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Summary The distribution of monoamines in the pharynx and oesophagus of the rhesus monkey (Macacus rhesus) and the cat (Felis domestica) was investigated by means of fluorescence microscopical and chemical methods. Fluorimetric determinations reveal the presence of varying amounts of noradrenaline in the pharynx and oesophagus of the rhesus monkey. The lowest amount (0.05 (g/g) was found in the lower part of the oesophagus, the so-called sphincter-segment. The middle and upper part of the oesophagus contain medium amounts of noradrenaline (0.06–0.09 g) whereas the highest concentration was detected in the pharynx (0.14 (g/g). Neither dopamine nor adrenaline occurred in the tissue pieces analyzed. Fluorescence microscopically noradrenaline was found to be located in varicose intramural nerve fibre plexus which innervate mucous glands and blood vessels in the pharynx of both species. In the rhesus monkey, the lamina muscularis mucosae of all parts of the oesophagus is supplied by a well developed noradrenergic ground-plexus. Preterminal and terminal varicose nerve fibres are distributed in myenteric and submucous ganglia of the oesophagus; the number of such ganglia decreases towards the lower segment. The density of the adrenergic innervation is higher in myenteric when compared to submucous ganglia. The arrangement of the intraganglionic terminals suggests that both axosomatic and axodendritic contacts occur in Auerbach's ganglia whereas axodendritic contacts seem to predominate in Meissner's ganglia. Myenteric ganglia situated close to the submucosa as well as true submucous ganglia may be occasionally seen to be traversed by faintly fluorescent non-varicosed fibres which do not establish any synaptic contacts. The fluorescence intensity of intraganglionic varicosities varies considerably; accordingly the transmitter content of individual varicosities seems to be very variable. The adrenergic innervation of the lamina muscularis is restricted to single contorted fibres being sparsely distributed throughout the longitudinal smooth muscle layer. The circularly arranged smooth musculature of the sphincter-segment lacks an adrenergic nerve supply. The vagus nerve carries sympathetic adrenergic fibres to the lower oesophagus and the cardia. Species differences between the innervation pattern in rhesus monkeys and cats are outlined: No adrenergically innervated ganglia occur in the submucosa of the cat. However, part of the myenteric ganglia in cats exhibit an adrenergic innervation pattern similar to that seen in submucous ganglia of the rhesus monkey. They might therefore be regarded as morphologically equivalent to the plexus submucosus which is, however, present in the whole gut. The density of the noradrenergic ground-plexus in the muscularis mucosae of the cat's oesophagus is less than that of the corresponding plexus in rhesus monkeys.The influence of noradrenaline upon the smooth musculature and the neurons from myenteric as well as submucous ganglia is discussed. From the point of view of the adrenergic innervation there is no structure corresponding to the sphincterlike lower oesophageal segment.Supported by the Deutsche Forschungsgemeinschaft and the Joachim-Jungius-Gesellschaft zur Förderung der Wissenschaften, Hamburg. 相似文献
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Summary Clinical observations and the light and electron microscopic appearance of the adrenal cortex are described in a case of Cushing's disease associated with adrenocortical hyperplasia and a basophilic adenoma of the pituitary gland. The electron microscopic investigation concentrates upon the occurrence of osmiophil material in the different cytoplasmic compartments of the cell type rich in organelles and relatively poor in paraplasmic inclusions. It seems that the observation of osmiophil material in the perinuclear space, the mitochondrial matrix, Golgi vacuoles, and cytoplasmic vesicles has been made possible by a rather long fixation in Wohlfarth-Bottermann's chromium-osmium fixative. Mitochondria and related particles (named X-Einschlüsse) may contain a light center with a few dense filaments and masses resembling those described by other authors as being of deoxyribonucleic acid nature. Relatively large Golgi complexes are found, sometimes in close topographic relation with a centriole. A large population of osmiophil bodies (lipid droplets, pigment granules, microbodies) is described. Apart from these findings the cytoplasmic organization in the tissue studied is similar to that of the adrenal cortex as described in other mammals. The observations are discussed with respect to hypotheses about lipid droplet formation and to the possibility of artifacts due to preparation procedures.
Herrn Prof. Dr. med. W. Bargmann zum 60. Geburtstag gewidmet. — Herrn Prof. Dr. E. Uehlinger, Direktor des Pathologischen Instituts der Universität Zürich, danken wir für die Überlassung des Materials und für die freundlicherweise zur Verfügung gestellte pathologisch-anatomische Diagnose, dem Schweizerischen Nationalfonds für die Unterstützung und Frau Jäger, Mlle. Challamel und Herrn Krieger für die Ausführung der histologischen und photographischen Arbeiten. 相似文献
Herrn Prof. Dr. med. W. Bargmann zum 60. Geburtstag gewidmet. — Herrn Prof. Dr. E. Uehlinger, Direktor des Pathologischen Instituts der Universität Zürich, danken wir für die Überlassung des Materials und für die freundlicherweise zur Verfügung gestellte pathologisch-anatomische Diagnose, dem Schweizerischen Nationalfonds für die Unterstützung und Frau Jäger, Mlle. Challamel und Herrn Krieger für die Ausführung der histologischen und photographischen Arbeiten. 相似文献
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M. Klinkowski H. Lange Fabig M. Schmidt K. Wuttky J. Helm Hagemann F. Mechelke Buder Reinmuth Alfred Lein W. Laube A. Wetzel 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1960,30(6):258-264
Ohne Zusammenfassung 相似文献
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