Die Augenstielbewegungen der Languste (Palinurus vulgaris)

Summary Palinurus vulgaris shows clear compensatory eye stalk movements when turning actively around a vertical axis. Exactly the same eye stalk movements are observed after blinding of the animal (measurement of film pictures). On passive rotation only the intact animal shows compensatory eye stalk movements (= optomotoric reactions); in the blinded lobster such movements are lacking, except when a torsion of the body with respect to the legs is effectuated (stimulation of proprioceptors). It is suggested that the compensatory eye stalk movements of the actively turningPalinurus are no optomotoric reactions, and possibly no sensory reactions at all; but that they are spontaneous acts originating primarily within the central nervous system.     

Aktivität der Aldolase und der Succinatdehydrogenase (SDH) in der weissen und roten Skelettmuskulatur junger und alter Ratten

Summary The activity of aldolase and succinatdehydrogenase (SDH) in white and red skeletal muscle of young (3–7 months) and old (20–30 months) rats has been determined. In addition also the SDH of liver was measured. The activity of aldolase is higher in white than in red muscles, while SDH shows a higher activity in red than in white muscles. The activity of aldolase is not influenced by ageing in white muscles, but decreased in red muscles by 23%. In old animals the activity of SDH is 34% less in white and 52% less in red muscles. In liver the activity is 44% less. The significance of these changes for the energy metabolism of skeletal muscle is discussed.     

Elektroretinogramm und Netzhautstruktur der Sumpfohreule (Asio flammeus)

Summary Single flash and flicker electroretinograms were recorded for a nocturnal owl and the results discussed in terms of its retinal structure. The differences both in electrical response and in retinal structure between the owl and the pigeon were less than those found between nocturnal and diurnal mammals.     

Zur Frage der Verteilung von Radiolutetium (177Lu) im Organismus der Maus bei unterschiedlicher Applikationsart

Summary The authors describe the absorption, distribution, and excretion of¹⁷⁷LuCl₃ following subcutaneous and intraperitoneal injection of 4 μC¹⁷⁷Lu in mice over a period of 30 days after injection. This isotope shows certain differences in its biological behaviour opposite to the light rare earthes such as lanthanum, cerium etc.      

Frühe Stadien der Erholung bei bestrahlten ratten und Mäusen

Summary A split dose experiment was performed in 12-, 24- or 32-day-old Wistar rats. About 4000 animals were used. The first dose given was 200 R whole-body X-irradiation in the 2 younger groups, and 260 R in the oldest group. At intervals from 6–48 h after the first, a second irradiation was given in order to estimate the LD50(30). No recovery was seen in terms of the LD50(30) differences between preirradiated and normal animals 6 h after the first dose. At the 12 h interval marked recovery was found in all 3 age groups, but less recovery was apparent at the later intervals.     

Form und Zellzahl der akustischen Nervenzentren in der Medulla oblongata von Eulen (Striges)

Summary The special form and the number of nerve cells of the auditory centres in the owl's medulla are described and compared with those of other birds. The highest degree of differentiation is found in the most nocturnal species,Tyto alba. Comparing the number of auditory nerve cells in the medulla with the weight of the brain in birds of different size, an unexpectedly low rate of increase was found.     

Zum Schlüpfprozess bei Fischen: II. Gewinnung und Charakterisierung des Schlüpfsekretes bei der Regenbogenforelle (Salmo gairdneri Rich.)

Summary A method is described to get the secrete of the hatching glands together with the perivitelline fluid by stimulating the eggs ofSalmo gairdneri with dissolved gaseous nitrogen in various buffers. Characterizing this fluid by various methods there could be shown some enzymes of those a proteinase alone seems to be the really hatching enzyme.Der Deutschen Forschungsgemeinschaft sei für finanzielle Unterstützung gedankt.     

Nachweis circanualer Periodik bei der Quappe (Lota lota L.) (Pisces,Gadidae)

Summary Investigations on daily rhythm in the burbot (Lota lota L.) in the Arctic Circle showed that a phase-shift in the locomotor activity occurred under nLD; the fish, which is night-active in the summer, phase-shifted 180 degrees in relation to the phase-timing factor. This phase-shift was also found in a fish kept in artificial light (LD 1212) which occurred at almost the same time of year. Accordingly an endogenous circaannual rhythm is suggested.

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Die Untersuchungen erfolgten mit Unterstützung der Max-Planck-Gesellschaft zur Förderung der Wissenschaften und des Staatlichen Schwedischen Naturwissenschaftlichen Forschungsrates.     

Die Lecithin/Lysolecithin- und Cholesterin/Cholesterinester-Beziehung im Rattenserum bei der Galaktosamin-Hepatose

Summary After single i.p. application of 300 mg/kgd-galactosamine-hydrochloride in male conventional Wistar-II-rats, the concentration of serum cholesterol esters and serum lysolecithin decreases in statistical significance, serum lecithin increases slightly. Because the relation of esterified serum cholesterol to total serum cholesterol increases, it may be that the significant decrease of the cholesterol ester fraction, induced by the slight galactosamine-liver injury, is not only effected by transacylation-inhibition in plasma.

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Unter experimenteller Mitarbeit von cand. med.B. Riese     

Zum Schlüpfprozess bei Fischen: I. Der Aufbau der Eihülle und ihre Veränderungen während der Keimesentwicklung bei der Forelle (Salmo trutta fario L.)

Summary The investigation of the egg shell ofSalmo trutta fario L. reveals several layers, which are chemically and physically different. During development of the egg, the chorion does not show notable changes in structure. Immediately at hatching the dissolution of the egg takes place as a result of the glands being on the head of the embryo.

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FräuleinBarbara Blum danken wir für ihre technische Hilfe.

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Der Deutschen Forschungsgemeinschaft sei für finanzielle Unterstützung gedankt.     

Artbastarde in der GattungTilapia (Cichlidae,Teleostei) und ihr Verhalten

Summary The young ofTilapia mossambica (mouth-brooder) show a characteristic contact-behaviour, which is related to the behaviour of the mother fish, who takes them back into the mouth cavity in cases of disturbance. This contacting is lacking in the young ofTilapia tholloni (substrate spawner). Contacting, as studied in our experiments with models, is genetically determined and is dominant over thetholloni pattern in the crossT. mossambica ×T. tholloni .     

Wirkungen von Gallensäure und Vitamin D auf die Kalziumresorption bei der Ratte

Summary Comparison of the effects of vitamin D and the bile salt Taurochenodeoxycholate on calcium absorption in young rats suggests that bile salt enhancement of calcium absorption occurs mainly in the ileum in normal animals but occurs in both duodenum and ileum in rachitic rats. Also suggested is that bile salts mainly assist the entry of calcium into mucosal cells from the gut lumen while vitamin D chiefly aids the egress of calcium from the cells into the extracellular fluid.