SEARCH · Search PubMed

Results for “RADIOAUTOGRAPHY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

PubMed1977

A modified technique for combination of cytochemistry and radioautography of haemic cells.

Cultured mouse bone marrow and human blood cells were labelled with 3H-thymidine, smeared, and stained, using peroxydase reagents or the May-Grünwald Giemsa procedure. The slides were dipped in a approximately 12% solution of polyvinylchloride, bleached by a photographic fixer and processed for liquid emulsion radioautography. This method yielded technically very satisfactory radioautographs of pre-stained smears.

Animals↗

PubMed1966

Location of sites of 5-hydroxytryptamine storage and metabolism by radioautography.

1. A technique for the radioautographic identification, localization, and study of the turnover of cellular depots of 5-hydroxytryptamine (5-HT) has been evaluated. A light microscopic survey was made of the uptake and turnover of 5-HT, synthesized in vivo from its administered tritium-labelled precursor, 5-hydroxytryptophan (5-HTP).2. 5-HT was taken up rapidly and retained for long periods of time by adrenal medullary chromaffin cells, gastric enterochromaffin cells, blood platelets, thyroid parafollicular cells, beta cells of pancreatic islets, mast cells, and septal cells of the lung. Reticulo-endothelial cells of liver and spleen took up radioactive 5-HT more slowly but also retained it for days.3. Specific uptake, and a rapid turnover of radioactive 5-HT, was found in pancreatic exocrine cells, neurones of the superior cervical ganglion, terminal axons of gastro-intestinal myenteric plexus, carotid body cells, and pinealocytes.4. A supranuclear localization of radioactive 5-HT in renal proximal tubular cells may represent tubular secretion of 5-HT.5. The localization of 5-HT by radioautography generally corresponds to that found by formaldehyde-induced fluorescence. It makes possible the study of 5-HT turnover and is capable of greater resolution than the fluorescence technique. Freeze-drying may also be avoided.

5-Hydroxytryptophan↗

PubMed1969

Electron microscopic radioautography: identification of origin of synaptic terminals in normal nervous tissue.

A method combining intraocular injection of tritiated leucine and electron microscopic radioautography has been used to study the distribution of optic nerve terminals in the monkey lateral geniculate nucleus. Radioactive label is found in only one type of synaptic terminal, which demonstrates that this terminal is of retinal origin and that this approach can be used to study the origin of synaptic terminals in normal tissue.

Animals↗

PubMed1989

A reevaluation of the distribution of 3H-proline in the transseptal ligament of the mouse in radioautography.

It is generally accepted that there is uniform collagen metabolism within the periodontal and transseptal ligaments. The present study suggested regional variations in the incorporation and removal of 3H-proline within the transseptal ligament in radioautography, suggesting variable rates of collagenous protein remodeling coincident with physiological tooth movements. Highest numbers of silver grains were over the middle third of the ligament during both incorporation and removal phases (p less than 0.001). Rates of grain removal were greater in the middle than in mesial or distal thirds (p less than 0.001). The half-life of labeled proteins was significantly less in the middle than in mesial or distal thirds (p less than 0.005). Because there were no significant regional differences in cell numbers, regional variability in grain incorporation and removal within the transseptal ligament likely indicates regional differences in cellular synthetic or degradative activity coincident with remodeling of the transseptal ligament during physiological drift and suggests that the center of this ligament may experience more stress and, thus, remodels more rapidly.

Animals↗

PubMed1976

Study of the surface secretion of the bronchiole using radioautography.

The purpose of the present study was to obtain further information regarding the chemical nature and cell of origin of the surface secretion of the bronchiole using radioautography after the injection of labeled leucine, glucosamine, galactose. Rat lungs were perfused with mammalian Ringer's solution with added albumin. A 10-min pulse of L-leucine labeled with hydrogen-3 was administered, followed by perfusion with nonradioactive solution for 15 min to 4 hours. Similar studies were performed with [3H] glucosamine and [3H] galactose. Heavy labeling of the Clara cells of bronchioles was obtained after injection of [3H] L-leucine. Labeling of alveolar wall cells was also obtained. Labeling of the surface of the bronchiole was much heavier than the labeling of the surface of the alveoli. No specific labeling of bronchiolar cells was obtained with [3H] glucosamine and [3H] galactose. The results provide added evidence for the protein nature of the surface layer of the bronchiole and for the Clara cell as its cell of origin.

Animals↗

PubMed1972

Quantitative radioautography of sugar transport in intestinal biopsies from normal humans and a patient with glucose-galactose malabsorption.

Both galactose accumulation and phlorizin binding by columnar epithelial cells have been investigated in vitro with a recently developed technique for high-resolution, plastic-section radioautography which is particularly suited to small quantities of biopsy tissue. Grain density analysis of the radioautographs provides definitive support for the view that the cellular mechanisms underlying glucose-galactose absorption in laboratory animals are fully applicable to the small intestine of man. Even the number of sugar carriers at the microvillar membrane appears similar and the major quantitative difference, lower affinity for phlorizin in man, correlates with the finding that phlorizin is also a less potent inhibitor of uphill, galactose transport at the microvilli. In addition, radioautographs of biopsies taken 2 yr apart from a patient with glucose-galactose malabsorption provide evidence that the cellular defect in this inborn error of transport is a persistent reduction in the number of functioning sugar carriers at the microvillar membrane.

Adult↗

PubMed1980

Radioautography of dexamethasone in rabbit gingiva and buccal mucosa.

The localization of 3H-dexamethasone in gingiva and in buccal mucosa was investigated radioautographically after systemic administration of the labeled glucocorticoid to rabbits. Tissue samples were processed for dry radioautography of diffusible substances. This study demonstrates localization of 3H-dexamethasone in the nuclei of target cells in the gingival epithelium, stromata, and the walls of blood vessels, and to a lesser degree in the buccal mucosa cells. The findings support the possibility of a direct effect of glucocorticoids via specific hormone cytosol-nuclear receptors in oral tissues.

Animals↗

PubMed1980

An attempt at quantitation of procollagens I and III and of collagen IV in tooth sections by exposure to the corresponding antibodies followed by 125I-protein A and radioautography.

The immunoreactivity of procollagen types I and III and of collagen type IV was detected in frozen sections of the growing apical end of rat incisor teeth by an indirect method making use of protein A. The sections were exposed to affinity-purified antibodies against these substances. The bound antibodies were then detected by incubation with radioiodinated protein A, followed by radioautography. This immunoradioautographic approach yielded preparations with low background, in which the reactions could be quantitated by counts of silver grains. The distribution of the radioautographic reactions was essentially the same as that previously observed with direct and indirect peroxidase methods, that is, procollagen I antigenicity predominated in odontoblasts and predentin, with minor amounts in periodontal tissue and pulp; procollagen III antigenicity was present in periodontal tissue and, to a lesser extent, in the pulp; and collagen IV antigenicity was restricted to basement membranes. Moreover, grain counts provided quantitative support for the conclusions on the distribution of procollagen I and III antigenicity.

Animals↗

PubMed1980

Polypeptide hormone receptors in vivo: demonstration of insulin binding to adrenal gland and gastrointestinal epithelium by quantitative radioautography.

A tissue-screening survey employing quantitative radioautography was carried out at 2 min after the intravascular injection of 125I-insulin into laboratory rats. The results revealed a substantial binding of insulin to cells forming the proximal convoluted tubule in kidney, hepatocytes of liver, acinar cells of the pancreas, parenchymal cells of the adrenal cortex and medulla, and epithelial cells of the gastrointestinal tract. Control experiments indicated that this binding was due to a specific interaction with the insulin receptor, except in the case of kidney where the binding was shown to be nonspecific. Although the major target for insulin action (liver) clearly demonstrated specific insulin binding, several other classical targets (adipocytes, skeletal, cardiac, and smooth muscle cells) showed no specific 125I-insulin binding and therefore indicated the limits of sensitivity of the in vivo radioautographic method. Nevertheless, the working hypothesis of a direct correlation of insulin receptor density with insulin action points to the hitherto unemphasized targets of pancreas, adrenal gland, and gastrointestinal tract as major sites of insulin action in the body.

Adipose Tissue↗

PubMed1984

An improved method for freeze-fracture radioautography of tissues and cells, as applied to duodenal epithelium and thymic lymphocytes.

An improved method has been devised for the localization of radioactive substances to either one of the leaflets of cellular membranes. After tissue specimens are freeze-fractured and covered with a platinum-carbon replica, they are freeze-dried to allow coating with radioautographic emulsion at room temperature. After exposure at 4 degrees C and development, the emulsion is protected by layers of carbon and grease before the tissue underlying the replica is dissolved in sodium hypochlorite. The grease is removed in Freon 14 and the replica with its emulsion cover is mounted on a specimen grid for electron microscopic examination. The accuracy of radioactivity localization was demonstrated using 3H-thymidine-labeled liver by finding silver grains over the same sites after freeze-fracture as after thin section radioautography. Tests with 3H-methacrylate revealed that the interposition of a platinum-carbon replica decreased the radioautographic reaction by over 80%; hence, the need for long exposure. Only 67% of the silver grains came from radiation sources located beyond the upper 0.05 micron of the specimen and, therefore, the emulsion could be affected by radiation sources located not only within membrane leaflets but also in nearby cytoplasm. Thus, when 3H-fucose was injected into rats to locate newly formed glycoproteins within intestinal epithelium membranes, some of the silver grains found over E and P faces might be produced by radiation coming from the adjacent cytoplasm. To localize label within membrane leaflets in the absence of radiation sources in the cytoplasm, lymphocyte suspensions were incubated with 3H-concanavalin A at 0 degrees C. The plasmalemma radioactivity was then restricted to the two membrane leaflets, with 87-93% of the silver grains on the E leaflet and 7-13% on the P leaflet. It appears that, under these conditions, the technique provides adequate localization of radioactivity to the leaflets of the cell membrane.

Animals↗

PubMed1984

Block-staining tissues with potassium ferrocyanide-reduced osmium tetroxide and lead aspartate for electron microscopic radioautography.

In the hope of devising a method for prestaining tissues en bloc for electron microscopic radioautography, pieces of radioiodine-labeled liver were taken through various combinations of ferrocyanide-reduced osmium tetroxide, lead aspartate, and aqueous uranyl acetate at room temperature or at 60 degrees C. Following the tests, the method adopted for routine use was to block-stain tissues for 2 hr in potassium ferrocyanide-reduced osmium tetroxide at 4 degrees C followed by 1 hr in Walton's lead aspartate at room temperature. This simple method, which requires no manipulation before or after emulsion coating and development of the radioautographs, provides adequate contrast without inducing background fog or artifacts.

Animals↗

PubMed1978

DNA replication studies in genus Vicia through fibre radioautography.

An experiment has been conducted to study the mode of replication in 3 species of Vicia having different C-values by means of fibre radioautography. Characteristics of the units involved in DNA replication of these species have been compared. It has been observed that replication occurs predominantly through bidirectional chain growth, replicating units are arranged in tandem, and replication proceeds from the point of origin in both directions. It has also been shown that there is a positive, though not proportionate, correlation between replication rates, the sizes of replication units and C-values.

Autoradiography↗

PubMed1985

The origin of prespore vacuoles in Dictyostelium discoideum cells as analysed by electron-microscopic immunocytochemistry and radioautography.

Prespore vacuoles (PSVs) are specifically formed in prespore cells of the cellular slime moulds and contain spore-specific antigens. We have examined the processes of PSV formation in Dictyostelium discoideum, using both the methods of immunoelectron microscopy with antispore serum and electron-microscopic radioautography with [3H]fucose, which is specifically incorporated into prespore cells. When prespore cells begin to differentiate at the late aggregation stages the Golgi apparatus, consisting of stacked cisternae and numerous vesicles, becomes conspicuous. Vesicles and flat sacs containing fibrous and membranous materials, respectively, are derived from Golgi cisternae. Spore antigens are found in these structures as well as in immature and mature PSVs. Fucose is incorporated into the same structures. When prespore differentiation is completed, the Golgi cisternae almost disappear and both antigens and fucose are localized in mature PSVs. The Golgi apparatus is scarcely observable in prestalk cells. Moreover, a similar pattern of changes in the Golgi apparatus and related structures occurs during the re-differentiation of prespore cells within prestalk isolates. It is concluded from these findings that PSVs are derived from the Golgi apparatus, the development of which is closely related to the differentiation of prespore cells.

Autoradiography↗

PubMed1999

Study of the effects of aging on macromolecular synthesis in various organ systems using microscopic radioautography.

In order to elucidate the effects of aging on macromolecular synthesis such as DNA, RNA, proteins, glucides and lipids in various organ systems of experimental animals and humans, systematic studies using light and electron microscopic radioautography in various organ systems including skeletal, muscular, digestive, respiratory, urinary, reproductive, endocrine, circulatory, nervous and sensory systems were studied after incorporation with macromolecular precursors. The experimental animals used were mainly ddY strain mice from embryo to postnatal days 1 and 3, weeks 1 and 2 or months 1, 2 and 6 months up to 1 and 2 years senescent stages. Animals were injected with [3H]-thymidine for DNA, [3H]-uridine for RNA, [3H]-amino acids for proteins, [3H]-glucose, [3H]-glucosamine and [35S]O4 for glucides, [3H]-glycerol for lipids and some low molecular target tracers such as hormones, inorganic substances and drugs. Results demonstrate that these precursors when incorporated into various cell types in various organs showed specific patterns of macromolecular synthesis as observed in perinatal to juvenile, mature and senescent stages. These effects of aging could answer some of the questions as to how but not why we get old.

Aging↗

PubMed1983

Sites of RNA synthesis and migration in the adrenal cortex cells of the young rat, as shown by radioautography.

The sites of RNA synthesis, processing and migration were studied with light and electron microscope radioautography in adrenal zona fasciculata cells of the young rat. Animals were injected iv with [3H]uridine and sacrificed at various time intervals. A marked radioactive peak was found in blood at the 20 min interval, later time intervals being considered as chase periods. Labelling was high over nucleoli of fasciculata cells at 1 h, with the silver grains concentrated over the fibrillar component. Simultaneous though lower peaks occurred over the condensed chromatin and the interchromatin space. Nucleolar and extranucleolar values were decreased at 8 and 24 h, most silver grains overlaying the cytoplasm at this time period. At 8 h, the granular component of the nucleolus was more heavily labelled than the fibrillar component. This sequence of events suggests a relatively slow uptake of the labelled nucleotides and slow formation of pre-rRNA molecules in the fibrillar component of the nucleolus, with the processing into smaller subunits occurring in the granular component during initial chase. Extranucleolar RNAs were synthesized simultaneously but in a smaller rate. Most nucleolar RNA was finally transferred to the cytoplasm. This pattern will serve as a basis for studying the effects of ACTH on the different steps of RNA synthesis and transport in adrenal cortex cells.

Adrenal Cortex↗

PubMed1986

Effects of ACTH on RNA synthesis and migration in the adrenal cortex cells of the young rat, as shown by radioautography.

The effect of ACTH on the RNA synthesis in adrenal zona fasciculata cells of the young rat were studied by light and electron microscope radioautography. Two units of ACTH were administered sc to animals and immediately followed by an iv injection of [3H]uridine. ACTH-injected and control rats, which received the isotope alone, were sacrificed at various time intervals. Labelling over extranucleolar areas was higher in the ACTH-treated animals at 20 min, then becoming lower than in the controls at 60 min and 24 h. Nucleolar radioactivity, however, was consistently decreased by ACTH at all experimental times. Apart from these changes in the rate of synthesis, the over-all curves of labelling were similar to those in the control animals with a striking peak at 1 h. The short-term increase in extranucleolar RNA synthesis observed after ACTH injection was considered to be consistent with the hypothesis that an enhanced extranucleolar synthesis of mRNA takes place early in stimulated animals and is associated with the synthesis of steroidogenic proteins. On the other hand, the relatively decreased uridine uptake of the label by the nucleolus in ACTH-treated animals, suggests an inhibition of nucleolar transcription with diminished pre-rRNA formation in treated animals.

Adrenal Cortex↗

PubMed1998

Quantitative receptor radioautography in the study of receptor-receptor interactions in the nucleus tractus solitarii.

The nucleus tractus solitarii (NTS) in the dorsomedial medulla comprises a wide range of neuropeptides and biogenic amines. Several of them are related to mechanisms of central blood pressure control. Angiotensin II (Ang II), neuropeptide Y (NPY) and noradrenaline (NA) are found in the NTS cells, as well as their receptors. Based on this observation we have evaluated the modulatory effect of these peptide receptors on alpha 2-adrenoceptors in the NTS. Using quantitative receptor radioautography, we observed that NPY and Ang II receptors decreased the affinity of alpha 2-adrenoceptors for their agonists in the NTS of the rat. Cardiovascular experiments agreed with the in vitro data. Coinjection of a threshold dose of Ang II or of the NPY agonists together with an ED50 dose of adrenergic agonists such as NA, adrenaline and clonidine counteracted the depressor effect produced by the alpha 2-agonist in the NTS. The results provide evidence for the existence of an antagonistic interaction between Ang II AT1 receptors and NPY receptor subtypes with the alpha 2-adrenoceptors in the NTS. This receptor interaction may reduce the transduction over the alpha 2-adrenoceptors which can be important in central cardiovascular regulation and in the development of hypertension.

Angiotensin II↗

PubMedDate not supplied

Study on RNA synthesis in the retina and retinal pigment epithelium of mice by light microscopic radioautography.

With the aim of determining the distribution of the incorporation of 3H-uridine in both retina and retinal pigment epithelium (RPE), the mouse eyes at embryonic day 9.5 (E 9.5), E 12.5, E 14.5, E 16.5, E 18.5 of gestational ages, and postnatal day 1 (P 1), P 3, P 7, P 14 were analyzed by light microscopic radioautography. Small pieces of the ocular tissues were labelled with 3H-uridine in vitro and light microscopic radioautographs were prepared. The average grain numbers per cell of the respective regions of tissues were calculated. In the retina, the grain numbers increased gradually from E 9.5 to P 1 and reached the maximal value at P 1, and then decreased until P 14. However, the grain numbers were more in the vitreal portion than those in the scleral portion at E 16.5 and then became more in the scleral portion from E 18.5 to P 14. It is considered that the ganglion and bipolar cells finish the RNA synthesis earlier, while the photoreceptor cells do it later during the fetal and postnatal development. In the RPE, the grain numbers gradually increased from E 12.5 to P 7 and then decreased until P 14. Considering the same ages, the grain numbers increased in the following order, anterior, equatorial and posterior regions during embryonic stages, but decreased in the same order after birth. Therefore, it is suggested that the activity of RNA synthesis in PE cells is higher in the posterior region than in the anterior region during embryonic stages. But the activity ascends generally and becomes relatively higher in the anterior region, after birth. Comparing the retina and RPE, it was noted that the grain numbers in the RPE were more important than in the retina and that the maximal value was at P 1 in the retina, while it was at P 7 in the RPE. From these results, it can be concluded that the RNA synthesis ceases earlier in the retina than in the RPE.

Aging↗