Effect of hypophysectomy or hysterectomy on the luteal 20α-hydroxysteroid dehydrogenase in pregnant rats

Riassunto Sono stati studiati con metodi enzimoistochimici alcuni meccanismi che controllano la comparsa della 20-idrossi-steroide-deidrogenasi (20-HSD) in ratte gravide o pseudogravide dopo ipofisectomia o isterectomia. I risultati dimostrano che nel primo periodo della gravidanza e in pseudogravidanza, l'ipofisi è necessaria per mantenere i corpi lutei privi di attività 20-HSD.     

The benzilic acid rearrangement of 3α,17β-Diacetoxy-11-hydroxy-12-oxo-5β-androst-9(11)-ene

Zusammenfassung Die Bildung von 11-Carboxy-3, 11, 17-trihydroxy-13-C-nor-5-androstan 11a,17-Lakton aus 3, 17-Diacetoxy-11-hydroxy-12-oxo-5-⁹(11)-androsten wird beschrieben. Der Mechanismus und die Stereochemie dieser Umwandlung (Retro-Aldolkondensation und Benzilsäureumlagerung) wird diskutiert.     

The distribution of some enzymes involved in the steroidogenesis of hen's ovary

Riassunto È stata studiata con metodi istochimici la distribuzione della ⁵-3-idrossisteroide deidrogenasi ( ⁵-3-HSDH) e delle 17-idrossisteroide deidrogenasi (17-HSDH), DPN- e TPN-dipendenti, nell'ovario di gallina ovulante. Mentre la ⁵-3-HSDH è presente in tutti i tessuti a secrezione steroide dell'ovario, la 17-HSDH è localizzata solo nelle cellule della granulosa.     

Wirkung von 6β-Methoxy-9β,10α-pregna-4,6-dien-3,20-dion

Summary 6-Methoxy-9,10 -pregna-4,6-diene-3,20-dione inhibites the ⁴-3-oxosteroid-5-reduction in microsomes and the ⁴-3-oxosteroid-5-reduction in the soluble fraction of male rat liver. The 3- and 3-hydroxysteroid dehydrogenase are not inhibited by this substance.

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Diese Arbeit wurde von der Firma Hoffmann-La Roche, Basel, unterstützt.     

Zur Synthese des Batrachotoxinins: Synthese von 3β-Acetoxy-16β, 20β-dihydroxy-4′-methyl-18-nor-5β, 14β-pregnano[13,14-f]hexahydro-1′,4'-oxazepin-3′-on(20a)

Summary The synthesis of 3-acetoxy-16, 20-dihydroxy-4-methyl-18-nor-5, 14-pregnano[13,14-f]hexahydro-1, 4-oxazepin-3-one (20a) is described.     

G-protein signaling: back to the future

Heterotrimeric G-proteins are intracellular partners of G-protein-coupled receptors (GPCRs). GPCRs act on inactive G·GDP/G heterotrimers to promote GDP release and GTP binding, resulting in liberation of G from G. G·GTP and G target effectors including adenylyl cyclases, phospholipases and ion channels. Signaling is terminated by intrinsic GTPase activity of G and heterotrimer reformation – a cycle accelerated by regulators of G-protein signaling (RGS proteins). Recent studies have identified several unconventional G-protein signaling pathways that diverge from this standard model. Whereas phospholipase C (PLC) is activated by G_q and G, novel PLC isoforms are regulated by both heterotrimeric and Ras-superfamily G-proteins. An Arabidopsis protein has been discovered containing both GPCR and RGS domains within the same protein. Most surprisingly, a receptor-independent G nucleotide cycle that regulates cell division has been delineated in both Caenorhabditis elegans and Drosophila melanogaster. Here, we revisit classical heterotrimeric G-protein signaling and explore these new, non-canonical G-protein signaling pathways.Received 21 October 2004; received after revision 20 November 2004; accepted 30 November 2004     

Triterpenoid XIII. The constitution of barring-togenol D

Zusammenfassung Die Struktur des aus der Frucht vonBarringtonia acutangula Gaertn. isolierten neuen Triterpenoiden, Barringtogenol D, ist als 3:22oxy-16:22-Oxido-olean-12-en ermittelt worden.     

Die Carbohydrasen der SpinnmilbeTetranychus urticae Koch (Acari,Tromb{ie307-1}diformes,Tetranychidae)diformes,Tetranychidae)

Summary In preparations of crushed whole spider mites (Tetranychus urticae Koch), the enzymes capable of hydrolyzing carbohydrates were identified. The products of the enzymic hydrolysis were detected by paper chromatography. The following substrates were hydrolyzed: Starch, maltose, sucrose, trehalose, melibiose, lactose, melezitose and raffinose. Not attacked were: Cellobiose, cellulose, pectin and pectic acid. In the homogenates there must be present an amylase, an -glucosidase, a -h-fructosidase, an - and -galactosidase. There is no indication for the presence of a -glucosidase, a cellulase, a pectinase and polygalacturonase.     

Histochemistry of ovarian 20α-hydroxysteroid dehydrogenase in the rat during the estrus cycle

Riassunto In ovaie di ratta, durante le fasi del ciclo estrale, fu determinata istochimicamente l'attività 3-HSD e 20-HSD. L'attività 20-HSD risulta localizzata esclusivamente nei corpi lutei. Essa compare nei giovani corpi lutei durante il proestro e si mantiene fino alla completa involuzione dell'organulo.     

Comparative analysis of human milk and human blood plasma by means of diffusion-in-gel methods

Zusammenfassung Mit Hilfe von Immunoelektrophorese und Doppeldiffusiontechnik wurden in Humanmilch an Blutplasmaproteinen serologisch identifiziert: Praealbumin, Albumin, Acid Seromucoid, ₁-Glykoprotein (3·5 S), Coeruloplasmin, Haptoglobin, ₂- oder-Lipoprotein, Transferrin, Fibrinogen, _2A-Globulin, _2M-Globulin und-Globulin.     

Inhibition of lung carcinoma cell growth by high density lipoprotein-associated α-tocopheryl-succinate

-Tocopheryl-succinate (TS) is a synthetic, anti-neoplastic derivative of -tocopherol. Here we studied the effects of free and high-density lipoprotein subclass 3 (HDL₃)-associated TS on the growth of human (A549) and mouse Lewis (LL2) lung carcinoma cells. Both free and HDL3-associated TS inhibited A549 growth in a time- and concentration-dependent manner. Treatment of A549 cells with TS-enriched HDL3 led to DNA fragmentation and a time-dependent decrease in immunoreactivity of poly(ADP-ribose)polymerase. Uptake experiments revealed a high capacity for selective TS uptake in excess of holoparticle endocytosis. Overexpression of scavenger receptor class B, type I (SR-BI), the prime receptor mediating selective lipid uptake, in A549 cells resulted in significantly increased selective TS uptake, a finding associated with complete cellular growth arrest. The present in vitro findings were verified in an in vivo model: tumor inoculation in C57BL6 was performed with either wild-type, -galactosidase- or SR-BI-overexpressing LL2 cells. After tumor inoculation, the animals received six consecutive intravenous injections of TS. This experimental setup resulted in significantly reduced tumor burden in animals that were inoculated with SR-BI-overexpressing LL2 cells but not in animals inoculated with wild-type or -galactocidase-transfected cells. Based on our in vitro and in vivo findings, we propose that SR-BI could provide a novel route for HDL₃-mediated drug delivery of anti-neoplastic drugs.Received 8 March 2004; received after revision 7 April 2004; accepted 26 April 2004     

Histochemistry of ovarian 20α-hydroxysteroid dehydrogenase in mature hypophysectomized rats

Riassunto È stato studiato il quadro enzimatico dei corpi lutei (C.L.) di recente formazione nelle ovaie di ratte ipofisectomizzate. In particolare si è constatato come la comparsa dell'attività 20-idrossisteroide deidrogenasica non sia impedita dall'ipofisectomia. Si suggerisce la possibilità che l'ipofisi eserciti una azione inhibitrice sulla comparsa di questo enzima.     

Exchange of tritium from randomly tritiated taurocholate by microbial bile salt oxidoreductases

Summary Tritium distribution on randomly labelled taurocholate (TC) was estimated at 28%, 4%, 1% and <0.5% on the hydrogens opposite the 3-, 7- and 12-OH groups and taurine moiety respectively. Anomalously,C. perfringens 3-hydroxysteroid dehydrogenase (3-HSDH) catalyzed tritium loss of 36% on formation of 7-, 12-dihydroxy-3-keto-5-cholanoate, implying additional losses of tritium at other sites by this enzyme.This work is supported by the National Cancer Institute.     

Hemmung der Phosphodiesterase aus Rattenherzen durch Intensain

Summary Intensain causes in vitro a significant and apparently competitive inhibition of phosphodiesterase, which transforms the 3,5-AMP to 5-AMP. These results explain some intensain effects, especially the period of latency to reach the maximum effect, the inotropic action and its reaction under the influence of-blocking and-stimulating agents^10–13.

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3-(-Diäthylamino-äthyl)-4-methyl-7-carbäthoxy-methoxy-2-oxo-(1,2-chromen), Carbochromen.     

Metabolism in Porifera. IX. Studies on the biological conversion of cholesterol into 19-nor-cholestanol by the spongeAxinella polypoides

Summary The conversion of cholesterol into 19-nor-5-cholestan-3-ol by the spongeAxinella polypoides involves a partial loss (40%) of the 3-hydrogen atom; moreover administration to the sponge of [4-¹⁴C]cholesterol tritiated at C-4 and C-7 showed that the 4- and 7-hydrogen atoms are retained in this conversion. A competitive uptake experiment, [4-¹⁴C]cholesterol vs. [7-³H₂]5-cholestanol, showed that the sponge utilized exclusively cholesterol for the production of 19-nor-5-cholestan-3-ol.Part of this work has been presented at the Nato Conference on Marine Natural Products (Jersey, Great Britain, October, 1976).-This contribution is part of the Programma finalizzato Oceanografia e Fondi marini-sottoprogetto Risorse biologiche C.N.R. Italy.     

α-aminooxy-acid derivatives with potent antituberculotic effect

Zusammenfassung Es wurde festgestellt, dass einzelne -Aminooxy-carbonsäure-Derivate, d.h.-AOA-Amide,-AOA-Hydrazide und-AOA-Hydroxamsäure, in vitro und auch in vivo eine ausgeprägte Hemmung auf verschiedeneM. tuberculosis-Stämme aufweisen.     

An epoxidation byCorynebacterium simplex

Zusammenfassung Während unserer Untersuchungen über die mikrobiologische Dehydrierung verschiedener 16-Methylsteroide durch Bakterienkulturen vonCorynebacterium simplex, wurde eine neue Art von Umwandlung beobachtet. Von 16-Methyl-9(11)-pregnen-17, 21-diol-3, 20-dion-21-acetat ausgehend, gelang es aus den Kulturfiltraten 16-Methyl-1, 4-pregnadien-9, 11-epoxy-17, 21-diol-3, 20-dion zu isolieren. In einigen Fällen wurde auch das4-Derivat dieser Verbindung als Nebenprodukt erhalten.     

The molecular structure of the benzilic acid rearrangement product of 3α, 17β-diacetoxy-11-hydroxy-12-oxo-5β-androst-9(11)-ene

Zusammenfassung Die Struktur desp-Brombenzoates des Benzilsäureumlagerungsproduktes von 3, 17-Diacetoxy-11-hydroxy-12-oxo-5-9(11)-androsten wurde durch dreidimensionale Röntgenstrukturanalyse eines Einkristalls als 3-p-Brombenzoat des 11-Carboxy-3, 11, 17-trihydroxy-13-C-nor-5-androstan 11a, 17-Laktons erkannt.