Silymarin, an inhibitor of prostaglandin synthetase.

Silybin (I), silydianin (II) and silychristin (III), the main constituents of silymarin, inhibit the formation of prostaglandins in vitro. The inhibition is log-linearly dependent on the concentration of the effectors.     

Silymarin,an inhibitor of lipoxygenase

Summary Silybin (I), silydianin (II) and, silychristin (III), the main constituents, of silymarin, non-competitively inhibit the lipoxygenase from soybeans (EC 1.13.11.12) in vitro.F. Fiebrich, Thesis, University of Vienna 1977.H. Koch, Dt. ApothZtg118, 1844 (1978); reported in part at the Colloquium Pharmaceuticum in Münster, 21 st November 1978.     

Silymarin, an inhibitor of lipoxygenase.

Silybin (I), silydianin (II) and silychristin (III), the constituents of silymarin, non-competitively inhibit the lipoxygenase from soybeans (EC 1.13.11.12) in vitro.     

Calcium dobesilate (Doxium) as a prostaglandin synthetase inhibitor in pregnant human myometrium in vitro

This comparative study on the effect of calcium dobesilate and indomethacin on prostaglandin biosynthesis was performed on microsomal fractions of pregnant human myometrium. Both drugs inhibited prostaglandin synthesis, indomethacin being more potent. Calcium dobesilate inhibited, in a dose-dependent manner, the synthesis of 6-oxo-PGF1 alpha, PGF2 alpha, PGE2 and TXB2. Its inhibitory action is comparable to that of etamsylate.     

Calcium dobesilate (Doxium) as a prostaglandin synthetase inhibitor in pregnant human myometrium in vitro

Summary This comparative study on the effect of calcium dobesilate and indomethacin on prostaglandin biosynthesis was performed on microsomal fractions of pregnant human myometrium. Both drugs inhibited prostaglandin synthesis, indomethacin being more potent. Calcium dobesilate inhibited, in a dose-dependent manner, the synthesis of 6-oxo-PGF₁, PGF₂, PGE₂ and TXB₂. Its inhibitory action is comparable to that of etamsylate.     

Inhibition of prostaglandin synthetase by psychotropic drugs

Zusammenfassung Psychopharmaka mit neuroleptischer, antidepressiver und/oder tranquillisierender Wirkung, die eine trizyklische Struktur besitzen, hemmen in vitro dosisabhängig die Prostaglandin-Synthetase, welche aus Ochsensamenblase isoliert wurde. Hingegen weist das Neuroleptikum Haloperidol, das sich strukturell von den anderen untersuchten Präparaten wesentlich unterscheidet, kaum einen solchen Effekt auf. Die pharmakologische Bedeutung dieser Befunde wird diskutiert.     

Effect of carbenoxolone on phosphodiesterase and prostaglandin synthetase activities

Summary Carbenoxolone inhibited in vitro cAMP and cGMP phosphodiesterases in a concentration-dependent and noncompetitive manner. Prostaglandin synthetase activity of rabbit kidney medulla was slightly stimulated by carbenoxolone 0.1–0.5 mM, but inhibited by higher concentrations.Acknowledgment. Supported by a grant from the Orion and Medica Scientific Foundation, Finland.     

Effect of carbenoxolone on phosphodiesterase and prostaglandin synthetase activities.

Carbenoxolone inhibited in vitro cAMP and cGMP phosphodiesterases in a concentration-dependent and noncompetitive manner. Prostaglandin synthetase activity of rabbit kidney medulla was slightly stimulated by carbenoxolone 0.1--0.5 mM, but inhibited by higher concentrations.     

Physiologische und ultrastrukturelle Testung der neuen Substanz Silymarin an den Vorderhornganglienzellen des Kaninchens

Summary The effect of Silymarin on the function and structure of lumbar anterior horn cells in the rabbit was studied under graduated ischemia. It was shown that Silymarin has neither useful nor injurious influence on the anterior horn cells examined.     

Glutamine synthetase,an enzyme characteristic of vertebrate systems in invertebrate tissues

Zusammenfassung Nachweis eines Invertebraten-Enzyms, das bei Vertebraten insbesondere im Nervengewebe eine wichtige Rolle spielt. Diese Glutamin-Synthetase wurde vor allem im optischen Ganglion in der Retina und im Gehirn zweier Tintenfischarten gefunden und überdies in sehr geringer Menge bei Crustaceen und Echinodermen.

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We wish to acknowledge the support of NSF Grant No. GE-19211 to J.E.M. during this study.     

Morphine as inhibitor of prostaglandin E1 in the isolated guinea-pig intestine

Zusammenfassung Es wird gezeigt, dass Analgetika vom Morphintypus die am isolierten Meerschweinchen-dünndarm nach Zugabe von Prostaglandin E₁ erfolgenden Kontraktionen ähnlich wie die durch Arachidonsäure (-peroxid) erzeugten Kontraktionen in spezifischer Weise zu antagonisieren vermögen.     

Sodium azide,an efficient inhibitor of protein diazotization

Résumé L'azide de sodium est un inhibiteur très efficace de la réaction de diazotation. Il réagit avec l'ion de diazonium à des molarités approximativement égales.     

Etamsylate as inhibitor of prostaglandin biosynthesis in pregnant human myometrium in vitro

Summary The effects of etamsylate on prostaglandin (PG) biosynthesis in microsomes of pregnant human myometrium in vitro have been determined, and compared with those of indomethacin. Both drugs inhibited PG biosynthesis, indomethacin being the more potent inhibitor of the two. Etamsylate inhibited synthesis of 6-oxo-PGF₁, PGF₂, PGE₂, and thromboxane B₂; increasing the concentration of etamsylate increased the inhibition of synthesis. It is suggested that etamsylate has no anti-cyclo-oxygenase activity, but acts by inhibiting the activity of prostacyclin synthetase, endoperoxide reductase, endoperoxide isomerase, and thromboxane synthetase.     

Ketoconazole,an inhibitor of calcium transport in skeletal muscle sarcoplasmic reticulum

Summary Ketoconazole, an antimycotic agent, inhibits calcium binding and accumulation, and induces calcium release in sarcoplasmic reticulum. The Mg²⁺-ATPase and the (Ca²⁺+Mg²⁺)-ATPase activities are stimulated at low but inhibited at high concentrations of ketoconazole.The author wishes to thank Dr K. S. Cheah for discussion and Mr C. C. Ketteridge for preparing the sarcoplasmic reticulum and carrying out the ATPase assays.