Cytochalasin D is able to mimic the effects of phalloidin on the rat liver

Summary Cytochalasin D induces a strong potassium release in the isolated perfused rat liver and leads to vacuolization of the liver parenchymal cells. These effects are similar to the action of phalloidin on the rat liver. Since phalloidin and cytochalasin act in a different way on microfilaments, it is suggested that any disturbance of the function of microfilaments can induce these effects.Acknowledgment. I thank Professor Th. Wieland for his interest in this investigation. The technical assistance of Iris Gilbert is very much appreciated.     

Morphological effects of estrogen on the female rat liver nucleolus

Summary Prolonged administration of nonphysiological amounts of estrogen induced markedly enlarged nucleoli volumes in rat hepatocytes, indicative of increased nucleolar RNA synthesis. Physiological amounts of drug had no apparent morphological effects on the hepatocytes.I thank Dr L. Biempica, Department of Pathology, Albert Einstein College of Medicine, for the electron microscopy studies.     

The effects of actinomycin D and chloramphenicol on the rat preimplantation embryos

Summary Actinomycin D and chloramphenicol, injected in the rat on day 3 or 4 of gestation, induce embryolethality and embryotoxicity. These effects are revealed on day 5 of pregnancy by reduced number of blastocysts and by decrease of mean blastomeres number.     

The effects of actinomycin D and chloramphenicol on the rat preimplantation embryos

Actinomycin D and chloramphenicol, injected in the rat on day 3 or 4 of gestation, induce embryolethality and embryotoxicity. These effects are revealed on day 5 of pregnancy by reduced number of blastocysts and by decrease of mean blastomeres number.     

The effects of 4 detergents on the respiration of mitochondria isolated from rat liver]

The effects of these four detergents (two non-ionic: Titron X100 and Tween 80, two ionic: sodium cholate and sodium dedeoxycholate) upon the respiratory intensities of mitochondria and upon the ADP/0 and respiratory control ratios were observed. At low concentrations and in the absence of exogenous ADP, non ionic as well as ionic detergents provoked a threefold (or fourfold) increase of the respiratory intensities of mitochondria. At higher concentrations, the four detergents were inhibitory for mitochondrial oxidations in the order: Triton X 100 greater than DOC greater than cholate greater than Tween 80. At increasing doses, the four detergents progressively decreased the phosphorylating capacities of mitochondria.     

Glucocorticoid and mineralocorticoid effects in rat liver and kidney

Zusammenfassung Die biochemischen Wirkungen von Aldosteron in der Rattenniere und Corticosteron in der Rattenleber wurden untersucht und der Mechanismus der Hormonwirkung diskutiert.     

Lymphocytes, but not cancer cells are able to penetrate into the rat embryo yolk sac wall

Normal rat lymphocytes and cells of 2 highly invasive tumors, the L5222 rat leukemia and the VW rabbit carcinoma, were inoculated in vitro on the mesothelial surface of the visceral wall of the rat embryo yolk sac. After 48 h, lymphocytes, without any damage being inflicted on the mesothelial cells, had penetrated deeply into the yolk sac wall, whereas both kinds of cancer cells had destroyed the mesothelial cells, but not advanced beyond the basal lamina.     

Lymphocytes,but not cancer cells are able to penetrate into the rat embryo yolk sac wall

Summary Normal rat lymphocytes and cells of 2 highly invasive tumors, the L5222 rat leukemia and the V2 rabbit carcinoma, were inoculated in vitro on the mesothelial surface of the visceral wall of the rat embryo yolk sac. After 48 h, lymphocytes, without any damage being inflicted on the mesothelial cells, had penetrated deeply into the yolk sac wall, whereas both kinds of cancer cells had destroyed the mesothelial cells, but not advanced beyond the basal lamina.     

Does nitrogen mustard mimic the X-ray effects in any case?

Résumé Les effets de l'ypérite nitrée sur le cerveau et yeux de l'embryon du rat blanc ont été analysés. Seulement les embryons présentant un aspect normal ont été coupés et colorés. De larges centres de nécrose ont été trouvés sur les coupes tandis que les «rosettes» n'ont pas pu être décelées.Bien que connue comme radiomimétique, l'yperite nitrée ne mime pas les rayons X en ce qui concerne la formation des «rosettes» dans le cerveau.     

The effect of N′-Nitro-N-Nitroso-N-Methylguanidine on the liver after administration to the rat

Résumé La nitrosoguanidine administrée à des rats par sonde stomacale provoque la formation de très nombreux kystes biliaires dans le foie et, dans chaque cas, de tumeurs d'estomac squameuses.     

Thyroid hormones and cathepsin D activity in the rat liver,kidney and brain

Summary The effect of thyroidectomy and subsequent treatment with tri-iodothyronine (T₃), as well as that of thyrotoxicosis, was examined on cathepsin D activity in the rat liver, kidney and brain. Thyrotoxicosis resulted in a generalized increase in the enzyme activity in the 3 tissues; the effect of other thyroidal states was diverse and tissue-specific.     

Effect of adrenalectomy on the response of rat liver polyribosomes to whole-body gamma radiation

Résumé L'adrénalectomie supprime le net déplacement, causé par l'irradiation, vers les espéces de polyribosomes plus lourdes observées chez les rats normaux irradiés. Ces résults font supposer que l'action de l'irradiation sur les polyribosomes du foie est réglée au moins en partie, par la glande surrénale.

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Recipient of U.S. Public Health Service Research Career Development Award No. CA 38655 from the National Cancer Institute and on special leave from August 1969–July 1970 at the Département de Radiobiologie, Centre d'Etude de l'Energie Nucléaire, Mol (Belgium).