Activity increases quantal size at the frog neuromuscular junction

Summary Two h of nerve stimulation at 10 Hz or of elevated spontaneous release in hypertonic solution increased the size of miniature end-plate potentials (m.e.p.p.'s) and currents at the frog neuromuscular junction, probably by increasing the amount of acetylcholine in a quantum. Increases in quantal size may modulate synaptic transmission.Acknowledgments. Supported by grant 10320 from the NINCDS and by a grant from the MDA. We are grateful to Dr I.S. Cohen for participating in some of the experiments and for helpful criticism, and to Drs C. Clausen and G. Baldo for help with the computer. Some of the results were presented at a meeting of the Physiological Society.     

Decidua and the control of corpus luteum function, follicular development and pituitary LHRH-responsiveness in pseudopregnant and pregnant rats

The mid-pregnancy rescue of corpora lutea can be mimicked in the pseudopregnant rat by induction of decidual tissue in the uterus: in such rats, around day 10, there is neither luteolysis, nor resumption of follicle-development or increase of the pituitary responsiveness to LHRH. The results suggest that the mid-pregnancy rescue of corpora lutea is caused by a maternal factor.     

Studies on the modulation of the desensitization of the pituitary gland by luteinizing hormone-releasing hormone in the ovariectomized rat

Summary In ovariectomized rats the desensitization of the LH cells in vivo, which develops during constant rate infusion of LHRH, 1) does not depend on a concomitant depletion of the pituitary LH stores, 2) proceeds normally when the hypothalamo-pituitary connection has been severed and 3) is a process in which LH itself is not involved.     

The effect of weak electrical potential gradients on the transport of water in broad bean plants under stress

Summary Adequate moisture was transported by an electrical potential gradient of 1 V/cm of the correct polarity to maintain the turgid state of broad-bean plants subjected to severe stress conditions.Acknowledgments. A.P. is grateful to the University of stellenbosch for the financial aid and the privilege of conducting research on their premises.     

Effect of bromelain (ananase?) on human platelet aggregation

Zusammenfassung Die orale Verabreichung von Bromelain in Form von 2 Ananase^®-100-Tabletten an freiwillige Versuchspersonen verminderte bei diesen die Empfänglichkeit für die durch ADP induzierte Aggregation der Blutplättchen.

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This work was supported by the Honolulu Chamber of Commerce research grants.     

Interferenzmikroskopische Untersuchungen an Medulloblastom- und Glioblastomzellen

Summary The dry mass per unit area (g/µ²) for nucleus and cytoplasma was determinated by interference microscope from 1043 glioblastoma cells of 5 various glioblastomas and from 439 medulloblastoma cells of 4 various medulloblastomas. The values obtained from the glioblastoma cells are significantly higher than the values of medulloblastoma cells.

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Mit dankenswerter Unterstützung der Deutschen Forschungs gemeinschaft.     

d-Aminosäurehaltige Analoga des Eledoisins

Summary The synthesis of several C-terminal eledoisin heptapeptide analogues, containing 1–5d-amino acids, is described and the biological activities are discussed.

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Über Peptidsynthesen XXXI. 4. Mitt. über Eledoisin und Eledoisin-Analoga. 3. Mitt. über Eledoisin und Eledoisin-Analoga:K. Lübke undE. Schröder, Liebigs Ann., im Druck.

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Auszugsweise vorgetragen auf dem VII. Europäischen Peptidsymposium, September 1964 in Budapest.