Zusammenfassung
Thromboxane (Tx) A(2) has been suggested to be involved in the development of sepsis-induced acute kidney injury (AKI). Therefore, we investigated the impact of cyclooxygenase (COX)-1 and COX-2 activity on lipopolysaccharide (LPS)-induced renal TxA(2) formation, and on endotoxemia-induced AKI in mice. Injection of LPS (3 mg/kg ip) decreased glomerular filtration rate (GFR) and the amount of ...
Zusammenfassung
Thromboxane (Tx) A(2) has been suggested to be involved in the development of sepsis-induced acute kidney injury (AKI). Therefore, we investigated the impact of cyclooxygenase (COX)-1 and COX-2 activity on lipopolysaccharide (LPS)-induced renal TxA(2) formation, and on endotoxemia-induced AKI in mice. Injection of LPS (3 mg/kg ip) decreased glomerular filtration rate (GFR) and the amount of thrombocytes to similar to 50% of basal values after 4 h. Plasma and renocortical tissue levels of TxB(2) were increased similar to 10- and 1.7-fold in response to LPS, respectively. The COX-1 inhibitor SC-560 attenuated the LPS-induced fall in GFR and in platelet count to similar to 75% of basal levels. Furthermore, SC-560 abolished the increase in plasma and renocortical tissue levels of TxB(2) in response to LPS. The COX-2 inhibitor SC-236 further enhanced the LPS-induced decrease in GFR to similar to 40% of basal values. SC-236 did not alter thrombocyte levels nor the LPS-induced increase in plasma and renocortical tissue levels of TxB(2). Pretreatment with clopidogrel inhibited the LPS-induced drop in thrombocyte count, but did not attenuate the LPS-induced decrease in GFR and the increase in plasma TxB(2) levels. This study demonstrates that endotoxemia-induced TxA(2) formation depends on the activity of COX-1. Our study further indicates that the COX-1 inhibitor SC-560 has a protective effect on the decrease in renal function in response to endotoxin. Therefore, our data support a role for TxA(2) in the development of AKI in response to LPS.