Cholecystokinin-like peptides in avian brain and gut.

Extracts of turkey brain and jejunum contain a factor closely resembling the COOH-terminal octapeptide of porcine cholecystokinin (CCK). Turkey antral extracts contain factors distinguishable in immunochemical and gel filtration properties from the mammalian forms of gastrin and CCK.     

Role of neurotransmitter release and cyclic AMP-dependent membrane phosphorylation in low voltage myocardial automaticity

Summary Low voltage myocardial automaticity (LVA) was investigated by pharmacological modulations of the presynaptic and postsynaptic processes. The sensitivity of LVA both to inhibitor and stimulator of neutrotransmitter release suggests its involvement in LVA genesis. Moreover, LVA is blocked by the inhibition of the cyclic AMP system, supporting the participation of the c-AMP-dependent membrane phosphorylation in calcium-mediated cardiac electrogenesis.Acknowledgment. The generous gift of RM1 12330A from Prof. G. Guellen, Paris, and of tolbutamide from Prof. T. Hayakawa, Tokyo, are gratefully acknowledged.     

AnAnolis skin melanophore assay suitable for photoaffinity labeling studies with α-MSH

Summary Visual determination of MSH-induced pigment migration in melanophores of small pieces ofAnolis carolinensis skin is standardized by first measuring photoelectrometrically the change in reflection/transmission of the whole dorsal skin in response to different hormone concentrations. This method allows the rapid and precise recording of time-response curves after photoaffinity labeling of MSH receptors or of dose-response curves of large series of synthetic compounds.Acknowledgments. We wish to thank Ms V. Jäggin, Ms C. Schulthess and Ms G. van Hees for excellent technical assistance, Dr. R. Andreatta, Ciba-Geigy AG, Basel, for his generous gift of -MSH and Prof. A Pletscher for his continuous interest. This work was supported by the Swiss National Science Foundation.     

Cytopathological effects of aristolochic acid on male houseflies causing sterility

Summary Feeding male houseflies with 0.075% aristolochic acid obtained from the plants of the genusAristolochia induced sterility. High condensation of chromosomes, and breakages, have been shown to be responsible for sterility. When onion roots were exposed to aristolochic acid similar chromosomal aberrations were noticed in cells at the tip.Authors are thankful to Prof. Dr G. Rücker (Universität Bonn) for a generous gift of aristolochic acid.     

Zur Struktur von Scotophobin

Summary The biological and chemical properties of one of the synthetic peptides Seryl-asparagil-asparaginylasparaginyl-glutaminyl-glycyl-glycy-lysyl-seryl-alanyl-glutaminyl-glutaminyl-glycyl-glycyl-tyrosylamid are identical with those of the natural scotophobin.

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Wir danken der Robert A. Welch Foundation, Houston, Texas, für die finanzielle Unterstützung dieser Arbeit. Herrn Prof. Dr.G. Ungar, Baylor College of Medicine, Houston, Texas danken wir für die Ausführung der biologischen Tests.     

Bovine TSH-stimulation of fish thyroid peroxidase activity and role of thyroxine thereon

Summary bTSH augmented the fish thyroid peroxidase activity in a dose-response manner. Thyroxine could not modulate the effect of exogenous bTSH, but it decreased the peroxidase activity in a control system when administered alone. The data therefore suggest similar negative feedback control system for TSH-regulation as operative in the case of mammals.Acknowledgment. We are thankful to Prof. A. B. Das, Head of the Department of Zoology, Visva-Bharati University, Santiniketan, for providing laboratory facility. We are greatly indebted to Dr A. G. Dutta for his kind gift of bovine TSH (NIH-B5).     

Effects of precocene II and juvenile hormone III on the activity of neurosecretory A-cells inOncopeltus fasciatus

Summary Application of precocene II, topically or by contact method, appears to inhibit the synthetic activity of neurosecretory A-cells of the pars intercerebralis ofOncopeltus fasciatus. Treatment of precocene-treated insects with JH III apparently stimulates the secretory activity of these cells.Supported by National Research Council of Canada grant No. A4669.We thank Dr G. B. Staal, Zoecon Corporation, Palo Alto, California, for the gift of precocene II.     

Effect of cadmium on polyribosome structure and function in mouse liver

Summary Cadmium chloride injected to mice (20 moles/kg) provokes in the livers a degradation of polyribosomes and diminishes their protein synthetic ability measured in vitro. CdCl₂ added in a final concentrations between 30 and 100 M to the protein synthetic cell-free system derived from livers of control mice inhibits its activity.Acknowledgments. We are grateful to Prof. P. Sokoli for helpful discussion. The work was supported by Wellcome Trust grant and by a gift of chemicals from Kemika, Zagreb. We are grateful to both these organizations.     

Giffordene, 2Z, 4Z, 6E, 8Z-undecatetraene,is the odoriferous principle of the marine brown algaGiffordia mitchellae

Summary Giffordene, 2Z, 4Z, 6E, 8Z-undecatetraene, and five stereoisomers are new odoriferous C₁₁H₁₆-hydrocarbons from the marine brown algaGiffordia mitchellae. Their isolation and identification is described.Acknowledgments. We thank Prof. G. Ohloff for kindly providing us with synthetic 1,3,5,7-undecatetraenes and Prof. P. Schreier for GC/FTIR-analyses.     

Two new kaempferol 3,7-diglycosides and kaempferitrin in the fernAsplenium trichomanes

Summary The fronds of the fernAsplenium trichomanes contain kaempferol 3,7-dirhamnoside (1) and the new compounds kaempferol 3-O-a-rhamnoside-7-O-a-arabinoside (2) and kaempferol 3-O-a-arabinoside-7-O-a-rhamnoside (3). The presence of the above flavonoids has been shown by spectroscopic methods and chemical degradations.Acknowledgments. The author thanks Prof. H. Wagner (Institut für pharmazeutische Arzneimittellehre der Universität München, München) for a sample of kaempferol 3,7-dirhamnoside, Dr K. R. Markham (Chemistry Division, D.S.I.R., Petone, New Zealand) for a gift of pectinase and Mr A. D'Urso (Botanic Institute, University of Catania) for help in acquiring the plant material.     

Radioimmunoassay of an invertebrate peptide hormone — the crustacean neurosecretory hyperglycemic hormone

Summary Antibodies against hyperglycemic hormone (CHH) ofCarcinus were raised in rabbits by injection of extract from sinus glands which contain high concentrations of CHH. The antiserum neutralizes the biological activity of CHH and binds¹²⁵J-CHH. A RIA for CHH was established and was used to measure the hormone content of sinus glands.Dedicated to Prof. M. Gersch, Jena, on the occasion of his 70th birthday.This study was supported by the Deutsche Forschungsgemeinschaft (Ke 206/2).We thank S. Grabig. E. schmid and B. Reichwein for expert technical assistance, and Dr D. Breitig and G. Kegel for critical discussions.     

Bromocriptine-induced removal of endoplasmic membranes from prolactinoma cells

Summary Adenomatous prolactin cells lose 39% of their cytoplasm volume within 7 days after the beginning of bromocriptine treatment. A simultaneous reduction of the rough-surfaced endoplasmic reticulum and the Golgi apparatus occurs. Their membranes are removed by rapid transport along the secretory pathway to the cell surface and to lysosomal destruction.We thank Prof. E. del Pozo, Sandoz Ltd, Basle, for the generous gift of injectable bromocriptine, Prof. E.R. Weibel, Dept. of Anatomy, University of Bern, for his technical advice, Dr U. Helfenstein, Institute of Biostatistics, University of Zürich, for his help in the statistical evaluation of the results and the EMDO-Foundation, Zürich, for financial support.     

Tetraploidy inProtopterus (Dipnoi)

Summary Comparative DNA values obtained by Feulgen cytophotometry for 3 species ofProtopterus, as well as karyotype analysis, show the existence of a diploid-tetraploid relationship within the genusProtopterus.Research supported by the Division of Human Genetics, K. U. Leuven, Belgium, and by the Université Nationale du Zaire, campus Kinshasa, Zaire. The Department of Human Genetics, University of Amsterdam. The Netherlands, provided laboratory facilities for cytophotometric analysis. I thank J. Bylsma, A. Debont, F. Koperdraad and H. Van den Berghe for advice, R. Ruysschaert and G. Warmoes for hospitality and technical assistance and T. Mohsen for the generous gift ofP. annectens from Senegal.     

Peroxidase uptake by the fat body of a millipedeSpirostreptus asthenes (diplopoda,myriapoda)

Résumé On a observé chez un mille-pattes (Spirostreptus asthenes) que la péroxidase injectée dans le sang a été trouvée plus tard dans le corps gras, ce qui suggère que celui ci est capable d'isoler la protéine du sang.

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I am thankful to Prof. Dr.G. Krishnan for guidance and helpful criticism. I am greatly indebted to Dr.Locke, Case Western Reserve University, USA, for the gift of horse radish peroxidase and for independent verification of the results.     

Effect of prolactin on human red cell sodium transport

Summary Incubation of red cells with higher concentrations of prolactin in vitro enhanced the cellular sodium level and produced a significant reduction in erythrocyte membrane adenosine triphosphatase activity. This effect was dose and time-dependent. It is the result of an inhibition of the active sodium pump similar to that produced by ouabain, suggesting altered red cell function and electrolyte balance in hyperprolactinemic states.Acknowledgments. Ovine prolactin was generously supplied by Ferring (Malmö, Sweden) and NPA, NIH (Maryland, USA). Thanks are also due to Prof. S. Dutta, Wayne State University, Detroit, for the gift, of ouabain octahydrate and Dr M. Ramachandran and Prof. S. Ramakrishnan, Department of Biochemistry, JIPMER, Pondicherry, for their encouragement and keen interest in this study.     

Participation of microtubules and microfilaments in the transcellular biliary secretion of immunoglobulin A in primary cultures of rat hepatocytes

Summary The biliary secretion of immunoglobulin A (IgA) in primary hepatocyte cultures was investigated by means of immunofluorescence. The characteristic accumulation of IgA in visible bile canaliculi was found to be strongly inhibited by vinblastine and colchicine or by cytochalasin B, but its surface binding was not.The author thanks Prof. Dr D. Mecke for his support and encouragement. The excellent technical assistance of Mrs M. Behringer and Mrs A. Schneck is gratefully acknowledged. The author is grateful to the BIOTEST Serum Institut (Frankfurt) for the kind gift of human IgA. This work was supported by the Deutsche Forschungsgemeinschaft.     

Phalloidin poisoning of isolated hepatocytes: Inhibition of protein synthesis

Summary Phalloidin added to isolated hepatocytes inhibits amino acid incorporation into protein. Inhibition is very strong with 20 g/ml phalloidin and occurs after a lag period of about 30 min. After this period, poisoned hepatocytes also show morphological changes in their plasma membrane.This work was aided by a grant from the Consiglio Nazionale delle Ricerche, Roma.We thank Prof. Th. Wieland, Max-Planck-Institut, Heidelberg (Federal Republic of Germany), for the gift of phalloidin.     

The effects of diltiazem onPeriplaneta americana

Summary The effects of the calcium antagonist diltiazem on nerve and muscle in the cockroachPeriplaneta americana were examined. Diltiazem was observed to inhibit myogenic and glutamate-induced contractions of the visceral muscle while having either a potentiating, an inhibiting or a biphasic effect against proctolin-induced contractions. Against the isolated nervous system, diltiazem induced an increase in spontaneous discharge activity, followed by nerve block. Injection of diltiazem into cockroaches produced behavioral and toxic effects.Acknowledgments. The expert technical assistance of Miss Susan Auffarth is gratefully acknowledged. Bioresmethrin was provided by Dr. G.J.P. Singh. We would like to thank Nordic Laboratories for the gift of diltiazem.     

Effect of phosphonic analogues of glutamic acid on glutamate decarboxylase

Summary Among the phosphonic analogues of glutamic acid, only 4-amino-4-phosphono butyric acid, the compound which shows the highest affinity for pyridoxal phosphate, inhibits competitively bothEscherichia coli and rat brain glutamate decarboxylases. Phosphinothricin, 2-amino-4-(methylphosphino)butyric acid, is a strong inhibitor of the mammalian enzyme.We acknowledge the gift of a sample of phosphinothricin by Prof. Przemyslaw Mastalerz as well as the technical assistance of Denois.     

Presence of ecdysone and ecdysterone in the tickAmblyomma hebraeum Koch

Summary Ecdysone and ecdysterone, the moulting hormones of insects and crustaceans, are also present in nymphs of the tickAmblyomma hebraeum. They were demonstrated by means of radioimmunoassay and of gas-liquid chromatography combined with mass fragmentography or mass spectrometry of their trimethylsilyl-drivatives.Acknowledgments. We thank Proff. A. Aeschlimann and C. Noirot and Dr J. Delachambre for their help and encouragement. We are grateful to Proff. Maume and Padieu (Département de Biochimie, Université de Dijon) for the use of the LKB 9000 GLC-MS, and to Drs M. L. De Reggi, M. H. Hirn and Prof. M. A. Delaage for the gift of some RIA-antigens and antibodies. We thank Ciba-Geigy Ltd for the supply with ticks. The work was in part supported by grant Nr. 3. 734. 76 of the Swiss National Science Foundation and by a grant of the Emil Barrel Stiftung.