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  • 1
    ISSN: 1432-0568
    Schlagwort(e): Autonomic nervous system ; Adrenergic nerves ; Chromaffin cells ; Pelvic viscera
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The organs of the lower abdominal and pelvic regions of the guinea-pig receive nerves from the inferior mesenteric ganglia and pelvic plexuses. The inferior mesenteric ganglia connect with the sympathetic chains, the superior mesenteric ganglia, the pelvic plexuses via the hypogastric nerves, and with the gut. Each pelvic plexus consists of anterior and posterior parts which send filaments to the internal generative organs and to the rectum, internal anal sphincter and other pelvic organs. The pelvic nerves enter the posterior plexuses, which also receive rami from the sacral sympathetic chains. The adrenergic neurons of the pelvic plexuses are monopolar, do not have dendrites and are supplied by few varicose adrenergic axons. Nearly all the nerves contain adrenergic fibres. After exposure to formaldehyde vapour the chromaffin cells appear brightly fluorescent with one or two long, often varicose, processes. Most of the chromaffin cells are in Zuckerkandl's organ or in chromaffin bodies associated with the inferior mesenteric ganglia. Groups of chromaffin cells are found along the hypogastric nerves and in the pelvic plexuses; they become smaller and fewer as regions more posterior to Zuckerkandl's organ are approached.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    ISSN: 1432-0568
    Schlagwort(e): Autonomic nervous system ; Adrenergic nerves ; Pelvic viscera ; Gastrointestinal tract
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The adrenergic innervation of the pelvic viscera was examined by the fluorescence histochemical technique, applied to tissue from untreated guinea-pigs and from guinea-pigs in which nerve pathways had been interrupted at operation. It was found that adrenergic neurons in the inferior mesenteric ganglia give rise to axons which run in the colonic nerves and end in the myenteric and submucous plexuses and around the arteries of the distal colon. In the rectum, part of the innervation of the myenteric plexus and all of the innervation of the submucous plexus comes from the inferior mesenteric ganglia. The rest of the adrenergic innervation of the myenteric plexus comes from the posterior pelvic ganglia or the sacral sympathetic chains. The innervation of the blood vessels of the rectum is from the posterior pelvic ganglia. Adrenergic nerves run from the sacral sympathetic chains and pass via nerves accompanying the rectal arteries to the internal anal sphincter. Other adrenergic fibres to the internal anal sphincter either arise in, or pass through, the posterior pelvic plexuses. The anal accessory muscle is innervated by adrenergic axons arising in the posterior pelvic plexuses. Adrenergic nerves which run in the pudendal nerves, probably from the sacral sympathetic chains, innervate the erectile tissue of the penis.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Pflügers Archiv 314 (1970), S. 1-13 
    ISSN: 1432-2013
    Schlagwort(e): Smooth Muscle ; Neuromuscular Transmission ; Electrophysiology ; Autonomic Nerves
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Intracellular microelectrodes were used to analyse the excitatory input to single cells of the mouse vas deferens. Excitatory junction potentials (EJP's) were evoked by both orthodromic and antidromic impulses in terminal axons lying within the musculature of the vas deferens, indicating that transmitter is released from the length of the terminal axon not just from the axon termination. The amplitude of the EJP was altered by altering the strength of stimulation. By using this variation, it was found that 15–22 nerve fibres gave a detectable contribution to the amplitude of the EJP in a single cell. The maximum amplitude of the EJP was 45 mV and the maximum depolarization caused by transmission from a single axon was 5 mV. By depolarizing the whole tissue with noradrenaline, the reversal potential for the EJP was found to be −20 to −15 mV. The EJP was not reversed when a single cell was depolarized with an intracellular current pulse. Extracellular electrodes failed to record any reversal of the EJP, corresponding to current sinks. It is concluded that the EJP in a single cell arises both from the action of transmitter, released from terminal varicosities, on its membrane and from potential changes electrically coupled from adjacent cells via low resistance connections between the smooth muscle cells.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Pflügers Archiv 317 (1970), S. 310-326 
    ISSN: 1432-2013
    Schlagwort(e): Potassium Ion ; Autonomic Nerves ; Neuro-Muscular Transmission ; Excitatory Junction Potentials ; Kaliumion ; Autonome Nerven ; Neuromusculäre Übertragung ; Erregungsübertragungspotentiale
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The effect of varying the potassium ion concentration on autonomic neuro-muscular transmission was studied in the vas deferens of the mouse. The smooth muscle cells had resting membrane potentials in normal solution of about 75 mV. The relationship between the membrane potential and the external potassium concentration was close to that predicted by the Nernst equation for external potassium concentrations above 20 mM. The relationship followed the trend predicted by the Goldman equation. The time of decay of the excitatory junction potential (EJP) in response to nervous stimulation decreased to one quarter when the potassium concentration was increased from 0 to 5 times that in normal solution. The transmission delay at the autonomic junction did not change, and the rise time of the EJP decreased only slightly, with increased external potassium concentration. The maximal amplitude of the EJP decreased with increased external potassium. Miniature EJPs (MEJPs) occurred spontaneously and had the same time course in each concentration of external potassium. In potassium-free solution spontaneous potentials, which were similar in time course to EJPs in the same solution, were also observed. It is concluded that the repolarizing phase of the EJP in normal solution is probably determined by the electrical properties of the smooth muscle.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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