Life Sciences Commons^™

Spiral Structures In The Wall Of The Hepatic Venous System In The Dog, Shigenori Okada, Yoshikuni Ohta

Scanning Microscopy

Unique spiral structures, located in the wall of the hepatic venous system in the dog, were examined in the central veins and the hepatic venous branches, utilizing microvascular corrosion casting and freeze-fracture technique in scanning electron microscopy and transmission electron microscopy of tissue sections. The whole hepatic venous system was divided into 4 portions: the central, sublobular, collecting and branches of the hepatic veins. The central vein was spindle-shaped with several compressions. Removing the endothelial cells of the central vein, pathways of venous sinusoids were like a labyrinth. In the sublobular veins, spiral structures distinctly appeared as the diameter increased. …

Angiogenesis In The Gonadal Capillary Network Of The Chick Embryo, F. J. Pérez-Aparicio, A. Carretero, M. Navarro, J. Ruberte

Scanning Microscopy

Seventy-one chick embryos of both sexes at the 35 Hamburger and Hamilton (H-H) developmental stage were processed for scanning electron microscopy of vascular corrosion casts and of critical point dried specimens, as well as transmission electron- and light microscopy, in order to study the angiogenic structures. The gonadal subepithelial capillary network was located at the level of the tunica albuginea under the covering epithelium. The casts showed a densely-meshed capillary network and numerous sprouting (nodular protrusions or capillary sprouts) and non-sprouting (enlarged vessels and angiogenic holes) angiogenic structures that were randomly distributed and mixed. Four types of angio-genic holes were …

Examination Of Injected Specimens By Confocal Laser Scanning Microscopy And Scanning Electron Microscopy, A. Castenholz

Scanning Microscopy

Although corrosion casts commonly examined by scanning electron microscopy (SEM) offer good insights into the general arrangement of the microvasculature of certain organs, no information can be obtained from such specimens on special morphological data or dynamic events. Thus, most investigators are obliged to make their interpretations of cast structures only on the basis of indirect criteria. A synopsis, which considers the most important data in that respect, is given for the blood and lymphatic microvessels. Moreover, a methodological approach is introduced, based on the application of fluorescent resin, which allows the examination of cast structures in uncorroded specimens together …

Vascular Architecture Of The Lactating And Non-Lactating Teat Of The Bitch: A Scanning Electron- And Light Microscope Study, F. J. Pérez-Aparicio, V. Dantzer, M. Navarro, A. Carretero, J. Ruberte

Scanning Microscopy

Tissues from fourteen mammary glands of eight bitches were prepared for scanning electron microscopy of vascular corrosion casts and for histology to study the vasculature of the lactating and non-lactating teats. The densely-meshed mammary dermal capillary network formed ridges and troughs. The teat ducts were vascularized by a relatively densely-meshed capillary network which drained into veins longitudinally oriented to the ducts. Between eight and fifteen teat duct openings were seen on the tip of the teat, that were sometimes divided by a septum. The inner vascularization of the teat showed that the main papillary arteries divided into undulating secondary papillary …

Revascularization Of An Excisional Wound In Gingiva And Oral Mucosa. A Scanning Electron Microscopic Study Using Corrosion Casts In Rats, Nils J. Selliseth, Knut A. Selvig

Scanning Microscopy

The purpose of this study was to examine microvascular regeneration associated with gingival wound healing. A full-thickness piece of gingiva and oral mucosa was excised along the palatal aspect of the right maxillary first and second molars in 20 young Wistar rats. The contralateral side served as unoperated control. After 2, 4, 7, 10 or 20 days of healing, microvascular corrosion casts were produced and examined by scanning electron microscopy. At 2 days, vessels surrounding the wound were dilated and impressions representing sites of leukocyte margination were prominent in the walls of venules. Capillary buds were emerging from venules and …

Reply By A. Carretero Et Al., Ana Carretero, H. Ditrich, M. Navarro, H. Splechtna, J. Ruberte

Scanning Microscopy

Dear Editor,

The study of vascular casts in the embryo by means of the scanning electron microscope represents the main subject of our research. We fully agree with DeRuiter and Gittenberger-de Groot in that corrosion casting is a valuable tool to study the early angiogenesis in embryos.

Letter To The Editor By M.C. Deruiter And A.C. Gittenberger-De Groot Relating To: "Technical Improvements In Corrosion Casting Of Small Specimens: A Study On Mesonephric Tubules And Vessels Of Chicken Embryos." [By A. Carretero, H. Ditrich, M. Navarro, H. Splechtna, J. Ruberte, Scanning Microscopy Vol. 7(4), P. 1333-1338 (1993)]., M. C. Deruiter, A. C. Gittenberger-De Groot

Scanning Microscopy

Dear Editor,

The topic of scanning electron microscopy (SEM) investigation of casting of vessels in the embryo still holds our interest. We are particularly focused on the possibilities of early injection as a method to support angiogenesis and vasculogenesis research in the embryo. It is questionable whether our technique leads to unreliable results because of severe trauma to the embryo as suggested by the above mentioned authors. The lower success yield might very well be the result of the higher friability of the embryo in general in this young stage.

Diluted And Undiluted Mercox Severely Destroy Unfixed Endothelial Cells. A Light And Electron Microscopic Study Using Cultured Endothelial Cells And Tadpole Tail Fin Vessels, J. Gassner, A. Lametschwandtner, T. Weiger, H. C. Bauer

Scanning Microscopy

Mercox is a methylmethacrylate-based resin which is widely used for vascular corrosion casting with subsequent scanning electron microscopic analysis. In the present study the effect of undiluted and diluted Mercox (4+1; volume + volume; Mercox: monomeric methylmethacrylate (MMA); 0.02 g catalyst MA/ml Mercox) and methylmethacrylate with and without catalyst MA (0.625 g/10 ml MMA) on fixed and unfixed endothelial cells was studied. Light microscopy (LM) of cultured capillary endothelial cells (ECs), which were replicated with diluted or undiluted Mercox shows degranulation and membrane perturbation of ECs, while no morphological changes occur in glutaraldehyde-prefixed ECs. Scanning electron microscopy (SEM) of replicas …

Microvascular Corrosion Casting Of The Rat Mandibular Joint: A Technical Approach, Etienne Piette, Alois Lametschwandtner

Scanning Microscopy

The rat mandibular joint is a ginglymoarthrodial joint deeply hidden under the zygomatic process of the squamosal bone. This joint was studied by scanning electron microscopy (SEM) of microvascular corrosion casts in 47 adult rats. Six additional rats were injected with India ink and thick sections of the joint area were examined by light microscopy. The small size of the joint (2.5 mm x 1.5 mm in occlusion), the existence of two slit-like joint compartments, the close proximity of bones and soft tissues in a mobile structure, and the intimate relationships of the joint with adjacent skeletal muscles made the …

Different Forms Of Corrosion Casts, Seyedhossein Aharinejad, Peter Böck

Scanning Microscopy

We have previously described artifacts in corrosion casts prepared with Mercox®, diluted with methylmethacrylic acid (MMA). Using scanning electron microscopy (SEM) of casts and light microscopy (LM) of tissue sections, we found new forms of artifacts in casts prepared with both undiluted and MMA-diluted Mercox®. When undiluted Mercox® was used, most of the casts did not show artifacts. Artifacts were rarely seen and comprised empty casts consisting of a rim, while endothelial cell nuclear imprints and other vascular wall structures were replicated. Other casts sometimes showed vessels with a fine granular surface or some with conglomerates in their internal structure, …

The Microvasculature Of The Larynx: A Scanning Electron Microscopic Study, Peter Franz, Seyedhossein Aharinejad

Scanning Microscopy

In ten adult guinea pigs, the microvascular architecture of the larynx was evaluated using microvascular corrosion casts and scanning electron microscopy. The vocal cords were provided with a subepithelial capillary network. The capillaries, freely anastomosing with each other, were supplied and drained via strongly undulating arteries and veins. The undulation of the latter vessels may explain their adaptability to volume changes of the larynx during phonation. The vasculature of the internal perichondrium of the thyroid cartilage was interrupted at the anterior commissure where an avascular zone was present at the origin of the vocal cords. This avascular area is common …

The Microvasculature Of Human Infant Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection Ii. Palate And Lip, Q. X. Yu, K. M. Pang, W. Ran, H. P. Philipsen, X. H. Chen

Scanning Microscopy

The microvasculature of human hard and soft palate and lip originating from four infant males and six females, aged 6 months to 2 years was studied by scanning electron microscopy of vascular corrosion casts and light microscopy of India ink injected specimens. The capillary loops of the hard palate mucosa and vermilion border of the lips were found to be tall, numerous and consisted of primary, secondary and tertiary loops. Those of the soft palatal and labial mucosa were short, few in number and demonstrated a simple hair-pin shape originating directly from the subpapillary vascular network. It was concluded that …

Microvascular Pattern Of The Retina In The Japanese Monkey (Macaca Fuscata Fuscata), Shigenori Okada, Yoshikuni Ohta

Scanning Microscopy

The microvascular architecture of the retina in the Japanese monkey was revealed using scanning electron microscopy of microvascular corrosion casts.

At the optic nerve disc, the central retinal artery radiated to four primary retinal arterioles: the superior and inferior temporal arterioles and superior and inferior nasal arterioles. A dense retinal capillary network showed regional differences in density. The capillary networks observed were divided in four parts: the optic nerve disc, macula, equator, and ora serrata. At the optic nerve disc, the network was a multi-laminar structure containing the radial peripapillary capillaries in parallel with the nerve fibers at the innermost …

Ischemia/Reperfusion Injury Of The Ascending Colon In Ponies: A Correlative Study Utilizing Microvascular Histopathology And Corrosion Casting, B. J. Darien, P. A. Sims, W. C. Stone, D. R. Schilly, R. R. Dubielzig, R. M. Albrecht

Scanning Microscopy

Volvulus of the ascending colon (ACV) in the horse results in microvascular injury and necrosis of the intestinal mucosa. This study investigated the site and type of microvascular injury which occurs within the mucosa and sub mucosa following ACV. Histopathology of volvulus treated ponies demonstrated mucosa! necrosis with microvascular hemorrhage and thrombosis. Thrombi occurred within the subepithelial capillaries and edema and hemorrhage developed throughout the mucosa and submucosa. Vascular casts allowed 3-D viewing of samples obtained from the entire pelvic flexure and demonstrated two distinct microvascular changes: 1) disruption of the colonic glandular capillary network occurred concomitantly with the …

Casting With Mercox-Methylmethacrylic Acid Mixtures Causes Plastic Sheets On Elastic Arteries. A Scanning And Transmission Electron Microscopic Study, Seyedhossein Aharinejad, Peter Böck

Scanning Microscopy

Lungs and systemic vessels of rats were cast with Mercox, both undiluted and diluted with monomeric methylmethycrylate (MMA; v:v/4:1), and studied by scanning electron microscopy (SEM). A sheet, less than 5 μm thick, surrounded the surface of cast pulmonary arteries and the aorta, when using diluted Mercox. This envelope was absent when casts were prepared with undiluted Mercox. Transmission electron microscopy (TEM) of unmacerated cast arteries showed all constituents of the vascular wall. Sections of thoroughly macerated vascular casts, however, still showed elastic lamellae in the vascular wall region, whereas muscular components and endothelial lining were completely digested. It is …

Improved Tissue Corrosion Of Vascular Casts: A Quantitative Filtration Method Used To Compare Tissue Corrosion In Various Concentrations Of Sodium And Potassium Hydroxide, Paul A. Sims, Ralph M. Albrecht

Scanning Microscopy

In this study, we compare weights of filter retained material (11 μm particle retention) after solubilization and filtration of unfixed, un-perfused tissue (fat, liver and trachea) in sodium and potassium hydroxide (1% , 5%, 10% and 20% weight/volume, w/v) at 8, 24 and 48 hour time points at 45°C. Three detergents [1% Triton-X-100 (volume/volume, v/v), 1% 7X (v/v), 1% Terg-A-Zyme (w/v)] used in combination with hydroxide were evaluated for use in solubilizing fat. Additionally, vascular casts from mouse kidneys were corroded to test the practical effectiveness of corroding solutions on resin infused tissue.

Five percent KOH for eight hours proved …

Scanning Electron Microscopy Of Styrene-Methylethylketone Casts Of The Airway And The Arterial System Of The Lung, Teruyuki Hojo

Scanning Microscopy

The method of making casts of airways and the pulmonary arterial system using a styrene polymer resin is described. A human and a dog were used as models. The viscosity of this resin ranges between 40 and 60 dPa/s at 24°C. The elastic rubber tube used for resin injection allows a constant perfusion pressure, i.e., 44 mm Hg and 110 mm Hg for airway and vascular filling, respectively. The casts obtained using this method are suitable both for macro- and microscopic analysis. Shrinkage during polymerization is minimal. Moreover, a preceding lavage is not necessary. Scanning electron microscopy (SEM) of cast …

Mercox®-Methylmethacrylic Acid Mixture Penetrates Into Cells. A Scanning And Transmission Electron Microscopic Study, S. Aharinejad, P. Böck

Scanning Microscopy

During preparation of vascular casts using mixtures of Mercox® and methylmethacrylic acid for scanning electron microscopy, occasionally irregular structures were observed adhering to otherwise well prepared corrosion casts. These artifacts were further analyzed in sections of cast preparations. The bizarre-shaped structures varied in size and were often tightly connected to vascular casts; they withstood KOH maceration and cleaning with formic acid. The persistence of biological material, connective tissue fibers and cells or cellular fragments, became obvious in ultrathin sections. Transmission electron microscopy also showed inhomogeneity of the polymerized casting medium (Mercox®-methylmetbacrylate mixture; v/v: 4:1). An unidentified com-pound of this resin …

Luminal Constrictions On Corrosion Casts Of Capillaries And Postcapillary Venules In Rat Exocrine Pancreas Correspond To Pericyte Processes, Seyedhossein Aharinejad, Peter Böck

Scanning Microscopy

The rat exocrine pancreas was studied as a model to demonstrate morphological features of different types of capillaries, using scanning electron microscopy of vascular corrosion casts and transmission electron microscopy of tissue sections. Two types of capillaries were discerned. The first type represents less undulated, slender, straight capillaries with numerous, shallow, circular or semilunar furrows on its cast's surface. In tissue sections, this type probably corresponds to non-fenestrated capillaries. The numerous grooves on its cast correspond to pericyte processes beneath the endothelial lining. The second type comprises capillaries of an undulated course and variable diameter with less numerous furrows. In …

Appearance Of Venous Sphincters In The Pulmonary Microvascular Bed Of Normotensive And Spontaneously Hypertensive Rats, Seyedhossein Aharinejad, Peter Böck

Scanning Microscopy

The appearance of pulmonary venous sphincters was studied in normotensive and spontaneously hypertensive rats using scanning electron microscopy of microvascular corrosion casts and transmission electron microscopy of tissue sections. Vascular casts were prepared either after lavage with Tyrode solution or after glutaraldehyde prefixation. Pronounced pulmonary venous sphincters were more frequently identified in spontaneously hypertensive rats as compared to corresponding circular indentations in normotensive rats. Tissue sections established venous sphincters in hypertensive animals as consisting of multiple layers of smooth muscle cells in the venous walls. We did not observe any autonomic nerve terminals in close proximity to these bundles of …

The Opisthonephric Blood Vascular System Of The Chicken Embryo As Studied By Scanning Electron Microscopy Of Microvascular Corrosion Casts And Critical Point Dried Preparations, H. Ditrich, H. Splechtna

Scanning Microscopy

Microvascular corrosion casts of chicken embryos between four and 19 days after fertilization have been prepared. The developing kidney was investigated with scanning electron microscopy (SEM). The injection technique and resin composition were modified in order to facilitate the complete replication of native blood vascular systems of specimens as small as 15 mm body length. The development of the opisthonephros was followed from near the beginning of its function until a vascular development comparable to the adult situation was reached. Critical point dried glomeruli show the differentiation of the glomerular visceral epithelium (podocytes) from initially epithelioid to highly branched forms. …

Microcorrosion Casting In Normal And Pathological Biliary Tree Morphology, E. Gaudio, L. Pannarale, F. Carpino, G. Marinozzi

Scanning Microscopy

The organization of the intrahepatic biliary tree was studied in three dimensions by scanning electron microscopic (SEM) corrosion casts, in normal and cholestatic rat liver.

In the normal liver the observation revealed the features of the biliary passages from the bile canaliculi to the canaliculo-ductular junction, to the ductules and the bile ducts, confirming previous SEM observations.

In cholestatic liver, the modifications and the proliferation of bile ductules appear clearly.

Resin flow from canalicular to sinusoidal network was never observed.

The method was found to be very useful in the evaluation of the architecture of the intrahepatic biliary tree, under …

Scanning Electron Microscopy Of Vascular Corrosion Casts In Comparative Studies On Renal Vascular Structure, H. Ditrich, H. Splechtna

Scanning Microscopy

In comparative microcorrosion casting studies on renal vascular systems the following demands should be met: The preparation procedure (anaesthesia, operation, flushing of the blood vascular system, ...) should be in accord with the specific physiological properties of the animal under investigation and the casting procedure (injection, curing, maceration, ...) should be kept constant as far as possible. If these points are considered, comparative data, even of quantitative nature, can be obtained from corrosion casts. Examples of results at the organ, single vessel and intercellular level as well as correlation of the results with physiological data are given.

Vascular Changes In Popliteal Lymph Nodes Due To Antigen Challenge In Normal And Lethally Irradiated Mice, Douglas A. Steeber, Chris M. Erickson, Kees C. Hodde, Ralph M. Albrecht

Scanning Microscopy

The microvascular system of the murine popliteal lymph node was investigated using scanning electron microscopy of microcorrosion casts. Time-dependent changes in the microvasculature following regional antigen challenge in normal and lymphocyte-depleted mice were studied. Normal lymph node microvasculature exhibited a significant increase in both the vascular bed and post-capillary venules containing high-endothelium in response to antigen challenge. Lymph nodes of lymphocyte-depleted mice showed no microvascular size increase following antigen challenge and a reduction in the amount of high-endothelium was observed.