Der Einfluss einiger C21-Steroide auf die Wassereinlagerung in wachsenden embryonalen Knorpeln in vitro

Summary Embryonic chick cartilages were cultivated in a synthetic nutrient medium. In this experimental procedure cortisol is known to reduce the water uptake of the cartilages. It was found that some C₂₁-steroids exert a similar activity. Those of the steroids investigated, which inhibit water uptake, have in common a ⁴-3-keto group, an 11-hydroxy group, and a keto group in position 20; oxygen functions in positions 21 and 17 seem to be of minor importance for this activity. The possibility of these steroids being inactivated by cellular enzymes is discussed.     

Phosphoglycerate mutase isozymes in the lower vertebrates

Summary The phosphoglycerate mutase isozyme patterns from cyclostomata, cartilaginous and bony fish were analyzed. The observed patterns indicate that a duplication of a single ancestral gene coding for phosphoglycerate mutase took place during the evolution of the gnathostome vertebrates.     

Rat mammary cancer inhibition by a prolactin suppressor, 2-bromo-α-ergokryptine (CB 154)

Zusammenfassung 2-Br--Ergokryptin (=CB 154) wurde täglich während 80–100 Tagen, beginnend mit der Carcinogenapplikation, DMBA - (5 mg i.v.)-behandelten weiblichen Ratten in der Dosis 6 mg/kg i.p. verabreicht. CB 154 bewirkte ein verzögertes Erscheinen und ein langsameres Wachsen der Mamma-Tumoren sowie eine verminderte Todesrate der carcinogenbehandelten Ratten.     

The history of cyclosporin A (Sandimmune®) revisited: Another point of view

The immunosuppressant cyclosporin A (Sandimmune^®) has become the first line treatment for preventing rejection of transplanted organs and for certain, autoimmune diseases. The discovery of that drug and its preclinical development are described, and it is shown that most earlier accounts of the history of this compound are, in important respects, incorrect and misleading.     

Die Wirkung von Progesteron und Progesteronmetaboliten auf das Wachstum von embryonalem Knorpel in vitro

Summary Embryonic chick bones were cultured in vitro in the presence of progesterone and of a series of progesterone metabolites. It was found that only 5-pregnane-3,20-dione, 3-hydroxy-5-pregnane-20-one, and ⁴-pregnene-20-ol-3-one influence the growth of bones in vitro in a manner similar to progesterone. All other investigated progesterone metabolites exert either a different or no demonstrable action on bone growth.     

Role of lysine side chains in metallothionein

Summary pK_a-Values of lysine residues of mammalian metallothionein were determined by chemical titration measurements of -CH₂ lysine resonances in the¹H-NMR spectra. They are about 0.5 pH-unit higher than the average pK_a-value of a metal-free derivative, suggesting interaction of the positively charged residues with the two three-fold negatively charged metal-thiolate clusters of the metal-containing form. Deprotonation of the lysines leads to circular dichroism changes attributable to an electrostatically induced structural transition of the protein.To whom correspondence concerning this paper should be addressed.     

Protection of rat gastric mucosa against ethanol injury by the new synthetic prostaglandin MDL 646

Summary Oral administration to fasted rats of absolute ethanol produces extensive necrotic lesions of gastric mucosa as well as a massive leakage of proteins and mucus glycoproteins into gastric lumen. When the new synthetic prostaglandin MDL 646, belonging to the PGE₁ series, is administered intragastrically (2 or 10 g/kg) 30 min before ethanol administration, a significant protection of rat gastric mucosa against alcohol injury is observed.This work was supported in part by a contribution from Ministero della Pubblica Istruzione (MPI), Rome, Italy.