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Cardinal Veins (cardinal + vein)
Selected AbstractsThe para-aortic ridge plays a key role in the formation of the renal, adrenal and gonadal vascular systemsJOURNAL OF ANATOMY, Issue 6 2010Sumio Isogai Abstract Renal, adrenal, gonadal, ureteral and inferior phrenic arteries vary in their level of origin and in their calibre, number and precise anatomical relationship to other structures. Studies of the origin and early development of these arteries have evoked sharp disputes. The ladder theory of Felix, which states that ,All the mesonephric arteries may persist; from them are formed the phrenic, suprarenal, renal and internal spermatic arteries' has been generally quoted in the anatomical textbooks without rigorous verification for 100 years. In this study, we re-examined this theory by performing micro-injection of dye and resin into rat (Rattus norvegicus) embryos. Our results revealed that most of the mesonephric arteries had degenerated before the metanephros started its ascent. The definitive renal, adrenal, gonadal, ureteral and inferior phrenic arteries appeared as new branches from the gonadal artery and/or directly from the abdominal aorta to the para-aortic ridge. Coincidental to this, the anatomical architecture of the inter-renal vascular cage, which consists of the interlobar and arcuate arteries and their collateral veins, was completed within the developing metanephros. We demonstrated that the delicate renal vascular cage switched from the primary renal artery to the definitive renal artery and that the route of venous drainage changed from the posterior cardinal vein to the inferior (caudal) vena cava. [source] Origin of the Infrarenal Part of the Caudal Vena cava in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2008P. Cornillie Summary The vascular topography in the lumbar region of pig embryos and young fetuses was three-dimensionally reconstructed to study some controversial aspects of the origin and development of the infrarenal part of the caudal vena cava. Contrary to general belief, it was found that the supracardinal veins, which form the azygos veins in the thorax, do not take part in the construction of the caudal vena cava in the lumbar region. These veins do appear in the abdomen, but they are only involved in the formation of the lumbar and ascending lumbar veins. The infrarenal part of the caudal vena cava arises from the lumbar part of the right caudal cardinal vein. Whilst this venous pattern is established, the lumbar part of the left caudal cardinal vein disappears and its former location is occupied by large lymphatic connections between the cysterna chyli and the retroperitoneal mesenteric lymphatic sac. On the basis of these findings, a number of hypotheses on the development of anatomical variations of the caudal vena cava should be reconsidered. [source] Abnormal venous and arterial patterning in chordin mutantsDEVELOPMENTAL DYNAMICS, Issue 9 2007Emmanuèle C. Délot Abstract Classic dye injection methods yielded amazingly detailed images of normal and pathological development of the cardiovascular system. However, because these methods rely on the beating heart of diffuse the dyes, the vessels visualized have been limited to the arterial tree, and our knowledge of vein development is lagging. In order to solve this problem, we injected pigmented methylsalicylate resins in mouse embryos after they were fixed and made transparent. This new technique allowed us to image the venous system and prompted the discovery of multiple venous anomalies in Chord,/, mutant mice. Genetic inactivation of Chordin, an inhibitor of the Bone Morphogenetic Protein signaling pathway, results in neural crest defects affecting heart and neck organs, as seen in DiGeorge syndrome patients. Injection into the descending aorta of Chrd,/, mutants demonstrated how a very severe early phenotype of the aortic arches develops into persistent truncus arteriosus. In addition, injection into the atrium revealed several patterning defects of the anterior cardinal veins and their tributaries, including absence of segments, looping and midline defects. The signals that govern the development of the individual cephalic veins are unknown, but our results show that the Bone Morphogenetic Protein pathway is necessary for the process. Developmental Dynamics 236:2586,2593, 2007. © 2007 Wiley-Liss, Inc. [source] Three-dimensional reconstruction of the remodeling of the systemic vasculature in early pig embryosMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2008Pieter Cornillie Abstract Current research on angiogenesis and vascular regression is mainly focused on pathological conditions such as tumor growth and diabetic retinopathy, while a suitable physiological model to study the controlling factors in these processes is still lacking. The remodeling pattern of the embryonic vasculature into the adult configuration, such as the branchial arch arterial system developing into the aorta or the early embryonic veins building the caudal vena cava can potentially serve as a model. However, practical applications of the embryonic vascular patterning are impeded by the current controversy over the exact development of the caudal vena cava in mammals. To elucidate these ambiguities, specific developmental stages of vascular development in pig embryos were mapped by means of computer-assisted 3D reconstructions starting from histological serial sections of Bouin's fixed embryos. Special attention was given to venous segments in the lumbar region, as their origin and fate are equivocally described in literature. Here we demonstrate that these venous segments originate from the caudal cardinal veins which are forced to migrate during development into a more dorsal position due to the expansion of the developing metanephroi and the more dorsal relocation of the umbilical arteries. These findings are in contrast with the generally accepted theory that the venous segments in the lumbar region arise from newly formed veins that are located dorsal to the early caudal cardinal system. Microsc. Res. Tech., 2008. © 2007 Wiley-Liss, Inc. [source] Timeline and distribution of melanocyte precursors in the mouse heartPIGMENT CELL & MELANOMA RESEARCH, Issue 4 2008Flavia Carneiro Brito Summary Apart from the well-studied melanocytes of the skin, eye and inner ear, another population has recently been described in the heart. In this study, we tracked cardiac melanoblasts using in situ hybridization with a dopachrome tautomerase (Dct) probe and Dct -LacZ transgenic mice. Large numbers of melanoblasts were found in the atrioventricular (AV) endocardial cushions at embryonic day (E) 14.5 and persisted in the AV valves into adulthood. The earliest time Dct -LacZ-positive cells were observed in the AV endocardial cushions was E12.5. Prior to that, between E10.5 and E11.5, small numbers of melanoblasts traveled between the post-otic area and third somite along the anterior and common cardinal veins and branchial arch arteries with other neural crest cells expressing CRABPI. Cardiac melanocytes were not found in the spotting mutants Ednrbs-l/s-l and Kitw-v/w-v, while large numbers were observed in transgenic mice that overexpress endothelin 3. These results indicate that cardiac melanocytes depend on the same signaling molecules known to be required for proper skin melanocyte development and may originate from the same precursor population. Cardiac melanocytes were not found in zebrafish or frog but were present in quail suggesting an association between cardiac melanocytes and four-chambered hearts. [source] | ||||||||||