The distribution of insulin binding sites in the mouse was investigated by in vivo whole-body autoradiography. Male mice were injected intravenously with 125I-insulin in the absence of and, in the presence of, excess unlabeled insulin. Three, 6, 15, 30 and 60 minutes after injection, the animals were perfused and subjected to autoradiographic procedures. Specific insulin binding was observed in the choroid plexus, liver, gastrointestinal tract, spleen, pancreas, deferent duct, and Harderian gland. In the liver and spleen, the distribution of binding sites was heterogeneous. In the liver, the density of the binding was higher around the branches of the portal vein than around the central vein. In the spleen, the marginal zone exhibited a higher density than the white and red pulp. The kidney cortex, and the thyroid gland showed a high degree of insulin binding, but the binding was nonspecific. The binding of insulin to other tissues and organs, including the skeletal muscle and fat, was weak, and most of the binding was nonspecific.
In order to observe glucose transport into the brain, 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-6-deoxyglucose (NBDG), a non-metabolizable and fluorescent glucose analogue, was injected intravenously into mice. After ascertaining that this glucose analogue is non-metabolizable in the brain, the NBDG contents in the blood and brain were measured quantitatively by spectrofluorimetry at 0, 0.5, 2, 5, 10 and 30 min after intravenous injection. The NBDG content in the blood decreased markedly with time, whereas in the brain it rapidly decreased, then gradually increased after 2 min. Glucose transport into the hippocampus was observed with a confocal laser scanning microscope. At 0.5 min, NBGD was seen to be highly concentrated on the vascular wall. Using the confocal mode, it was found that the fluorescence was unevenly distributed on the microvessel wall, suggesting local differences of glucose transport in the vascular wall. At 5 min, the fluoresent intensity of the vascular wall was markedly decreased, whereas relatively intense fluorescence was observed in the cerebral parenchyma of the stratum lacunosum-moleculare and stratum pyramidale of Ca3. At 10 min, a weak fluoresence was diffusely distributed in the hippocampus. As to the localization of NBDG in the brain, capillary endothelium (luminal and abluminal membrane), basement membrane, and the feet of the astrocytes are discussed.
The present study was undertaken to understand the realities of cancer patients' and their family members' distresses and inquiries, including medical/physical, emotional/spiritual and social/economic problems, from scientific viewpoints. The initial step of the study was to develop the classification category for these distresses and inquiries
A simple and new technique was developed to ensure intimate contact of film with whole-body sections mounted on glass slides. Mice were injected with 125I-labeled insulin intravenousely.Whole-body frozen sections were prepared using adhesive tape along with a piece of dry paper and transferred to cold glass slides coated with egg albumin and glycerin. After freeze drying, a slide-mounted section was placed in a plastic bag, and brought into contact with the film. The bag was subsequently evacuated and sealed by a vacuum sealer. By this method, film maximum contact could be maintained with the section during exposure. Following development of the film, the section was stained and used for histological identification of tissues in the autoradiograph.A method for preparing whole-body sections for autoradiography and staining was previously reported (6), and is essentially the same as that developed by Kawamoto and Shimizu (3) who used adhesive tape with dry paper in place of cellulose backed (7) and cotton backed (10, 11) adhesive tape. These methods make possible the mounting of whole-body cryo-sections on the glass slides. The sections are pressed against X-ray films and stored for several days or weeks. To ensure that contact is even and uniform, the section and film are exposed in a press at slight pressure, generally using standard X-ray cassettes. However, in some cases, there is uneven contact between the section and film.In this paper, a simple and new method for autoradiography of whole-body sections mounted on glass slides is described. MATERIALS AND METHODSAnimals: Adult male mice of the ICR strain, weighing approximately 25 g, were fasted overnight with free access to water. Labeled compound: Porcine, 125I-TyrA24insulin (specific activity 81.4 TBq/mmol) purchased from New England Nuclear, Boston, MA, USA was used as the tracer for whole-body autoradiography and dissolved in Ringer's solution (462.5 kBq/ml). Sectioning: Radioactive insulin (185 kBq) was injected into the tail vein followed by immediately anaesthetizing the animals by intraperitoneal injection of sgdium pentobarbital. Three min later, the mice were purfused with Ringer's solution for 1 min through the left ventricle. The incised region for perfusion was then covered with 3% carboxymethyl cellulose (CMC) frozen by dry-ice powder, and the entire body of an animal was frozen in a mixture of dry-ice and acetone. The frozen animal was wiped with tissue paper, painted with 3% CMC, mounted on microtome stage with 6% CMC, and frozen by dry-ice snow. It was then placed on a microtome in a cryostat (LKB-2250, Sweden) adjusted at -20°C. Frozen whole-body sagittal sections (20 pm thick) of the mouse were prepared and mounted on cold glass slides previously coated with egg albumin and a glycerine mixture according to the methods of Shimono et al. (6). The sections were freeze-dried in the cryostat and brought to room temperature in a desiccator containing silica gel. Whole-body autoradiography: Each slide-mounted dry section to be brought into contac...
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