, in an area corresponding to the distribution of corticotrophin-releasing factor mRNA determined by in situ hybridization in adjacent sections. 4. The I.P. injection of CCK increased plasma oxytocin concentrations, measured by specific radioimmunoassay from 13 +/- 5 pg/ml in control rats to 107 +/- 9 pg/ml in the rats killed 10 min after injection, a similar response to that observed previously in urethane-anaesthetized rats. 5. In each of six urethane-anaesthetized rats, recordings were made from single neurones in the supraoptic nucleus, identified antidronomically as projecting to the posterior pituitary and identified electrophysiologically as putative oxytocin neurones. Following I.P. injection of 50 micrograms/kg CCK, the neurones increased their firing rate by a mean of 1.3 +/- 0.2 spikes/s averaged over the 10 min following injection. 6. From the appearance of c-fos mRNA in supraoptic neurones following CCK administration we conclude that this message is expressed in magnocellular oxytocin neurones, since vasopressin neuronal activity and vasopressin release is known to be unaffected by this stimulus, and since the supraoptic nucleus contains essentially only oxytocin neurones and vasopressin neurones. 7. We conclude that c-fos mRNA expression can be induced in supraoptic oxytocin neurones following brief and modest episodes of electrical activation, suggesting that c-fos may be involved in the gene regulation of these neurones under physiological conditions.

Action Potentials↗

PubMed1991

An in situ hybridization histochemistry method for the use of alkaline phosphatase-labeled oligonucleotide probes in small intestine.

We have developed a method of non-radioactive in situ hybridization histochemistry using alkaline phosphatase-labeled oligonucleotide probes to detect gene expression in the intestine. Because the intestine contains a large amount of endogenous alkaline phosphatase activity, mild acid pretreatment of the tissue sections was required to inactivate the alkaline phosphatase. Acid pre-treatment dramatically reduced the endogenous activity without affecting the efficiency of hybridization or the probe's ability to reveal a positive mRNA signal. Furthermore, the addition of polyvinyl alcohol to the substrate solution helped to keep the background staining low without adversely affecting the intensity of the signal. The current protocol allows rapid and sensitive detection of sites of gene expression in intestinal tissue.

Alkaline Phosphatase↗

PubMed1990

Localization of two calcium binding proteins, calbindin (28 kD) and parvalbumin (12 kD), in the vertebrate retina.

We used immunocytochemistry to locate two calcium binding proteins, calbindin (CaB) and parvalbumin (PV), in the retina of goldfish, frog, chick, rat, guinea pig, dog, and man. The location of CaB depended on the type of dominant photoreceptor cells in birds and mammals. In cone-dominant retinas such as those of the chick, CaB-like immunoreactivity was found in the cones, cone bipolars, and ganglion cells. Amacrine cells 5-12 microns across were also labeled. In rod-dominant retinas, such as those of the rat, guinea pig, and dog, horizontal cells, small amacrine cells (about 6 microns across), and cells in the ganglion cell layer were labeled. In the human retina, which has both cones and rods in abundance, cones, cone bipolars, ganglion cells, horizontal cells, and small and large amacrine cells were labeled. In the frog and goldfish, the level of CaB-like immunoreactivity was low. In the frog, a few cones, amacrine cells, and cells in the ganglion cell layer were labeled. No immunoreactive structures were seen in the goldfish retina. PV-like immunoreactivity was found in chicks, rats, and dogs. No such immunoreactive structures were seen in the other species. In the chick, only amacrine cells were labeled. In the rat, amacrine cells and several displaced amacrine cells were labeled. In the dog, in addition to amacrine cells and displaced amacrine cells, horizontal cells were strongly labeled. Thus, PV-like immunoreactivity was found in those elements relating to the modulation of the main pathway of the visual transmission system.

Animals↗