Postinflammatory changes of the diaphragmatic stomata

Authors
Citation
Kn. Michailova, Postinflammatory changes of the diaphragmatic stomata, ANN ANATOMY, 183(4), 2001, pp. 309-317
Citations number
54
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Experimental Biology
Journal title
ANNALS OF ANATOMY-ANATOMISCHER ANZEIGER
ISSN journal
0940-9602 → ACNP
Volume
183
Issue
4
Year of publication
2001
Pages
309 - 317
Database
ISI
SICI code
0940-9602(200107)183:4<309:PCOTDS>2.0.ZU;2-J
Abstract
Numerous investigations concerning the fine morphology of diaphragmatic sto mata have been performed, but its ultrastructural changes in experimental c onditions remain unclear. The present study demonstrates the peritoneal sid e of the diaphragm in adult Wistar rats by transmission electron microscopy . Ten experimental animals were observed 5 and 8 days after Pseudomonas aeu riginosa instillation (Pl) into the peritoneal cavity. A control group of 6 rats showed flat mesothelial covering on basal lamina (BL) and connective tissue layer, as well as cubic mesothelial cells, single stomata over under lying lymphatic lacunae (LL). Five days after PI the mesothelial cells had more numerous microvilli, microvesicles, vacuoles, lysosomes and a lesser n umber of specialized contacts. The multiplication of the extravasal cells a nd larger intercellular spaces lead to thickenings of the connective tissue around LL. LL were larger and located in close proximity of the mesotheliu m. Intercellular spaces in the mesothelial layer and different types of con tacts between mesothelial cells and endothelial protrusions of LL (with com mon BL or without BL) were encountered. Eight days after PI the mesothelium , endothelium of LL, their BL and surrounding connective tissue were interr upted and structurally modified to form typical new channels - stomata. The larger portion of the channels were formed of mesothelial cells, while the endothelial cells participated in the submesothelial part. LL were more nu merous than in the previous period, and were arranged in groups. LL increas ed their vertical (50.59 mum) and horizontal (155.57 mum) diameter, as comp ared with control animals (respectively 12.37 mum and 74.08 mum). Neighbour ing LL were separated by thin or thick septae. Peristomatal mesothelial cel ls or more rarely endothelium formed valve- or bridge-like structures. Valv es on the opposite side of LL were observed. Groups of electron-dense bodie s characterized some tall endothelial cells of LL. Cubic mesothelium, endot helium of the LL, both BL, the cell connections that formed new stomata, LL and surrounding connective tissue underwent rapid and parallel changes aft er PI. Among these elements of the lymphatic regions mentioned above, the m esothelium and endothelium of LL had a main role in experimental conditions .