Fluoreszenzmikroskopischer Nachweis biogener Monoamine in der Epiphysis cerebri von Rana esculenta und Rana pipiens

1970 ◽  
Vol 111 (4) ◽  
pp. 550-558 ◽  
Author(s):  
Ch. Owman ◽  
C. R�deberg ◽  
M. Ueck
Keyword(s):  
Rana Pipiens ◽  
Rana Esculenta

Large retinal ganglion cells that form independent, regular mosaics in the ranid frogs Rana esculenta and Rana pipiens

1997 ◽  
Vol 14 (6) ◽  
pp. 1109-1127 ◽  
Author(s):  
K. M. Shamim ◽  
F. Scalia ◽  
P. Tóth ◽  
J. E. Cook
Keyword(s):  
Rana Pipiens ◽  
Nearest Neighbor ◽  
Ganglion Cells ◽  
Plexiform Layer ◽  
Rana Esculenta ◽  
Population Based ◽  
Inner Plexiform Layer ◽  
High Regularity ◽  
Large Trees ◽  
Cell Dimensions

AbstractPopulation-based studies of ganglion cells in retinal flatmounts have helped to reveal some of their natural types in mammals, teleost fish and, recently, the aquatic mesobatrachian frog Xenopus laevis. Here, ganglion cells of the semiterrestrial neobatrachian frogs Rana esculenta and Rana pipiens have been studied similarly. Ganglion cells with large somata and thick dendrites could again be divided into three mosaic-forming types with distinctive stratification patterns. Cell dimensions correlated inversely with density, being smallest in the visual streak. Cells of the αa mosaic (<0.2% of all ganglion cells) had the largest somata at each location (often displaced) and their trees were confined to one shallow plane within sublamina a of the inner plexiform layer. In regions of high regularity, many trees were symmetric. Elsewhere, asymmetric, irregular trees predominated and their dendrites, although sparsely branched, achieved consistent coverage by intersecting in complex ways. Cells of the αab mosaic were more numerous (≈0.7%) and had large somata, smaller (but still large) trees, and dendrites that branched extensively in two separate shallow planes in sublaminae a and b. The subtrees did not always match in symmetry, and each subtree tessellated independently with its neighbors. Cells of the αc mosaic (≈0.1%) had large, orthotopic somata and large, sparse trees (often asymmetric and irregular) close to the ganglion cell layer. Nearest-neighbor analyses and spatial correlograms confirmed that each mosaic was regular and independent. Densities, proportions, sizes, and mosaic statistics are tabulated for all three types, which are compared with types defined by size and symmetry in R. pipiens, by discriminant analysis in R. temporaria, by physiological response in both, and by mosaic analysis in Xenopus and several teleosts. The variable stratification of these otherwise similar types across species is consistent with other evidence that stratification may be determined, in part, by functional interactions.

Observations on the origin of the ‘germinal cytoplasm’ in Xenopus laevis

Development ◽  
1969 ◽  
Vol 22 (2) ◽  
pp. 229-251
Author(s):  
Renata Czołowska
Keyword(s):  
Xenopus Laevis ◽  
Germ Cells ◽  
Rana Pipiens ◽  
Rana Temporaria ◽  
Primordial Germ Cells ◽  
Rana Esculenta ◽  
Bufo Bufo ◽  
Discoglossus Pictus ◽  
Early Appearance ◽  
Vegetative Pole

The early appearance of the ‘germinal cytoplasm’ and its behaviour during the formation of cells which are thought to represent the primordial germ cells have been described in detail for Rana temporaria by Bounoure (1927, 1934, 1939) and Blackler (1958). These observations were extended to Xenopus laevis (Nieuwkoop, 1956; Nieuwkoop & Faber, 1956; Blackler, 1958), Bufo bufo (Blackler, 1958), Rana pipiens (Berardino, 1961), Discoglossus pictus (Gipouloux, 1962 a) and Rana esculenta (Hammer, cited by Blackler, 1965 b). The above findings agree with respect to the earliest detection of the ‘germinal cytoplasm’. Its first appearance was noticed as early as in the fertilized, unsegmented egg, where small, distinctly staining islands of cytoplasm are localized just under the cell membrane in an area around the vegetative pole of the egg. During cleavage the ‘germinal cytoplasm’ is distributed between the vegetative blastomeres directly surrounding the vegetative pole.

Comparative Morphology of Intercellular Bridges Between Developing Germ Cells of the Ovary

1970 ◽  
Vol 28 ◽  
pp. 328-329
Author(s):  
J. R. Ruby ◽  
R. F. Dyer ◽  
R. G. Skalko ◽  
R. F. Gasser ◽  
E. P. Volpe
Keyword(s):  
Germ Cells ◽  
Rana Pipiens ◽  
Comparative Morphology ◽  
Dense Material ◽  
Individual Species ◽  
Microscope Examination ◽  
Electron Dense Material ◽  
Intercellular Bridges ◽  
Cytoplasmic Side ◽  
Intercellular Connections

An electron microscope examination of fetal ovaries has revealed that developing germ cells are connected by intercellular bridges. In this investigation several species have been studied including human, mouse, chicken, and tadpole (Rana pipiens). These studies demonstrate that intercellular connections are similar in morphology regardless of the species.Basically, all bridges are characterized by a band of electron-dense material on the cytoplasmic side of the tri-laminar membrane surrounding the connection (Fig.l). This membrane is continuous with the plasma membrane of the conjoined cells. The dense material, however, never extends beyond the limits of the bridge. Variations in the configuration of intercellular connections were noted in all ovaries studied. However, the bridges in each individual species usually exhibits one structural characteristic seldom found in the others. For example, bridges in the human ovary very often have large blebs projecting from the lateral borders whereas the sides of the connections in the mouse gonad merely demonstrate a slight convexity.

The application of video-enhanced constrast/differential interference constrast microscopy in conjunction with whole mount electron microscopy to the study of organelle transport

1988 ◽  
Vol 46 ◽  
pp. 66-67
Author(s):  
J. H. Hayden
Keyword(s):  
Electron Microscopy ◽  
Rana Pipiens ◽  
Silver Film ◽  
Immunofluorescence Microscopy ◽  
Organelle Transport ◽  
Linear Element ◽  
Whole Mount ◽  
Carbon Coated ◽  
Linear Elements ◽  
Dic Microscopy

In a previous study, Allen video-enhanced constrast/differential interference constrast (AVEC-DIC) microscopy was used in conjunction with immunofluorescence microscopy to demonstrate that organelles and vesicle move in either direction along linear elements composed of microtubules. However, this study was limited in that the number of microtubules making up a linear element could not be determined. To overcome this limitation, we have used AVEC-DIC microscopy in conjunction with whole mount electron microscopy.Keratocytes from Rana pipiens were grown on glass coverslips as described elsewhere. Gold London Finder grids were Formvar- and carbon coated, and sterilized by exposure to ultraviolet light. It is important to select a Formvar film that gives a grey reflection when it is floated on water. A silver film is too thick and will detract from the image in the light microscope.

THE GAMETOKINETIC ACTIVITY OF SEROTONIN IN THE MALE OF RANA ESCULENTA

1962 ◽  
Vol 40 (3_Suppl) ◽  
pp. S146 ◽  
Author(s):  
B. Salvadori ◽  
G. Cagnazzo ◽  
G. Bernardini
Keyword(s):  
Rana Esculenta
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