Combined autoradiography and fluorescence microscopy. Localization of labelled 5-hydroxy-tryptophan in relation to endogenous 5-hydroxytryptamine in the gastrointestinal tract

Zusammenfassung Histologische Magen- und Duodenumschnitte der Maus wurden zur gleichzeitigen Lokalisierung biogener Amine und autoradiographischem Nachweis von injiziertem³H-5-HTP benutzt. Die Radioaktivität war in den enterochromaffinen Zellen lokalisiert und in den Zellen der Magenschleimhaut am höchsten. Fluoreszenz-Intensität und Silberkörnchen-Akkumulation zeigten ein entgegengesetztes Verhalten.     

Opposing temperature responses to intrahypothalamic injections of 5-hydroxytryptamine in the pigeon exposed to cold.

5-Hydroxytryptamine injected into posterior and anterior parts of the pigeon hypothalamus evoked a short lasting hyperthermia or hypothermia, respectively. Variable responses obtained within the same brain region suggest the existence of different 5-HT systems, even in rather limited hypothalamic areas.     

The role of sialic acid in 5-HT binding to synaptic membranes.

The high affinity binding of [14C]5-HT to nerve ending membranes isolated from rat brain is not affected by neuraminidase treatment. The specificity of ligand receptor interaction was demonstrated by displacement studies with tryptamine derivatives, noradrenaline, and acetylcholine.     

Cross-resistance of trichomonads to 5-nitroimidazole-derivatives

Summary The strainT. foetus KV 1/M 100, a sub-strain ofT. foetus Kv 1, was made highly resistant to metronidazole by several passages in mice under increasing drug pressure. This drug resistance was accompained by a remarkable cross-resistance to all 5-nitroimidazole-derivatives tested in vitro and in vivo.     

Neue Gesichtspunkte zum 5. Buch Euklids

Summary The author's purpose is to read the main work of Euclid with modern eyes and to find out what knowledge a mathematician of today, familiar with the works of V. D. Waerden and Bourbaki, can gain by studying Euclid's theory of magnitudes, and what new insight into Greek mathematics occupation with this subject can provide.The task is to analyse and to axiomatize by modern means (i) in a narrower sense Book V. of the Elements, i.e. the theory of proportion of Eudoxus, (ii) in a wider sense the whole sphere of magnitudes which Euclid applies in his Elements. This procedure furnishes a clear picture of the inherent structure of his work, thereby making visible specific characteristics of Greek mathematics.After a clarification of the preconditions and a short survey of the historical development of the theory of proportions (Part I of this work), an exact analysis of the definitions and propositions of Book V. of the Elements is carried out in Part II. This is done word by word. The author applies his own system of axioms, set up in close accordance with Euclid, which permits one to deduce all definitions and propositions of Euclid's theory of magnitudes (especially those of Books V. and VI.).In this way gaps and tacit assumptions in the work become clearly visible; above all, the logical structure of the system of magnitudes given by Euclid becomes evident: not ratio — like something sui generis — is the governing concept of Book V., but magnitudes and their relation of having a ratio form the base of the theory of proportions. These magnitudes represent a well defined structure, a so-called Eudoxic Semigroup with the numbers as operators; it can easily be imbedded in a general theory of magnitudes equally applicable to geometry and physics.The transition to ratios — a step not executed by Euclid — is examined in Part III; it turns out to be particularly unwieldy. An elegant way opens up by interpreting proportion as a mapping of totally ordered semigroups. When closely examined, this mapping proves to be an isomorphism, thus suggesting the application of the modern theory of homomorphism. This theory permits a treatment of the theory of proportions as developed by Eudoxus and Euclid which is hardly surpassable in brevity and elegance in spite of its close affinity to Euclid. The generalization to a classically founded theory of magnitudes is now self-evident.

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Vorgelegt von J. E. Hofmann     

Methiothepin and a 5-HT pathway to rat substantia nigra

Summary Methiothepin reduced both median-raphe evoked and exogenous 5-HT depression of single substantia nigra neurones. While this is compatible with a serotonin releasing pathway, additional interactions of methiothepin with exogenous dopamine suggest the need for further pharmacological confirmation.Acknowledgment. This work was supported by an MRC Programme Grant to Prof. D. W. Straughan     

High affinity binding of 5-hydroxytryptamine to some membrane preparations from cattle brain. Relationship to lysergic acid diethylamide (LSD)]

5 hydroxytryptamine binds to crude brain membrane preparations with two different affinities (KD = 1 to 2 X 10(-9) M for the highest, 1 to 2 X 10(-8) M for the lowest). LSD also binds with two affinities (KD = 3 to 4 X 10(-9) M and KD = 2 to 3 X 10(-8) M). Subcellular distribution of these sites shows that binding involves the two binding affinities in microsomal membranes but solely the high affinity binding sites are present in purified synaptosomal membranes. High affinity sites for 5 HT and for LSD are different as no direct competitive inhibition is observed in that case. On microsomal membranes, direct relationship occurs between low affinity binding for 5 HT and high affinity binding for LSD.     

Action of puromycin and 5-fluorouracil on the adrenal responsiveness to corticotrophin

Zusammenfassung Puromycin und 5-Fluorouracil beeinträchtigen in Nebennierenschnitten der Ratte die durch ACTH und cyclisches 3, 5-Adenosinphosphat stimulierte Corticosteronausscheidung. Die durch TPN plus Glukose-6-phosphat stimulierte Corticosteronausscheidung bleibt unbeeinflusst. Dagegen bewirkt Puromycin bei Zusatz von TPN allein eine Hemmung. Die Wirkung von Puromycin und 5-Fluorouracil dürfte daher eher auf die Beeinflussung des Energiestoffwechsels als auf eine Hemmung der Neubildung induzierter Enzyme zurückzuführen sein.     

Phytochemical studies. Isolation of 5-ethyltropolone fromLibocedrus formosana

Zusammenfassung Es wird die Isolierung eines neuen Nortropolon-Derivates beschrieben.

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For the previous paper in this series see: Y.-T.Lin, K.-T.Wang, and B.Weinstein, Chem. Commun., 592 (1965).     

Response of adrenal and preputial glands of rats to administration of 5-hydroxytryptamine

Zusammenfassung An weiblichen intakten, adrenal- oder ovariektomierten und sowohl adrenal-, als auch ovariektomierten Ratten wurden 2 h nach Injektion von 5-Hydroxytryptamin die Gewichtsveränderungen und der Ascorbinsäuregehalt der Nebennieren und der Präputialdrüsen untersucht. Eine Abnahme des Ascorbinsäuregehaltes der Nebennieren und der Präputialdrüsen wurde festgestellt und eine Gewichtszunahme der Präputialdrüsen selber beobachtet. Die Ergebnisse stimmen mit den bekannten Befunden über eine ACTH-freisetzende Tätigkeit des 5-Hydroxytryptamins überein.     

The response of cyclic 3',5'-AMP and cyclic 3',5'-GMP phosphodiesterases to experimental diabetes

Alloxan diabetes caused a decrease in cyclic AMP phosphodiesterase in all affected rat tissues. Cyclic GMP phosphodiesterase activity was, however, decreased in adipose and liver, but increased increased in heart and uterus.     

The response of cyclic 3′,5′-AMP and cyclic 3′,5′-GMP phosphodiesterases to experimental diabetes

Summary Alloxan diabetes caused a decrease in cyclic AMP phosphodiesterase in all affected rat tissues. Cyclic GMP phosphodiesterase activity was, however, decreased in adipose and liver, but increased in heart and uterus.This research was supported by U.S. Public Health Service grant RO1-AM19364-O1 and MARC training grant No. 1-TO2-GMO50000.     

Adenosine 5'-triphosphate sulphurylase from Spirulina platensis.

ATP-sulphurylase from an unicellular blue-green alga, Spirulina platensis was localized in the soluble fractions of cell-free homogenate, and it was stable for over 3 weeks at -6 degrees C.