Die Veränderungen der Plasmakolloide bei der Entwicklungserregung des Seeigeleies

Runnström, John

doi:10.1007/bf01608005

Cited by 104 publications

(13 citation statements)

References 56 publications

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“…Though only few applications have been made these are of interest and are briefly listed as follows: The red cell envelope (Schmitt et al , 1938 has been shown to possess lipoids and proteins oriented in much the same fashion as in the typical invertebrate axon sheaths. Similar effects may be observed in the membranes of certain marine eggs and tissue cells (Runnstrom, 1928(Runnstrom, , 1929; unpublished experiments by the authors). The nuclear membrane of fresh nerve cells shows a clear polarization cross of sign typical of protein, no lipoid being detectable after addition of media of high refractive index (Chinn, 1938).…”

Section: ) Cellular and Nuclear Membranes In Generalsupporting

confidence: 66%

The Ultrastructure of the Nerve Axon Sheath

1939

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Summary 1. In avoiding certain inherent indeterminacies in classical morphological methods and in obtaining further details regarding the microscopic and ultra‐microscopic structure of nerve axon sheaths, the methods of polarization optics and X‐ray diffraction are of great value. In the case of the myelin sheaths of vertebrate nerve fibres, for example, the optical and diffraction studies indicate the structure of the living fibre's sheath to be of smectic mixed fluid‐crystalline nature. The structure is, therefore, readily altered by chemical treatment to form the artifacts commonly observed in histological preparations. 2. A number of considerations suggest that the specific configuration of the lipoid and protein components of the myelin sheath is as follows. The proteins occur as thin sheets wrapped concentrically about the axon, with two bimolecular layers of lipoids interspersed between adjacent protein layers. While this means that in a radial direction within the cylindrical sheath there are alternate predominantly aqueous and predominantly hyirocarbon phases, the latter cannot be described as being entirely “non‐aqueous” 3. Polarization optical studies show that, contrary to the general view, invertebrate nerve fibres quite widely possess, aside from connective tissue investments, thin sheaths which are essentially similar in ultrastructure to the well‐defined myelin sheaths of vertebrate fibres. The demonstration of this fact involved a reinterpretation of the meaning of Gothlin's metatropic reaction, in which immersion of the fibre in media of high refractive index permits the (intrinsic) birefringence of lipoids present in the normal sheath in an oriented condition to become apparent by the reduction of the masking (form) double refraction of protein. Associated with the invertebrate metatropic axon sheaths are cells similar to the Schwann cells of vertebrate fibres. 4. Quantitative birefringence studies have disclosed that the axon sheaths of a wide variety of fibre types differ chiefly with respect to the relative amounts of oriented protein and lipoid present. This difference is observed not only between typical invertebrate and vertebrate fibres, but also when the fibres of a single vertebrate nerve are compared. For example, the curve obtained when sheath birefringence of frog sciatic fibres is plotted against fibre diameter shows wide variations in the magnitude of double refraction, changing continuously from birefringence due preponderantly to lipoids, in the case of the larger fibres, to that which, in the smallest fibres, results primarily from proteins. The transition from lipoid to protein predominance occurs at a fibre diameter of about 2μ., agreeing well with the division between “medullated” and “non‐medullated” fibres arrived at by histologists. It has been suggested that the low concentration of lipoid in the sheaths of small fibres is related to physical factors opposing the introduction of the lipoids into cylindrical structures of high curvature. 5. Examination of available inform...

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Section: ) Cellular and Nuclear Membranes In Generalsupporting

confidence: 66%

The Ultrastructure of the Nerve Axon Sheath

1939

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“…Most parthenogenetic agents produce cytolysis when ap lied for longer periods or a t higher concentrations. Compatheir detachment in immature sea urchin eggs (Runnstrom, 1928), a pinching-off of amoeboid vesicles free of granulated endoplasm may occur in gastrula cells and in early erythrocytes of amphibians which have been briefly exposed to alkali or other agents which a t higher concentrations decompose the cell membrane. Mechanical irritation may likewise cause a fragmentation of the embryonic cell.…”

Section: Constriction Of the Cell Membrane Resulting In Cytoplasmic Dmentioning

confidence: 99%

Significance of the Cell Membrane in Embryonic Processes

Holtfreter

1948

Annals of the New York Academy of Sciences

116

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“…Since the pioneering work of Runnstrom (26) and Schmidt (31,32), the mitotic figures of many kinds of living cells have been known to be birefringent. Improvement of polarization microscope technique has made it possible to measure the variation of birefringence retardation within the mitotic apparatus (MA) and its change during mitosis (34,35) .…”

mentioning

confidence: 99%

Quantitative studies on the polarization optical properties of living cells II. The role of microtubules in birefringence of the spindle of the sea urchin egg.

Hiramoto¹,

Hamaguchi²,

Shoji³

et al. 1981

The Journal of Cell Biology

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Birefringence of the mitotic apparatus (MA) and its change during mitosis in sea urchin eggs were quantitatively determined using the birefringence detection apparatus reported in the preceding paper (Hiramoto et al ., 1981, J. Cell Biol. 89 :115-120) . The birefringence and the form of the MA are represented by five parameters : peak retardation (SP), trough retardation (St), interpolar distance (D,), the distance (D 2 ) between chromosome groups moving toward poles, and the distance (D 3) between two retardation peaks. Distributions of birefringence retardation and the coefficient of birefringence in the spindle were quantitatively determined in MAs isolated during metaphase and anaphase . The distribution of microtubules (MTs) contained in the spindle was determined in isolated MAs assuming that the observed birefringence of the spindle is attributable to the form birefringence caused by regularly arranged MTs. The distribution coincided fairly well with the distribution of MTs in isolated MAs determined by electron microscopy. Under the same assumption, the distribution of MTs in the spindle in living cells during mitosis was determined . The results show that the distribution of MTs and the total amount of polymerized tubulin (MTs) in the spindle change during mitosis, suggesting the assembly and disassembly of MTs as well as the dislocation of MTs during mitosis .Since the pioneering work of Runnstrom (26) and Schmidt (31,32), the mitotic figures of many kinds of living cells have been known to be birefringent. Improvement of polarization microscope technique has made it possible to measure the variation of birefringence retardation within the mitotic apparatus (MA) and its change during mitosis (34,35) . Inoue (13) found that the mitotic spindle consists of many birefringent fibers by polarization microscopy . Development of electron microscopy has revealed that a number of microtubules (MTs) are oriented in the pole-to-pole direction in the spindle and in radial direction in the aster, so that it has been generally assumed that the spindle fibers and astral rays observed by light microscopy consist of MTs . Sato et al . (30) demonstrated that the birefringence of the spindle isolated from the sea-star oocyte

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Die Veränderungen der Plasmakolloide bei der Entwicklungserregung des Seeigeleies

Cited by 104 publications

References 56 publications

The Ultrastructure of the Nerve Axon Sheath

The Ultrastructure of the Nerve Axon Sheath

Significance of the Cell Membrane in Embryonic Processes

Quantitative studies on the polarization optical properties of living cells II. The role of microtubules in birefringence of the spindle of the sea urchin egg.

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