Basic proteins of mouse ova and blastocysts

Zusammenfassung Mit einer speziellen Färbetechnik auf basische Proteine wird gezeigt, dass die Intensität und damit auch die Quantität der basischen Proteine beim übergang vom 4-Zell-Stadium zum 8-Zell-Stadium im Cytoplasma stark zunimmt. Daraus wird der Schluss gezogen, dass erst zu diesem Zeitpunkt die genetische Information für die Proteinsynthese wirksam wird.     

In vitro fertilization of mouse and hamster eggs after freezing and thawing

Summary Mouse eggs (12–14%) and hamster eggs (87–94%) appear normal upon thawing after having been stored for 30 min to 25 h at –70°C and –196°C. While 89–98% of the normal appearing hamster eggs are capable of fertilization in vitro, only 4–13% of the mouse eggs can be fertilized. The ability of fertilized eggs to develop in culture and their viability upon transfer to pseudopregnant recipients is under investigation.This work was supported by grants from the U.S. Public Health Service and the Ford Foundation. Sincere thanks are due to Prof.Y. Nishikawa of Kyoto University, Japan, for advice and to Mrs.Rose Bartke and Ms.D. M. Hunt for assistance.     

Effect of diethylstilbestrol on glucose absorption by rat small intestine in vitro

Resumen El dietilestilbestrol inhibe la absorción activa de glucosa en el intestino de rata in vitro, aunque no impide la entrada del azucar en las células de la mucosa. La difusión pasiva de arabinosa y xilosa es facilitada por la droga.     

Effect of Ketamine hydrochloride on oxygen and glucose uptake by brain tissue in vitro

Resumen El clorhidrato de Ketamina (1×10^–3 M y 1×10^–4 M) incrementa el consumo de oxigeno de cortes de cerebro de rata incubados en Krebs-Ringer fosfato conteniendo 5 mM ó 100 mM de potasio. La droga no modifica el consumo de oxigeno de homogeneizado de cerebro total.     

Iproniazid (marsilid) reverses dopamine-effect and stimulates the growth of mouse neuroblastoma in vitro

Zusammenfassung Die hemmende Wirkung von Dopamin auf die Zellteilung von Neuroblastoma beruht wahrscheinlich nicht auf dem Effekt seines desaminierten Metaboliten, obwohl sie durch den MAO-Hemmer Marsilid aufgehoben wird.     

Effect of azimexon (BM 12.531) on mouse granulocyte-macrophage and monocyte-macrophage progenitor cells

Summary Treatment of mice with 25 mg/kg azimexon (BM 12.531) resulted in an increase in granulocyte-macrophage colony-forming cells (GM-CFC) in spleen and bone marrow after a transient depression in the cell populations. Bone marrow monocyte-macrophage colony-forming cells (MM-CFC) increased at 7 days after treatment, and splenic MM-CFC were least affected by azimexon treatment. The increase in granulocytic and monocytic colony-forming cells may play a role in the previously reported protection by azimexon against radiation and drug-induced toxicity.Supported by the Armed Forces Radiobiology Research Institute, Defense Nuclear Agency, under Research Work Unit MJ 00026.     

Biological effects of trilostane in vitro on oocyte maturation and fertilization in the hamster

Summary The effects of the inhibition of steroidogenesis by trilostane on oocyte maturation were examined by studying spontaneous maturation and fertilization in vitro. 10^–6 M trilostane had no influence on the meiotic process, whether the oocytes were naked or not. At a concentration of 10^–6 M and 10^–7 M trilostane, low normal pronuclear formation and high polyspermy were found during in vitro fertilization. However, no retarded male pronuclear development could be detected in the trilostane-treated group. Thus, steroid producing activity within ova is apparently necessary to prevent multiple sperm penetration, but it has no effect on meiosis or the action of the so-called male pronucleus growth factor (MPGF).     

Biological effects of trilostane in vitro on oocyte maturation and fertilization in the hamster

The effects of the inhibition of steroidogenesis by trilostane on oocyte maturation were examined by studying spontaneous maturation and fertilization in vitro. 10(-6)M trilostane had no influence on the meiotic process, whether the oocytes were naked or not. At a concentration of 10(-6)M and 10(-7)M trilostane, low normal pronuclear formation and high polyspermy were found during in vitro fertilization. However, no retarded male pronuclear development could be detected in the trilostane-treated group. Thus, steroid producing activity within ova is apparently necessary to prevent multiple sperm penetration, but it has no effect on meiosis or the action of the so-called male pronucleus growth factor (MPGF).     

Elevated glucose levels influence in vitro hatching,attachment, trophoblast outgrowth and differentiation of the mouse blastocyst

Summary A glucose concentration of 3.5 mg/ml is optimal for in vitro embryo attachment and trophoblastic cell outgrowth. Raising the concentration above 3.5 mg/ml does not improve embryo culture and can at certain concentrations be detrimental to embryo development.     

Effect of heat-labile enterotoxin (LT) produced byEscherichia coli on in vitro cell proliferation

Summary Filtrates fromE. coli H10407 cultures, giving a positive response for heat-labile enterotoxin (LT) in the Y-1 cell test, show an inhibitory activity both on³H-thymidine uptake by Ehrlich ascites cells and on granulocytic-macrophagic precursors (CFU-C) in murine bone marrow.Acknowledgments. We gratefully acknowledge the expert technical assistance of L. Basso and A. Gerosa of Department of Pathology, Hospital of Desio.     

Effect of pretreatment with prednisolone on the phagocytic activity of mouse peritoneal macrophages in vitro

Summary The phagocytic activity on in vitro cultured mouse peritoneal macrophages derived from animals treated with 6-alpha-methyl-prednisolone was examined. The statistical evaluation of results showed an increase of phagocytic activity of macrophages derived from treated animals in comparison with controls.     

Effect of two insecticides, lindane and DDVP (dichlorvos) on mouse adrenal glands]

Poisoning of non-pregnant female mice by sublethal doses of Dichlorvos and gamma-BHC (Lindane) induces prominent adrenal alterations. A significant weight increase of the glands is observed while Norepinephrine and Epinephrine content is depleted after Dichlorvos intoxication.     

Effect of the calmodulin inhibitor R24571 (calmidazolium) on rat embryos cultured in vitro

Summary The possible effects of inhibition of the calcium-binding protein, calmodulin, on mammalian morphogenesis have been investigated by culturing rat embryos in vitro from 9 1/2 to 11 1/2 days of development in the presence of R24571 (calmidazolium), a specific inhibitor of calmoldulin. Embryos cultured in 10^–2 mM R24571 for 48 h show inhibited development and exhibit a range of morphogenetic abnormalities including assymetry and neural tube defects. Embryos exposed to R24571 for the first 24 h of a 48 h culture are more severely affected than embryos exposed to R24571 for the last 24 h.Acknowledgments. We wish to thank Mr C. Veltkamp and Mr B. lewis for their expert help with the scanning electron microscopy and photography.