Pathways for excitatory and inhibitory innervation to the guinea-pig tracheal smooth muscle.

The trachea receives excitatory cholinergic innervation from the vagus nerve and the stellate ganglion. Inhibitory adrenergic fibres have the same sources. Those in the vagus nerve probably derive from high vagosympathetic anastomoses. Nonadrenergic inhibitory fibres have a preganglionic vagal supply.     

The effect of urethane on histamine-induced contraction of guinea-pig tracheal smooth muscle

Summary Urethane possesses a direct depressant action on histamine-induced contractions of guinea-pig tracheal smooth muscle both in vivo and in vitro.     

Calcium and the contractile response to prostaglandin in the smooth muscle of guinea-pig stomach

Summary In the longitudinal smooth muscle of guinea-pig stomach, verapamil (10^–5 M) which showed marked suppression of high K-induced contractures, did not suppress the contractile response to PGE₁ (1.5×10^–9 to 10^–6 M) markedly. These results suggest that the contractile mechanism of PGE₁ in guinea-pig stomach may mainly depend on a release of bound Ca in the cell and partly depend on a Ca influx from the extracellular origin.     

Electrical slow waves in oviductal smooth muscle of the guinea-pig,mouse and the immature baboon

Summary Oviducts of the guinea-pig, mouse and immature baboon show prominent electrical slow waves. In the guinea-pig oviduct they are 40–50 mV in amplitude and have a duration of 1.5 sec in the isthmus. Slow waves in these tissues propagate at a speed of 1–13 mm/sec.Decreased 6th December 1977.Supported by NIH-09339-02 and Rockefeller Foundation. A. T. was a Rockefeller Foundation Fellow. Correspondence to B. J. Hodgson, Dept. Obstetrics and Gynecology, UTHSCSA, San Antonio, Texas 78284.     

The inhibitory action of caffeine on the smooth muscle of the guinea-pigTaenia coli

Zusammenfassung Nachweis des muskelrelaxierenden (elektolischen und mechanischen) Effektes von Koffein auf den Meerschweinchendarm erst reizend und sekundär hemmend. Am K-kontrahierten Präparat führte Koffein zur Erschlaffung, die bei Erhöhung des extrazellulären Ca verändert wurde.     

Adrenergic innervation of the intestinal smooth musculature

Riassunto Le ricerche istochimiche effettuate sull'innervazione adrenergica dell'intestino hanno dimostrato che fibre adrenergiche sono presenti non solo attorno ai neuroni e nelle maglie dei plessi mienterico e sottomucoso, ma anche nello spessore stesso dello strato muscolare interno e in intimo rapporto con elementi ghiandolari della tonaca mucosa. Vi è quindi la possibilità che sugli effettori ghiandolari e muscolari le fibre adrenergiche esercitino sia un'azione diretta sia un'azione indiretta attraverso i neuroni intramurali.

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This work was supported by a grant from the Consiglio Nazionle delle Ricerche (Rome).     

Spikes of smooth muscle in calcium-free solution (isolated taenia coli of the guinea-pig)

Zusammenfassung An der glatten Darmmuskulatur (Taenia coli) des Meerschweinchens konnten nach völligem Entzug von Kalzium (und Magnesium) aus der Nährlösung über lange Zeit Spikes gemessen werden. Diese kalziumfreien Spikes werden, im Gegensatz zu den Spikes unter normalen Bedingungen, durch Tetrodotoxin 10^–5 blockiert, und sie werden wie die normalen Spikes mit 100fach niedrigerer Schwelle durch Manganionen blockiert. Es wird angenommen, daß Na-Ionen die für diese Spikes verantwortlichen Ladungsträger sind.

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This work was supported by a grant from the Deutsche Forschungsgemeinschaft (No. Go 130/7).     

The effect of the venom of the digger wasp Philanthus on the fast and slow excitatory and the inhibitory system in the locust muscle

Zusammenfassung Es wird gezeigt, dass das Gift der Wespe Philanthus triangulum F. bei der Heuschrecke eine reversible Muskellähmung bewirkt, die auf einer Blockierung der Axon-Muskel-Synapse der «schnellen» Faser beruht. Die Synapse der langsamen und hemmenden Faser wird offenbar nicht beeinflusst.

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This work has been supported in part by the European Research Office, United States Army, Frankfurt am Main, Germany.

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Acknowledgments: I am indebted to Prof. Dr. C.van der Meer for his constant help and criticism and to Dr. R. T.Simon Thomas for providing the wasps. I wish to thank Mr. E.Engels for all the technical work.     

Effect of drugs on excitatory and inhibitory potentials inHelix aspersa

Résumé Des produits chimiques furent injectés à l'escargotHelix aspersa. Leur effet fut enregistré en potentiels postsynaptiques. L'hemicholinium réduit l'amplitude d'un potentiel postsynaptique d'excitation cholinergique. L'-Methyl-5-HTP et lep-chlorophenylalanine ou résperpine font décroître l'amplitude d'un potentiel postsynaptique d'exication 5-HT, le 6-Hydroxydopamine diminue celle d'un potentiel postsynaptique d'inhibition dopamine tandis que le DOPA l'augmente.     

An inhibitory action of caerulein on the isolated guinea-pig ileum

Riassunto La caeruleina provoca sull'ileo di cavia isolato una inibizione dello spasmo sostenuto da dosi massimali di istamina. Questo effetto inibitorio sembra connesso con le proprietà colecisto-chinino simili del peptide più che con quelle gastrino simili.     

Sherrington was right about the Trapezius muscle innervation

Zusammenfassung Beim Eichhörnchen,Saimiri sciureus wurde elektromyographisch gezeigt, dass die Nerven in der Region der Nackenwirbelsäule den Trapeziusmuskel mit innervieren. Der obere Anteil dieser über den Trapezius verteilten Bewegungsinnervationen enthält stärkere Beteiligung durch die Nackenbewegungsinnervation.     

Time course of excitatory and inhibitory states of bulbar respiratory modulated neurons

Summary In respiratory modulated neurons of rabbits, vagally mediated inhibition is not bound to resting membrane potential oscillations. Latency of spinally evoked antidromical spike invasion, however, is shorter and threshold voltage is lower during the shift of membrane potential towards depolarization accompanying burst discharge.     

Smooth muscle of the pancreatic duct of the cat and its innervation

Zusammenfassung In der Wandung desDuctus pancreaticus major der Katze wird eine dünne Schicht von Muskelfaserzügen beschrieben. Histochemisch wird festgestellt, dass es sich bei fehlender adrenergischer um cholinerge Innervation dieser Muskelzellen handelt.

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J. R. Garrett, wishes to express his gratitude to the Royal Society for travel grants that made this work possible.