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Biomedical subjects

T Teranishi

Publications and source records attributed to T Teranishi.

At least 37 records · Page 2Linked to original sources
PubMed1991

Induction of immunoreactive proliferating cell nuclear antigen (PCNA) in goldfish retina following intravitreal injection with tunicamycin.

Effects of a photoreceptor-specific biotoxin, tunicamycin (TM), injected intravitreally into the goldfish eye at one side, were explored on electroretinograms (ERGs) and proliferating cell nuclear antigen-immunoreactive (PCNA-ir) nuclei, representing the mitotic activity of rod precursors, in the retina at both sides. The eye-cup preparations were made for ERG recording, and the retinas were isolated and processed as cryosections or wholemounts by a routine immunohistochemical method for visinin (cones), opsin (rods), tyrosine hydroxylase (dopaminergic cells) and proliferating cell nuclear antigen (PCNA), at various intervals after intravitreal injection with TM (1.0 micrograms/eye). On some thin sections, autoradiographic study was combined following intravitreal injection with [3H]thymidine (TdR, 0.1 microCi/eye). The dose of TM used heavily destroyed cones and rods only in the treated retinas 2-15 days after injection, the photoreceptors being renewed for further 15-20 days. Approximately in parallel, ERGs were largely impaired 2-10 days after TM injection and recovered for 10-20 days. However, intravitreal TM altered the distribution and density of PCNA-ir nuclei in both treated and untreated retinas. The density of PCNA-ir nuclei reduced at first (on days 1 and 2), and then clustered and rapidly increased on days 3-5 and maintained at high levels with diffuse distribution over the whole area, particularly in the treated retinas, up to 60 days after TM injection; the maximum peak of 3.7 and 20 times the initial level was seen on day 20 in the outer nuclear layer (ONL) and inner nuclear layer (INL), respectively. PCNA-ir nuclei were found to be abundant in the ONL even after the photoreceptors and ERGs had been restored in the treated retinas on day 20, suggesting a kind of overproduction of retinal cells. The autoradiographic study provided comparable results to those obtained with PCNA immunohistochemistry. The mechanism by which damage to the treated retina causes rod precursor cells to proliferate in the untreated retina remains unresolved.

Animals↗
PubMed1991

Induction of proliferating cell nuclear antigen (PCNA)-immunoreactive cells in goldfish retina following intravitreal injection with 6-hydroxydopamine.

1. The dopaminergic neurotoxin, 6-hydroxydopamine (6-OHDA), was injected intravitreally into the eyes of juvenile (5- to 6-cm) goldfish. 2. Proliferation of rod neuroblasts caused by 6-OHDA (2 micrograms in 2 microliters saline) was detected in retinal wholemounts by immunofluorescence for proliferating cell nuclear antigen (PCNA) 3, 7, 14, 20, or 30 days after injection. 3. The injected dose of 6-OHDA was sufficient to cause permanent loss of dopaminergic interplexiform and serotonergic amacrine cells in the injected eye but not in the contralateral control eye. 4. 6-OHDA increased the density (mm-2) of PCNA-ir cells in the outer nuclear layer (ONL) of the injected eye to 2.65 times the initial density 20-30 days after injection, and it increased the density of PCNA-ir cells in the ONL of the contralateral, untreated eye, equally but after a delay of less than or equal to 7 days with respect to the injected eye. 5. 6-OHDA also increased the density of PCNA-ir cells in the inner nuclear layer (INL) to greater than 20 times the initial density 7 days after injection, followed by a rapid decline almost to control levels by 14 days after injection. 6. The sequence of responses to 6-OHDA, with PCNA-ir cells first scattered in the ONL and then clustered in the INL, suggests that neuroblasts from the ONL migrate to the INL to compensate for toxin-induced cell loss. 7. Double staining for 5-bromodeoxyuridine (BrUdR; a thymidine analogue) and PCNA, carried out on 7 days after intravitreal injection with 6-OHDA, showed that 77% of all PCNA-ir cells in the outer nuclear layer had been in S phase during the previous 24 hr. 8. Immunoreactivity for PCNA was found to be a valid marker for rod neuroblasts which have entered S phase within 1-2 days before sampling and was shown to be especially convenient for investigating the distribution of proliferating cells in whole mounts. 9. In controls injected unilaterally with saline or saline plus 1% dimethyl sulfoxide (DMSO), the differences in densities of PCNA-ir rod precursor nuclei 2-30 days after injection vs. day 0 (uninjected) were statistically insignificant in both injected and uninjected eyes (Negishi et al., 1991). Therefore the local effect of injecting 6-OHDA was due to 6-OHDA itself, not to mechanical damage or nonspecific actions of foreign substances.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Dendritic morphology of a class of interstitial and normally placed amacrine cells revealed by intracellular Lucifer yellow injection in carp retina.

The dendritic morphology of a class of interstitial amacrine (ISA) and normally placed amacrine cells was investigated in carp retina. We first identified their fluorescent nuclei after preloading with 4,6-diamidino-2-phenylindole (DAPI) in living or aldehyde-fixed retinal wholemounts and then injected them iontophoretically with Lucifer Yellow (LY) under microscopic control. Although DAPI appeared to be accumulated nonspecifically by amacrine and ganglion cells, ISA cell nuclei were discriminated by focusing between the amacrine and ganglion cell layers. The fusiform cell bodies of LY-injected cells were located in the middle of the inner plexiform layer (IPL), and the 4-5 stout primary dendrites were monostratified in sublamina b of the IPL and decorated with spines and long thin processes. The average spatial properties of these cells were approximately: density, 6.0 cells/mm2; intersomatic distance, 400 microns; dendritic field size, 0.27 mm2; dendritic coverage, 1.6. The dendritic interconnections were made of tip-to-tip or tip-to-side contacts between dendrites and between a dendrite and thin process, forming many closed loops. The ISA cells belong to a morphological type Fnb. A class of normally placed amacrine cells with dendritic morphology similar to that of the ISA cells was also found by LY injection in wholemounts. These cells belong to a morphological type Fna, with dendrites monostratified in sublamina a of the IPL in a 0.35-mm2 dendritic field. The ISA (Fnb) and Fna cells appear to represent a matched pair of cell types that are similar in structure but complementary in function.

Animals↗
PubMed1990

Emergence and development of immunoreactive cells in teleostean retinas during the perinatal period.

We have used light-microscopical immunohistochemistry to investigate developmental changes of several neurochemical indicators in retinas of perinatal killifish and goldfish. Immunoreactive proliferating cell nuclear antigen (ir-PCNA/cyclin, a marker for replicating cells) was present in nuclei of all neuroblasts in the early monolayer stage, but was lost progressively in central-to-peripheral and proximal-to-distal order as the layers and cells of the mature retina appeared. The loss of ir-PCNA was slightly prior to the appearance of ir-TH (tyrosine hydroxylase), GAD (glutamic acid decarboxylase) and GS (glutamine synthetase) at the 4th embryonic day (E4) in both fish. Since hatching was earlier in goldfish (E5) than in killifish (E7), neurochemical maturation was evident at 2-3 days before hatching in killifish but not until around hatching in goldfish. Two markers, ir-somatostatin and protein kinase C, were detected by the 1st postnatal day (H1) in goldfish, but not in perinatal or adult killifish retinas. Thus the course of development of killifish and goldfish retinas is similar, but not identical. The validity of ir-PCNA as a marker for proliferating cells is confirmed by the coincidence of its disappearance with the appearance of neurochemical markers for mature, postmitotic retinal cells.

Aging↗
PubMed1990

Close tip-to-tip contacts between dendrites of transient amacrine cells in carp retina.

In isolated retinas of the carp (Cyprinus carpio) placed receptor side up in a plastic chamber, a subclass of amacrine cells, generating a fast ON-OFF transient response to spot and annular light stimuli, were intracellularly recorded and injected with a fluorescent dye, Lucifer yellow (LY). After brief fixation of the same preparations in aldehyde solution, the retinas were wholemounted vitreous side up in a tissue chamber. Under a fluorescence microscope, one LY-injected cell and several dye-coupled cells were seen; these cells belonged to type Fnd, having a fusiform soma, narrow dendritic field and bistratified dentrites in the inner plexiform layer (IPL). To reveal the interconnections between dendrites, one of such dye-coupled cells was further injected with LY. Close tip-to-tip contacts were predominantly found between dendrites of neighboring type Fnd cells in sublaminae a and b of the IPL, respectively.

Animals↗
PubMed1990

Sequential course of uptake of intravitreal 5,7-dihydroxytryptamine by carp retinal cells.

The sequential course of uptake by retinal cells of intravitreally injected 5,7-dihydroxytryptamine (5,7-DHT) together with dopamine (DA) was investigated in juvenile carp retinas, which were removed at various intervals (1-24 h) after injection. The cells taken up 5,7-DHT were visualized immunohistochemically with anti-serotonin (5-HT) antibody and FITC-conjugated IgG. After a mixture of 5,7-DHT and DA (2.5, 10 or 20 micrograms each) was given, large-sized indoleamine (IA) amacrine cells first (1-4 h), and then small-sized indoleamine-accumulating amacrine amacrine (IAA) cells (4-12 h), bipolar cells (8-12 h) and in some cases photoreceptor cells (12-24 h) were sequentially observed, and finally the immunoreactive structures almost disappeared around 24 h after injection. When the mixture of 5,7-DHT and DA (10 micrograms each) was injected into the eyes of reserpinized fish, the same sequential uptake of 5,7-DHT was seen in a faster time course, but additionally various classes of retinal cells (horizontal, ganglion and Müller cells) became visible as irregular clusters. However, DA cells were never visualized at any stages of all the experiments, indicating that DA cells do not take up 5,7-DHT in the carp retina, which was further confirmed by double labeling of 5-HT- and tyrosine hydroxylase-like immunoreactive cells. Double labeling also revealed that 5,7-DHT-accumulating bipolar cells appear to represent a subclass different from that of protein kinase C-like immunoreactive bipolar cells.

5,7-Dihydroxytryptamine↗
PubMed1989

Dendritic morphology of retinal dopamine cells in carp of different sizes.

The dendritic morphology of dopamine (DA) cells in the inner plexiform layer of the retina of different-sized carp (8.6-33.6 cm in body length) was investigated by identifying their fluorescent cell bodies in isolated, aldehyde-fixed flatmounts and injecting them iontophoretically with Lucifer yellow (LY) under microscopic control. DA cells for LY injection were chosen in an intermediate region between the optic disc and the retinal margin, and their spatial parameters (cell density, nearest neighbor distance, dendritic field size and dendritic coverage) were compared between retinas of different sizes to explore whether this region is simply stretched by tissue expansion during retinal growth. It was shown that as the fish grow larger the dendritic field size of DA cells increases while the cell density is sharply reduced and the dendritic coverage gradually decreases. Differences in the dendritic coverage of DA cells between certain fish groups with different sizes were statistically significant. Further, the irregularity in cell distribution appeared to increase as the fish became larger. These results suggest that the dendritic tree of individual DA cells in the intermediate region is developed not only by tissue expansion but also by other unknown factors.

Animals↗
PubMed1988

Dopamine cells and rod bipolar cells contain protein kinase C-like immunoreactivity in some vertebrate retinas.

The localization of cells immunoreactive to a monoclonal antibody against protein kinase C (PKC) and to polyclonal antibodies against tyrosine hydroxylase (TH) was investigated in the retina of fish (carp, goldfish, dace and catfish), frog, turtle, chick and some mammalians (guinea pig, rat, cat and rabbit) by means of fluorescence microscopy. PKC-like immunoreactivity was found in dopamine (DA) or TH-like immunoreactive (IR) cells in all the species examined and also in rod bipolar cells in the fish (except for catfish), and in presumed rod bipolar cells in the other animals (except for frog and turtle). In the catfish, frog and turtle retinas, no PKC-like IR bipolar cells were found. In the rat retina, some other amacrine cells in addition to TH-like IR amacrine cells were reactive to the anti-PKC antibody. It is of interest that PKC-like immunoreactivity is commonly found in DA cells and probably in rod bipolar cells in most animal species, although the functional significance is unknown at present.

Animals↗
PubMed1988

Regional difference in the dendritic morphology of dopamine cells in carp retina.

The dendritic morphology of dopamine (DA) cells in the inner plexiform layer of the retina of carp (body length, ca. 33 cm) was investigated by identifying their fluorescent cell bodies in isolated, aldehyde-fixed flat-mounts and injecting them iontophoretically with Lucifer yellow CH under microscopic control. Attention was paid to clarifying regional differences in their dendritic morphology. In the marginal zone within 0.25 mm from the retinal edge, the density of DA cells was extremely high (120 cells/mm2), their dendrites tended to extend in parallel with the retinal circumference, and the dendritic field size was small (2.5 X 10(-2) mm2). As the injection point was shifted centrally by steps, the dendrites of DA cells tended to extend toward the optic disc and subsequently toward the margin, finally forming a round or oval dendritic field for each cell. Concomitantly with such changes in the dendritic field, the cell density sharply decreased to about 30 cells/mm2, and the dendritic field size increased to 10 X 10(-2) mm2 in a zone 2-3 mm interior to the margin. However, the dendritic coverage factor was consistently about 3.0 over the entire retinal field. Such morphological changes observed sequentially from the retinal margin to the intermediate region represent a developmental course of DA cells in the carp retina.

Animals↗
PubMed1988

GABAergic inhibition on dopamine cells of the fish retina: a [3H]dopamine release study with isolated fractions.

Inner retinal cells including dopamine (DA) cells were isolated and fractionated from the carp (Cyprinus carpio) retina by an enzyme cell dissociation and metrizamide gradient centrifugation method. When gamma-aminobutyric acid (GABA) antagonists (bicuculline and picrotoxin) were added into the perfusate over such a cell fraction, they stimulated the release of [3H]DA which had been preloaded in the cell fraction. The action of GABA antagonists was dose and Ca2+ dependent. Their minimal effective concentration was very low (0.5 microM). A similar action was elicited by high K+. In the presence of excess GABA, this stimulatory action of GABA antagonists and high K+ on [3H]DA release was completely abolished. To interpret the action of GABA antagonists on DA cells, isolated cell fractions were preincubated with GABAse. After such a treatment, the stimulatory effects of GABA antagonists and high K+ on [3H]DA release were differentiated from each other; the former disappeared whereas the latter remained unchanged. The data strongly suggest that GABA inhibits the DA release from retinal DA cells and thus the GABA antagonists affect [3H]DA release from cell fractions not by a direct membrane action but by a disinhibition mechanism via GABA receptors on the DA cell bodies.

4-Aminobutyrate Transaminase↗
PubMed1987

Two types of lamprey retina photoreceptors immunoreactive to rod- or cone-specific antibodies.

The localization of structures immunoreactive to antisera against opsin (OPS; a specific marker for rods) and against visinin (VIS; a specific marker for cones in the vertebrate retina) was investigated in the retina of the river lamprey (Lampetra japonica) by means of fluorescence microscopy. Different immunoreactive structures were found with the two antisera. A vitreadly located structure in the outer nuclear layer displayed OPS-like immunoreactivity, while a scleradly located one exhibited VIS-like reactivity. Thus, the two antisera applied to the retina of the river lamprey permit the distinguishing of rod and cone immunoreactive photoreceptors such as occurs typically in all vertebrate classes. The former appears in the outer segments of a type of rod cells, and the latter in the cell bodies and axons of cones.

Animals↗
PubMed1987

Paradoxical induction of dopaminergic cells following intravitreal injection of high doses of 6-hydroxydopamine in juvenile carp retina.

Histofluorescence studies were conducted on two groups of juvenile carp (body length, 12.7 and 6.6 cm on the average, respectively) during certain periods (3-11 months) of retinal growth, to evaluate the destructive effect of 6-hydroxydopamine on dopaminergic and indoleamine-accumulating cells. Within a certain range of doses (0.1-5.0 micrograms/eye) of the neurotoxin injected intravitreally, it was found to destroy both classes of cells in a dose-dependent manner: more cells disappeared with higher doses. However, a high dose (5-25 micrograms/eye) of the neurotoxin caused paradoxical events in the retina, inducing an appearance of clustered dopaminergic cells with various soma sizes and abnormally high regional density, disturbed laminar organization, and a facilitated growth rate at the retinal margin. A preliminary examination with [3H]thymidine labelling suggests that the high dose of 6-hydroxydopamine may cause severe damage to certain classes of cells including dopaminergic and indoleamine-accumulating cells, and that a metamorphic change of precursor cells (neuroblasts) in the outer nuclear layer is responsible for the induction of such abnormal dopaminergic cells as clusters.

Age Factors↗
PubMed1987

Dendritic morphology of indoleamine cells revealed by intracellular injection of lucifer yellow in fixed carp retina.

The dendritic morphology of indoleamine amacrine cells in carp retina was investigated by identifying their fluorescent cell bodies by preloading with noradrenaline followed by iontophoretic injection of Lucifer Yellow in isolated and aldehyde-fixed preparations under microscopic control. Although two subpopulations of serotonin-like immunoreactive amacrine cells (small and large in soma size) were found, small cells were not seen in aldehyde-fixed preparations. Cells preloaded with noradrenaline corresponded to large immunoreactive cells and were labeled with Lucifer Yellow. The cell bodies labeled were located at the innermost level of the inner nuclear layer, and gave rise to three to five primary dendrites which branched frequently and were found mainly in sublamina a of the inner plexiform layer. These cells examined in an intermediate region between the optic disc and the retinal periphery were pyriform in soma shape while dendritic fields were found or oval covering an area of 0.18 +/- 0.05 mm2 (510 +/- 80 microns in diameter). Cell density in this region was about 32 cells/mm2 and, therefore, their dendritic field coverage was approximately 6.0.

Animals↗
PubMed1987

Functional and morphological correlates of amacrine cells in carp retina.

Experiments were conducted on isolated retinas of adult carp (Cyprinus carpio) to investigate correlations between photoresponses and morphological features of amacrine cells. The fluorescence dye Lucifer Yellow CH was iontophoretically injected into single cells which had been characterized electrophysiologically. Photoresponses were classified into two main types (transient ON-OFF and sustained), which were further subgrouped into "fast" and "slow" ON-OFF types and into ON-center and OFF-center types, respectively. In the spectral response curve, all the types dealt with showed a maximum response at 621 nm, indicating that main input signals derive from red-sensitive cones. The cells marked by intracellular injection of the dye showed a great variety in morphology. Cells were classified into 8 subtypes, based on soma shape (fusiform or pyriform), dendritic field area (narrow, less than 0.3 mm2; medium, 0.3-0.8 mm2; wide, greater than 0.8 mm2), and dendritic stratification in the inner plexiform layer (restricted to sublamina a or b, or distributed diffusely). In certain cases a given response type was correlated with a specific morphological type, while receptive field size was not strictly correlated with dendritic field areas. Long and fine peripheral "axon-like" processes were found to arise from the primary dendrites of most fusiform cells. Dye-coupling was found among cells which appear to belong to the same cell category.

Action Potentials↗