Alterations of G-protein and adenylate cyclase signaling in rat liver during the progression of sepsis

• Published in: Shock (Augusta, Ga.) Ga.), 1999, Vol.11 (1), p.39-43
• Main Authors: WU, L.-L, DONG, L.-W, LIU, M.-S
• Format: Article
• Language: English
• Subjects: Adenylyl Cyclases - metabolism; Adenylyl Cyclases - physiology; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Biological and medical sciences; Emergency and intensive care: infection, septic shock; GTP-Binding Proteins - metabolism; GTP-Binding Proteins - physiology; Intensive care medicine; Liver - enzymology; Liver - physiopathology; Male; Medical sciences; Rats; Rats, Sprague-Dawley; Sepsis - enzymology; Sepsis - etiology; Signal Transduction - physiology
• ISSN: 1073-2322; 1540-0514
• DOI: 10.1097/00024382-199901000-00006

Changes in the protein level of various subunits of G-protein and the activity of adenylate cyclase in rat liver plasma membranes during different metabolic phases of sepsis were studied. Sepsis was induced by cecal ligation and puncture (CLP). The results show that the protein levels of Galphai-2 and Galphai-3 were unchanged during the early hypermetabolic (hyperglycemic) phase (9 h after CLP), whereas Galphaai-2 and Galphaai-3 were increased by 32.4 and 59.1%, respectively, during the late hypometabolic (hypoglycemic) phase (18 h after CLP) of sepsis. The protein levels of Galphas and Gbeta remained unaltered during both the early and the late phases of sepsis. The activity of adenylate cyclase remained unchanged during the early phase, whereas it was decreased by 26% (p < .05) during the late phase of sepsis. Since the G-protein/adenylate cyclase signaling system mediates hormonal control of hepatic glucose metabolism, the observed increases in the Galphai-2 and Galphai-3 protein levels coupled with a decrease in the activity of adenylate cyclase may contribute to the development of the hypoglycemia during the late stage of sepsis.