ISSN:
1573-4919
Keywords:
secretory phospholipase A2
;
cytosolic phospholipase A2
;
rat liver
;
septic shock
;
GTP-binding proteins
;
cholera toxin
;
pertussis toxin
;
phospholipid hydrolysis
;
liver metabolism
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract Effects of GTP-binding proteins on the activation of secretory phospholipase A2 (sPLA2) and cytosolic phospholipase A2 (cPLA2) in rat liver during two different phases of sepsis were studied. Sepsis was induced by cecal ligation and puncture (CLP). Experiments were divided into three groups: control, early sepsis, and late sepsis. Early and late sepsis refers to those animals sacrificed at 9 and 18 h, respectively, after CLP. The results show that in the absence of G-protein modulator, hepatic sPLA2 and cPLA2 activities were activated by 40.8-46 and 91.6-105.8%, respectively, during early and late phases of sepsis. GTPγS and fluoroaluminate (A1F4-) stimulated sPLA2 and cPLA2 activities within each experimental group, i.e., control, early sepsis, and late sepsis. The GTPγS and A1F4--stimulated sPLA2 and cPLA2 activities remained significantly elevated during early phase (22.3-65.6% increase) and late phase (32.5-109.1% increase) of sepsis. Further analyses demonstrate that cholera toxin significantly stimulated sPLA2 and cPLA2 activities within each experimental group, and that the cholera toxin stimulated sPLA2 and cPLA2 activities remained significantly higher during early phase (23.5-37%increase) and late phase (56.7-70% increase) of sepsis. In contrast, pertussis toxin significantly inhibited sPLA2 and cPLA2 activities within each experimental group, and that the pertussis toxin-inhibited sPLA2 and cPLA2 activities remained significantly higher in early septic (57-68.5% increase) and late septic (34.6-45.5% increase) experiments. These data demonstrate that cholera toxin-sensitive Gαs and pertussis toxin-sensitive Gαi were both involved in the activation of sPLA2 and cPLA2 activities in rat liver during the progression of sepsis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1006804429027
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