[Study on changes in circulatory renin-angiotensin system in rats with endotoxemia].
OBJECTIVE
To investigate the changes in circulatory renin-angiotensin system (RAS) in rats with endotoxemia and explore its mechanism.


METHODS
Ninety Wistar rats were randomly divided into normal control group (n=10) and endotoxemia groups (n=80). The endotoxemia group was further divided into subgroups of 2, 4, 8, 12, 24, 48, 72 hours and 7 days after injection of lipopolysaccharide (LPS) into the abdominal cavity (each n=10). The rats were sacrificed at different time points after LPS (10 mg/kg) challenge. Contents of plasma LPS, plasma renin activity (PRA), plasma angiotensin II (A II), angiotensin-converting enzyme (ACE), tumor necrosis factor-alpha (TNF-alpha), and interleukin-10 (IL-10) were determined.


RESULTS
(1) Plasma LPS, TNF-alpha and IL-10 reached highest levels 2 hours after LPS injection, and they returned to normal levels 7 days, 8 hours and 8 hours after LPS challenge respectively. (2) The levels of plasma PRA, A II and ACE reached highest levels 2, 8 and 8 hours after LPS challenge respectively, and they returned to normal levels 12, 24 and 72 hours after LPS injection, respectively.


CONCLUSIONS
During endotoxemia, there is a series of inflammatory reactions and anti-inflammatory reactions, and a large number of cytokines and inflammatory mediators are released. At the same time, the circulating RAS is activated, which causes constriction of blood vessel and dysfunction of the microcirculation aggravating hypoxia of cells. The study of the changes in RAS is significant to interpreting the pathogenetic mechanism of endotoxemia in rats.
Li
Jing-ling
JL
Capital University of Medical Science, Beijing Friendship Hospital, Beijing 100050, China.
Yin
Cheng-hong
CH
Wang
Chao
C
Wen
Yan
Y
Zhang
Shu-wen
SW
Wang
Bao-en
BE
D000809:Angiotensins / Q000097:blood; D000818:Animals; D004195:Disease Models, Animal; D019446:Endotoxemia / Q000097:blood*; D016753:Interleukin-10 / Q000097:blood; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D000809:Angiotensins; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007703:Peptidyl-Dipeptidase A; D012083:Renin