A steady efflux of ionic current predicts hind limb development in the axolotl

Prior to hind limb development, tadpoles of the western spadefoot frog Pelobates cultripes (Pelobatidae) and dart-arrow frog Phyllobates bicolor (Dendrobatidae) possess large clear cells in the basal layer of the epidermis. These cells closely resemble Kugelzellen (KZn) of larval clawed frog, Xenopus laevis (Pipidae) and share ultrastructural traits with Leydig cells (LCs) of Caudata and Caecilia. In both species, KZn possess a transparent cytoplasm and a remarkable peripheral cytoskeleton of tonofilaments: in the arrow frog tonofilaments form bands parallel to the cell surface, in the spadefoot frog thin bundles, arranged in a three-dimensional network. KZn combine turgor (resulting from the hydrated cytoplasm) with stiffness (from peripheral cytoskeleton), thus providing structural stability to the larval epidermis.

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Effects of laboratory ultraviolet radiation and natural sunlight on survival and development of Rana pipiens

Canadian Journal of Zoology ◽

10.1139/z00-040 ◽

2000 ◽

Vol 78 (6) ◽

pp. 1092-1100 ◽

Cited By ~ 16

Author(s):

Gerald T Ankley ◽

Joseph E Tietge ◽

Gary W Holcombe ◽

David L DeFoe ◽

Stephen A Diamond ◽

...

Keyword(s):

Uv Radiation ◽

Limb Development ◽

Hind Limb ◽

Rana Pipiens ◽

Life Stage ◽

Leopard Frog ◽

Natural Sunlight ◽

Survival And Development ◽

Full Intensity ◽

Environ Toxicol

Changes in solar ultraviolet (UV) radiation have been proposed as a possible factor contributing to seeming increases in hind-limb malformations in anuran amphibians in North America. One purpose of this study was to reproduce results from an earlier experiment (G.T. Ankley, J.E. Tietge, D.L. DeFoe, K.M. Jensen, G.W. Holcombe, E.J. Durhan, and S.A. Diamond. 1998. Environ. Toxicol. Chem. 17: 25302542) in which Rana pipiens (northern leopard frog) developed hind-limb ectromelia and ectrodactyly when exposed to an artificial source of UV radiation in the laboratory. Additionally, we sought to assess the effects of natural sunlight on survival and development in this species. Animals exposed to UV radiation in the laboratory from stage 2526 (just prior to hind-limb development) through forelimb emergence exhibited a dose-dependent elevation of hind-limb dysmorphogenesis. The observed malformations usually were bilateral and typically symmetrical, and consisted primarily of missing and reduced digits. Exposure of animals at this life stage to full intensity natural sunlight caused significant mortality, while exposure to screened sunlight (ca. 5060% of ambient) resulted in an elevated incidence of abnormal hind limb pathology (ectromelia, ectrodactyly) identical to that observed in organisms exposed to UV radiation in the laboratory. Owing to uncertainties in dose extrapolation, for example, in the context of animal behavior, the potential significance of our results in terms of explaining adverse effects in amphibians from the field is as yet unclear.

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Inhibition of eNOS by L-NAME resulting in rat hind limb developmental defects through PFKFB3 mediated angiogenetic pathway

Scientific Reports ◽

10.1038/s41598-020-74011-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Ziqiang Wu ◽

Huan Yao ◽

Huan Xu ◽

Yang Wang ◽

Wangming Hu ◽

...

Keyword(s):

Extracellular Matrix ◽

Endothelial Cells ◽

Smooth Muscle ◽

Smooth Muscle Cells ◽

Limb Development ◽

Hind Limb ◽

Critical Role ◽

Muscle Cells ◽

Developmental Defects ◽

Pregnant Rat

Abstract l-arginine/NOS/NO signaling pathway plays a critical role in controlling variety of vascular diseases. However, whether NOS inhibition by L-NAME suppresses late embryonic development is undefined. The aim of this study is to determine whether NOS inhibition by L-NAME is critical for late embryonic rat hind limb development. The pregnant rat at E13.5 administrated L-NAME by consecutive intraperitoneal injection. The embryos been harvested from E16.5 to E 20.5. Hematoxylin and Eosin Staining, Immunofluorescence and Immunohistochemistry performed to determine hind limb Vasculogenesis, HUVEC culture, Adenoviral PFKFB3 infection, Real time PCR and western blot were performed to determine whether l-arginine/NOS/NO pathway controlling late embryonic hind limb development through PFKFB3 mediated angiogenetic pathway. NOS inhibition by L-NAME resulting in late embryonic hind limb developmental defects characterized by severe hemorrhage. The in vivo studies showed that NOS inhibition strongly suppressed hind limb angiogenetic remodeling by impairing differentiation of endothelial cells and smooth muscle cells, and extracellular matrix synthesis. For underlie mechanism, our studies indicated that L-NAME treatment dramatically suppresses PFKFB3 expression in hematopoietic progenitor cells, tubulogenetic endothelial cells and smooth muscle cells. Knockdown of PFKFB3 dramatically inhibits the expression of angiogenetic genes, as well as tubulogenesis and extracellular matrix related genes. Taken together, our data in this study demonstrated that l-arginine-eNOS-NO pathway is important for rat hind limb development during late embryonic stage. This could be both a useful animal model and a promising therapeutic treatment for defects of late embryonic developmental hind limbs.

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Electron Microscopic Observations on the Basal Lamina of Chick Limb Buds After Trypsin and Edta Treatment

Journal of Cell Science ◽

10.1242/jcs.3.3.373 ◽

1968 ◽

Vol 3 (3) ◽

pp. 373-380

Author(s):

S. C. GOEL ◽

A. JURAND

Keyword(s):

Basal Lamina ◽

Salt Solution ◽

Limb Development ◽

Hind Limb ◽

Physiological Role ◽

Electron Microscopic ◽

Limb Buds ◽

Edta Treatment ◽

Subsequent Separation ◽

Calcium And Magnesium

Chick hind-limb buds were treated first with calcium- and magnesium-free balanced salt solution and then with either trypsin or EDTA. Treatment with these chemicals, and the subsequent separation of the ectodermal covering from the mesoderm, produces two different results as regards the basal lamina. In the case of trypsin, the lamina stays with the ectoderm but shows signs of probable tryptic digestion. After EDTA treatment the lamina stays with the mesoderm and becomes very loose and swollen. This loosening allows the structure of the otherwise compact lamina to be resolved so that banded collagen fibrils are seen participating in its substance. The above observations are discussed in relation to the mode of action of the two chemicals. The physiological role and the origin of the basal lamina, as well as the possible implications of the present findings to the question of limb development and morphogenesis, are also discussed. A note has also been made regarding the various terms used to describe the epitheliomesenchymal junction layers.

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Ultrastructural features of ectodermal–mesenchymal relationships in the developing limb of Xenopus laevis

Development ◽

10.1242/dev.31.2.287 ◽

1974 ◽

Vol 31 (2) ◽

pp. 287-303

Author(s):

D. Tarin ◽

A. P. Sturdee

Keyword(s):

Xenopus Laevis ◽

Limb Development ◽

Hind Limb ◽

Structural Features ◽

Microscopical Study ◽

Apical Region ◽

Clear Insight ◽

Electron Microscopical ◽

Morphogenetic Effects ◽

Insight Into

Electron microscopical study of the formation of the hind limb of the toad Xenopus laevis between stages 49 and 53 of larval development has been performed with special reference to the relationships between the apical ectodermal ridge and the underlying mesenchyme. It has been found that the intervening collagenous layer is thinner in the vicinity of the ridge than elsewhere and that the subjacent mesenchymal cells are more loosely arranged. There are also fewer mesenchymal filopodia crossing the collagenous layer than proximally although the distribution of delicate vertically disposed threads, also observed at the ecto-mesenchymal junction, is uniform over the entire bud. Overall, it is concluded that the fine structural features of Xenopus limb development, during these stages, do not give clear insight into the mechanisms by which the apical region exerts its morphogenetic effects.

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Heterochronic differences of Hoxa-11 expression in Xenopus fore- and hind limb development: Evidence for lower limb identity of the anuran ankle bones

Development Genes and Evolution ◽

10.1007/s004270050172 ◽

1998 ◽

Vol 208 (4) ◽

pp. 175-187 ◽

Cited By ~ 43

Author(s):

Maria J. Blanco ◽

Bernhard Y. Misof ◽

Günter P. Wagner ◽

M. J. Blanco ◽

B. Y. Misof ◽

...

Keyword(s):

Lower Limb ◽

Limb Development ◽

Hind Limb ◽

Limb Identity

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Depression of Collateral Blood Flow Following Arterial Thrombosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651903 ◽

1977 ◽

Vol 38 (04) ◽

pp. 0850-0862 ◽

Cited By ~ 1

Author(s):

Robert G. Schaub ◽

Ronald Sande ◽

Kenneth M. Meyers

Keyword(s):

Blood Flow ◽

Arterial Thrombosis ◽

Hind Limb ◽

Therapeutic Interventions ◽

Collateral Blood Flow ◽

Serotonin Antagonist ◽

Limb Perfusion ◽

Clinical Consequences ◽

Collateral Vessels ◽

Iliac Bifurcation

SummaryPermanent ligation of the feline aorta at the iliac bifurcation is followed by rapid opening of pre-existing collateral blood vessels. However, if ligation is combined with formation of a clot, these protective collateral vessels do not function. This study was undertaken to determine if drugs which alter serotonin function can improve collateral blood flow after arterial thrombosis. Permanent ligations were placed at the iliac bifurcation, circumflex iliac and sixth lumbar arteries in all cats. A clot was produced in the aorta of 27 cats by injection of 0.1 ml of thromboplastin. Ligated clot-occluded cats were untreated (10); had blood serotonin depleted using a single dose of reserpine (0.1 mg/kg i. m.) followed by para-chlorophenylanine (p-CPA) (100 mg/kg orally) every 3 days (9) ; or were treated prior to surgery with a serotonin antagonist cinanserin HC1 (4 mg/kg i. v.) (8). Control cats (18) were acutely ligated. 9 of these cats were untreated, 5 were cinanserin HC1-treated, and 4 were reserpine/p-CPA-treated. Extent of collateral development was assessed by aortograms 3 days after occlusion and by neurologic rating. Aortograms of acutely ligated cats indicated a significant collateral blood flow around the segment of ligated aorta, while ligated clot-occluded cats had a severely depressed hind-limb perfusion. Reserpine/p-CPA-treated ligation clot-occluded cats had aortograms similar to acutely ligated cats. The cinanserin HC1-treated ligation clot-occluded cats had aortograms which indicated hind-limb perfusion was not as adequate as the acutely ligated cats. However, the perfusion of these animals was improved over untreated ligation clot-occluded cats. Neurologic rating correlated with aortograms. These results suggest: 1) the clinical consequences of arterial thrombosis cannot be entirely attributed to mechanical occlusion of an artery, but may be due to depression of protective collateral blood flow induced by thrombosis, 2) serotonin is an important factor in this depression of collateral blood flow, and 3) isolation of the factors responsible for collateral inhibition could permit the development of therapeutic interventions.

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Macroanatomical Structure of the Lumbosacral Plexus and its Branches in the Indigenous Duck

Bangladesh Veterinary Journal ◽

10.32856/bvj-2018.01 ◽

2018 ◽

Vol 52 (1-4) ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

MT Hussan ◽

MS Islam ◽

J Alam

Keyword(s):

Hind Limb ◽

Femoral Nerve ◽

Morphological Structure ◽

Spinal Nerve ◽

The Body ◽

Lumbar Plexus ◽

Lumbosacral Plexus ◽

Sacral Plexus ◽

Spinal Nerves ◽

Femoral Cutaneous Nerve

The present study was carried out to determine the morphological structure and the branches of the lumbosacral plexus in the indigenous duck (Anas platyrhynchos domesticus). Six mature indigenous ducks were used in this study. After administering an anesthetic to the birds, the body cavities were opened. The nerves of the lumbosacral plexus were dissected separately and photographed. The lumbosacral plexus consisted of lumbar and sacral plexus innervated to the hind limb. The lumbar plexus was formed by the union of three roots of spinal nerves that included last two and first sacral spinal nerve. Among three roots, second (middle) root was the highest in diameter and the last root was least in diameter. We noticed five branches of the lumbar plexus which included obturator, cutaneous femoral, saphenus, cranial coxal, and the femoral nerve. The six roots of spinal nerves, which contributed to form three trunks, formed the sacral plexus of duck. The three trunks united medial to the acetabular foramen and formed a compact, cylindrical bundle, the ischiatic nerve. The principal branches of the sacral plexus were the tibial and fibular nerves that together made up the ischiatic nerve. Other branches were the caudal coxal nerve, the caudal femoral cutaneous nerve and the muscular branches. This study was the first work on the lumbosacral plexus of duck and its results may serve as a basis for further investigation on this subject.

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