Vinblastine Sulfate for Injection

1970 ◽

Vol 28 ◽

pp. 186-187

Author(s):

Krishan Awtar

Keyword(s):

Cell Division ◽

Normal Cell ◽

Virus Production ◽

Multinucleate Cells ◽

Daughter Cells ◽

Cell Divisions ◽

Nuclear Membranes ◽

Division 2 ◽

Vinblastine Sulfate

Exposure of cells to low sublethal but mitosis-arresting doses of vinblastine sulfate (Velban) results in the initial arrest of cells in mitosis followed by their subsequent return to an “interphase“-like stage. A large number of these cells reform their nuclear membranes and form large multimicronucleated cells, some containing as many as 25 or more micronuclei (1). Formation of large multinucleate cells is also caused by cytochalasin, by causing the fusion of daughter cells at the end of an otherwise .normal cell division (2). By the repetition of this process through subsequent cell divisions, large cells with 6 or more nuclei are formed.

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Linear Arrays of Helical Polyribosomes in Cells Exposed to Antitumor Drug Vincristine Sulfate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063706 ◽

1969 ◽

Vol 27 ◽

pp. 358-359

Author(s):

Awtar Krishan

Keyword(s):

Close Association ◽

Annulate Lamellae ◽

Large Array ◽

Vincristine Sulfate ◽

Linear Arrays ◽

Golgi Membranes ◽

Related Drug ◽

Drug Leads ◽

Lethal Doses ◽

Vinblastine Sulfate

Earle's L-929 fibroblasts treated with mitosis-arresting but sub-lethal doses of vinblastine sulfate (VLB) show hypertrophy of the granular endoplasmic reticulum and annulate lamellae. Exposure of the cells to heavier doses of vincristine sulfate (VCR), a VLB-related drug, leads to the accumulation of large amounts of helical polyribosomes, Golgi membranes and crystals in the cytoplasm. In many of these cells a large number of helical polyribosomes are arranged in prominent linear rows, some of which may be up to 5 micrometers in length. Figure 1 shows a large array of helical polyribosomes near a crystalline mass (CRS) in an Earle's L-929 fibroblast exposed to VCR (5ϒ/ml.) for 3 hours At a higher magnification, as seen in figure 2, the helical polyribosomes are seen arranged in parallel rows. In favorably cut sections, a prominent backbone like "stalk" of finely granular material, measuring approximately 300Å in width is seen in close association with the linear rows of helical polyribosomes.

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SYNTHESIS AND STORAGE OF MICROTUBULE PROTEINS BY SEA URCHIN EMBRYOS

The Journal of Cell Biology ◽

10.1083/jcb.50.2.516 ◽

1971 ◽

Vol 50 (2) ◽

pp. 516-528 ◽

Cited By ~ 83

Author(s):

Rudolf A. Raff ◽

Gerald Greenhouse ◽

Kenneth W. Gross ◽

Paul R. Gross

Keyword(s):

Amino Acids ◽

Sea Urchin ◽

Messenger Rna ◽

Binding Activity ◽

Total Soluble Protein ◽

Cell Stage ◽

Lytechinus Pictus ◽

Sea Urchin Embryos ◽

Tritiated Amino Acids ◽

Vinblastine Sulfate

Studies employing colchicine binding, precipitation with vinblastine sulfate, and acrylamide gel electrophoresis confirm earlier proposals that Arbacia punctulata and Lytechinus pictus eggs and embryos contain a store of microtubule proteins. Treatment of 150,000 g supernatants from sea urchin homogenates with vinblastine sulfate precipitates about 5% of the total soluble protein, and 75% of the colchicine-binding activity. Electrophoretic examination of the precipitate reveals two very prominent bands. These have migration rates identical to those of the A and B microtubule proteins of cilia. These proteins can be made radioactive at the 16 cell stage and at hatching by pulse labeling with tritiated amino acids. By labeling for 1 hr with leucine-3H in early cleavage, then culturing embryos in the presence of unlabeled leucine, removal of newly synthesized microtubule proteins from the soluble pool can be demonstrated. Incorporation of labeled amino acids into microtubule proteins is not affected by culturing embryos continuously in 20 µg/ml of actinomycin D. Microtubule proteins appear, therefore, to be synthesized on "maternal" messenger RNA. This provides the first protein encoded by stored or "masked" mRNA in sea urchin embryos to be identified.

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