title: Caecal ligation and puncture induced sepsis in the rat results in increased brain water content and perimicrovessel oedema.
abstract: To investigate brain water content and ultrastructure in a rat caecal ligation and puncture (CLP) model of sepsis, adult male Wistar rats were assigned to one of the following experimental groups: CLP, Un-operated or Sham. CLP was performed under anaesthesia, Sham rats were exposed to anaesthesia, laparotomy and caecal mobilisation and Un-operated rats did not experience anaesthesia or surgery. CLP and Sham rats were sacrificed 18-20 h following recovery from surgery and Un-operated rats were sacrificed at the same time. Frontal cortex samples (CLP n = 9; Un-operated n = 10; Sham n = 8) were taken immediately post mortem and their water content determined using gravimetry. Similar samples were taken from other rats (CLP n = 8; Un-operated n = 8; Sham n = 8), processed for electron microscopy and subjected to morphometric analysis. There was significantly more brain water in CLP than Un-operated (P < 0.01) and Sham (P < 0.05) rats. Electron microscopy revealed significantly more peri-microvessel oedema in CLP than Un-operated (P < 0.001) and Sham rats (P < 0.05). Microvessel endothelial cell lumen cross-sectional area was significantly smaller in CLP than Un-operated (P < 0.001) and Sham (P < 0.05) rats and microvessel endothelial cell cross-sectional area was significantly smaller in CLP than Un-operated (P < 0.05) rats. Significantly more endothelial cell cytoplasmic area was occupied by mitochondria in CLP than Un-operated (P < 0.05) and Sham (P < 0.05) rats. However, experimental group did not affect the number of mitochondria present in endothelial cell profiles, or their cross-sectional area. Therefore, sepsis-induced cerebral oedema involves an increase in and a redistribution of brain water, together with ultrastructural changes to cerebral microvessels and adjacent tissue.
authors.affiliation: Division of Basic Medical Sciences, St George's University of London, London, UK.
authors.forename: Heather F
authors.initials: HF
authors.lastname: Brooks
authors.forename: Raymond F
authors.initials: RF
authors.lastname: Moss
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Davies
authors.forename: Rajiv
authors.initials: R
authors.lastname: Jalan
authors.forename: D Ceri
authors.initials: DC
authors.lastname: Davies
mesh_terms: D000818:Animals; D001834:Body Water; D001921:Brain / Q000378:metabolism* / Q000648:ultrastructure; D001929:Brain Edema / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000378:metabolism* / Q000648:ultrastructure; D008026:Ligation; D008297:Male; D046529:Microscopy, Electron, Transmission; D011677:Punctures; D051381:Rats; D017208:Rats, Wistar; D018805:Sepsis / Q000378:metabolism* / Q000473:pathology