Recent technological advances of the CCD (Charge-Coupled Device) video-probe have made microscopes more compact and greatly improved their sensitivity. Additionally, this progress has enabled researchers to utilize such devices for clinical application. We newly designed a compact capillaroscopy which was composed with a CCD video-probe equipped a contact-type objective lens and illuminator. In the present study, we evaluated usefulness of the instrument for a bed-side human capillaroscopy to observe the capillary flow in various dermal regions. The influences of tissue compression on the dermal capillary blood flow were also investigated to confirm the utility for clinical applications. Our capillaroscopy visualized the nutritional capillary blood flow in almost all parts of skin surface. The video images to visualize the dermal capillary flow in the nail-fold of the middle finger during tissue compression are shown in the motion pictures. All nutritional capillary loops run parallel to the skin surface, and can be clearly visualized in their full length. By increasing the loaded vertical stress at 40 mmHg, which value might be slightly higher than capillary pressure, all capillaries could not be collapsed and the erythrocytes in all capillaries are still flowing. Our observations showed that a level of vertical stress similar to arterial pressure was required to stop the capillary flow. From these demonstrations the present CCD video-probe based capillaroscopy would be useful for clinical applications as a bed-side human capillaroscopy.

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The detailed lymphatic architecture in various organs is relatively unknown. In this paper, we report the lymphatic architecture beneath the buccal mucosa, which is classified as a lining mucosa like that of the inferior surface of the tongue, using enzyme histochemical staining and serial section 3D reconstruction by computer graphics. As a result, the lymphatic network beneath the buccal mucosa at the molar part formed a fixed flow to the collecting lymphatics on the muscle layer. In other words, this network was formed like a network of rivers in which the lymph constantly flowed from narrow into wider lymphatic vessels without stagnation. The shape of the blind ends from the lymphatic network beneath the buccal mucosa resembled a glomerulus. This means that the absorption efficiency of the glomerular blind ends of the lymphatic vessels is higher than that of the simple loop blind end in the tongue. [MVRC 1(1): 9-11, 2007]

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We previously reported that the average velocity of RBC in single capillaries in anesthetized rat cerebral cortex measured at 250 frame/s was 1.43±1.03 mm/s under physiological conditions. Since we have noticed that the apparent average velocity tends to be higher when the frame (sampling) rate is increased, we investigated in detail the velocity profile at different frame rates. In anesthetized rats, intravenously injected FITC-labeled RBCs were detected in the intraparenchymal tissue through a cranial window at 125, 250 and 500 frames/s with a high-speed laser-scanning confocal fluorescence microscope. RBC velocity and number of RBCs were automatically calculated with Matlab® domain our own software (KEIO-IS2). The RBC velocity in capillaries was found to be dependent upon frame rate, with average values of 0.85±0.43 mm/s at 125 frames/s, 1.34±0.73 mm/s at 250 frames/s and 2.09±1.81 mm/s at 500 frames/s. The velocity distribution was similar among different rats and most values lay within a relatively small range around 1.0 mm/s at any frame rate examined. We conclude that some RBCs, which flow at high speed, are missed at lower frame rates. [MVRC 1(1): 12-15, 2007]

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A cranial window was opened in 5 urethane-anesthetized Wistar rats to examine directly the effect of Gosha-jinki-gan (GJG), a Kampo medicine, on the microvascular hemodynamics in the cerebral cortex, using a new high-speed confocal fluorescence microscope combined with our image analysis software, KEIO-IS1 and KEIO-IS2. Blood pressure did not change during the experiments. The vessels had a baseline diameter of 10.40±1.78μm, and were dilated to 13.45±2.68μm (124±15 %) at 60 minutes (p<0.05 (paired t test)) and to 12.05±2.76μm (112±15 %) at 120 minutes (p=0.38). Cerebrocortical tissue blood flow (CBF) was 1.80±0.49 sec^-1 (reciprocal second, used as an arbitrary relative flow unit) before GJG administration, and increased to 2.06±0.49 sec^-1 (116±9 %) at 60 minutes (p<0.05) and to 2.28±0.84 sec^-1 (125±13%) at 120 minutes (p<0.05). RBC velocity was 3.67±1.39 mm/sec at baseline, and increased to 4.45±1.04 mm/sec (158±62 %) at 60 minutes (p<0.05) and to 4.28±1.39 mm/sec (162±99 %) at 120 minutes (p=0.069). Thus, GJG dilated vessels in the brain, increased CBF in the microvasculature, and increased RBC velocity in intraparenchymal capillaries, though the mechanisms involved remain unidentified. [MVRC 1(1): 16-19, 2007]

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