ISSN:
1432-2307
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Light and electron microscope studies of lesions of the autonomic nervous system (ANS) in experimental Chagas' disease showed them to display irregular and unpredictable distribution, severely injured ganglia being found side by side slightly degenerated or even morphologically normal ones. The lesions were seen to present the following characteristics: 1. parasitism of the capsular fibroblasts and of the Schwann and satellite cells; 2. vacuole formation, in the host cells, induced by the presence of living parasite, no changes in the neighbouring tissue being observed; 3. acute focal inflammation (periganglionitis and ganglionitis) resulting from parasite of host cell degeneration and affecting the neighbouring structures (neurons and nerve fibers); 4. eventual organ denervation (already evidenced by optical microscopy) directly or indirectly triggered by multiple pathogenetic mechanism, no electivity of the Trypanosoma cruzi for the autonomic nervous system having been observed. In human trypanosomiasis cruzi, the ANS ultrastructural lesions (Auerbach plexus) in the megaesophagus, megacolon and jejunum showed to be essentially equal and similar to those observed in experimental infection, just differing in their intensity, being more discrete in the jejunum. All ganglia examined presented lesions in the neurons, in the Schwann cells and in the nerve fibers. In the same ganglion, degenerated neurons could be found side by side with normal healthy ones. The latter displayed some aspects that suggested the existence of a compensating mechanism. It was observed, for instance, that, in the megaesophagus, both granular and non-granular vesicles, seat of biogenous amines, were in large number than those present in the normal esophagus. This findings seems to indicate that peristaltic disturbances of the megaesophagus and megacolon are partially due to some change in the synthesis and in the liberation of biogenous amines from the nervous plexus of those organs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00548079
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