Die Reversibilität der Wirkung von Digitoxin,Strophanthidin und Strophanthidin-3-bromazetat am Papillarmuskel und einer mikrosomalen Na+-K+-aktivierbaren ATPase des Meerschweinchens

Summary The reversibility of the inhibitory action of strophanthidin, strophanthidin-3-bromoacetate, and digitoxin on the Na⁺-K⁺-ATPase activity (microsomal fraction, guinea-pig brain) was compared with the rate of decline of their positive inotropic effects (papillary muscle, guinea-pig heart) after exposure to drug-free solution. The actions of strophanthidin and digitoxin were easily reduced on both systems. Strophanthidin-3-bromoacetate, however, was found to have an irreversible blocking effect on the transport ATPase, whereas its inotropic action could be rapidly abolished.

---

---

Teilergebnisse der Dissertation von U.Fricke, Mainz.     

Spectral efficiency as function of latency in the visual mechanism of insect (Tenebrio molitor L.)

Zusammenfassung Bei Untersuchungen der elektrophysiologischen Reaktion des Facettenauges beim MehlkäferTenebrio molitor wurde die Maximalreaktion zwischen 510 und 530 nm gefunden. Latenz und Amplitude dienten als Kriterien der facettären Spektraleffizienz.     

Failure of amantadine to modify serum growth hormone and insulin levels

Riassunto In sei volontari normali, la somministrazione acuta, sia orale che e.v. di 300 mg di amantadina non ha causato modificazioni dei livelli serici di GH. Anche i valori di insulinemia, glicemia e di FFA plasmatici non hanno subito variazioni.     

Autoradiographic studies with S35 on the development of the rat embryo

Zusammenfassung Es wurde die S³⁵-Fixation bei Embryonen von etwa 30 graviden Ratten untersucht. Bindegewebe, Knorpel und gewisse rasch wachsende Gewebe wiesen hohe Sulphataufnahmen auf, vermutlich auf Grund des Einbaues von radioaktivem Schwefel in die Sulfomukopolysachariden.     

Changes in photoelectron transport of chloroplasts isolated from dark stressed leaves of maize seedlings

Summary Transfer of light-grown maize seedlings to dark causes a loss in the contents of chlorophyll, protein and RNA of leaves, and a decline in DCPIP photoreduction by isolated chloroplasts. The loss in DCPIP-Hill reaction is attributed to the dark stress-induced damage of O₂ evolving system of thylakoid membranes.Acknowledgment. We thank Prof. M.C. Dash, School of Life Sciences, for encouragement and providing the facilities.