Ultrastructural changes of the intracellular surfactant pool in a rat model of lung transplantation-related events


Ischemia/ reperfusion (I/R) injury, involved in primary graft dysfunction following lung transplantation, leads to inactivation of intra-alveolar surfactant which facilitates injury of the blood-air barrier. The alveolar epithelial type II cells (AE2 cells) synthesize, store and secrete surfactant; thus, an intracellular surfactant pool stored in lamellar bodies (Lb) can be distinguished from the intra-alveolar surfactant pool.

The aim of this study was to investigate ultrastructural alterations of the intracellular surfactant pool in a model, mimicking transplantation-related procedures including flush perfusion, cold ischemia and reperfusion combined with mechanical ventilation.

Methods: Using design-based stereology at the light and electron microscopic level, number, surface area and mean volume of AE2 cells as well as number, size and total volume of Lb were determined in a group subjected to transplantation-related procedures including both I/R injury and mechanical ventilation (I/R group) and a control group.

Results: After I/R injury, the mean number of Lb per AE2 cell was significantly reduced compared to the control group, accompanied by a significant increase in the luminal surface area per AE2 cell in the I/R group. This increase in the luminal surface area correlated with the decrease in surface area of Lb per AE2.

The number-weighted mean volume of Lb in the I/R group showed a tendency to increase..

Conclusion: We suggest that in this animal model the reduction of the number of Lb per AE2 cell is most likely due to stimulated exocytosis of Lb into the alveolar space. The loss of Lb is partly compensated by an increased size of Lb thus maintaining total volume of Lb per AE2 cell and lung.

This mechanism counteracts at least in part the inactivation of the intra-alveolar surfactant.

Author: Lars KnudsenHazibullah WaizyHeinz FehrenbachJoachim RichterThorsten WahlersThorsten WittwerMatthias Ochs
Credits/Source: Respiratory Research 2011, 12:79



Published on: 2011-06-14



News Provider: 7thSpace Interactive

Copyright by the authors listed above - made available via BioMedCentral (Open Access). Please make sure to read our disclaimer prior to contacting 7thSpace Interactive. To contact our editors, visit our online helpdesk. If you wish submit your own press release, click here.

Social Bookmarking
RETWEET This! | Digg this! | Post to del.icio.us | Post to Furl | Add to Netscape | Add to Yahoo! | Rojo



Comments

There are no comments available. Be the first to write a comment.


You need to enable Javascript to post a comment.


Custom Search

Username
Password










© 2014 7thSpace Interactive
All Rights Reserved - About | Disclaimer | Helpdesk
There are currently 23423 people browsing 7thSpace (S2)