Roussel Uclaf

About: Roussel Uclaf is a based out in . It is known for research contribution in the topics: Alkyl & Alkoxy group. The organization has 1888 authors who have published 2338 publications receiving 36508 citations.

Kappa Agonists and Vasopressin Secretion

Abstract: The effects of opiates on vasopressin secretion have been controversial for many years. This is probably due to the existence of different types of opioid receptors and to the lack of specificity of the compounds used. Specific kappa agonists, which have been described recently, produce a marked diuretic effect without any associated increase in electrolyte elimination. They seem to exert their effects through an interaction with kappa receptors situated on nerve terminals and/or pituicytes. These receptors could be directly coupled to L-type calcium channels, their activation leading to a decrease in the effectiveness of action potentials to evoke vasopressin secretion from nerve terminals in the neurohypophysis. This mechanism of action may explain the decrease in plasma vasopressin levels induced by kappa agonists.

Preparation and Characterization of Fluorinated Fullerenes

Abstract: Fluorination of pure C60 and a C60/C70 mixture has been studied under different experimental conditions: reaction time, temperature, fluorine pressure. The products obtained have been characterized by IR and NMR spectroscopy, X-ray diffraction, and mass spectrometry analysis by positive and negative ions.

Atomic Chirality, a Quantitative Measure of the Chirality of the Environment of an Atom

Abstract: In this article we propose a measure of chirality, more particularly of the chirality of an atom's environment in a molecule. The environment is defined both by the geometry of the closest atoms an...

Toxicological Study on RU 486

Abstract: RU 486 showed no toxic effects after acute oral administration to mice and rats. Six-month toxicological studies were performed, using rats (15, 25, and 125 mg/kg) and cynomolgus monkeys (5, 15, and 45 mg/kg). Most of the modifications induced by the high doses are due to antihormonal properties of the compound such as: antiprogesterone activity in females (frequent estrus and mammary-gland development in rats, suppression of menstruation and a decrease in serum progesterone in monkeys); antiglucocorticoid activity (increase in kidney and adrenal weights, and, in monkeys, increase in serum ACTH and cortisol); and antiandrogenic activity in male rats (decrease in prostate and seminal vesicle weights). RU 486 showed no mutagenic effect either in vitro or in vivo and provoked no teratogenic effect at usable doses, that is to say non-abortive doses (0.5 mg/kg in rats and 1 mg/kg in rabbits). Studies were performed on albino mice (Swiss — SPF) and albino rats (Sprague-Dawley — SPF), on cynomolgus monkeys (Macaca fascicularis) and on rabbits (HY). RU 486 was administered orally suspended in water containing 0.25 to 1% of carboxymethylcellulose with or without polysorbate 80 (0.20%).

Properties of Biospecific Adsorbents, Obtained by Immobilization of Oestradiol 7α‐Derivatives, for Purification of Calf‐Uterine Cytosol Oestradiol Receptor

Abstract: The properties of three types of adsorbents obtained by coupling oestradiol 7 alpha-derivatives to agarose were compared. The adsorbents examined were: oestradiol 7 alpha-decamethylene-agarose, oestradiol 7 alpha-decamethylene-poly(anayl-lysine)-agarose and oestradiol 7 alpha-trimethylene-poly(alanyl-lysine)-agarose. The following results were obtained. (1) All these adsorbents are stable at 0 degrees C for a least a year when stored in water. In the presence of cytosol they are stable for several hours and are reusable after a simple wash. (2) A new method allowing the calculation of the maximala receptor binding capacity of an absorbent was developed. (3) The geometry of the column and the dynamics of the loading have no influence on the binding capacity of the adsorbents. (4) Binding of the cytosol receptor to the adsorbent depends on whether the receptor had previously been partially purified by heparin-Ultrogel chromatography or treated with low or high salt concentration or trypsin. It was demonstrated that aggregation decreases the binding of the receptor to the adsorbents. (5) A satisfactory recovery of receptor upon elution is possible only with biospecific adsorbents containing low concentrations of coupled steroid (less than or equal to 0.2 mg/ml). The use of these adsorbents for the purification of the trypsin-treated receptor directly from cytosol allowed a 2500-fold purification corresponding to 5% pure protein (assuming one oestradiol binding site per molecule of Mr 60000). When starting from a low salt preparation containing the native 8-S receptor, partially purified by heparin-Ultrogel chromatography, preliminary experiments using affinity chromatography gave a further purification of 250--500-fold and led to a 50--90% pure protein (assuming one oestradiol binding site per molecule of Mr 70000).