Role of p38 mitogen-activated protein kinase on renal dysfunction after hemorrhagic shock in rats.

Hemorrhagic shock has been reported to induce renal dysfunction as a consequence of different kinds of local inflammatory response. p38 mitogen-activated protein kinase (MAPK) is a key mediator in organ dysfunction relating to the inflammatory states, and acts as an important mediator in the intracellular signal pathway for proliferation, differentiation, and production of proinflammatory cytokines such as TNF-alpha and IL-1beta. The effect of p38 MAPK on the hemorrhagic damage has not been clearly estimated as yet. In this study, our aim was to evaluate the role of p38 MAPK on the renal damage during the first 5 h after a hemorrhage using a specific inhibitor of p38 MAPK activation, FR167653. p38 MAPK activation increased immediately after a hemorrhage and decreased with time. renal mRNA expression of TNF-alpha and IL-1beta increased, renal dysfunction continued to progress, and histological inflammatory injuries were confirmed after hemorrhagic shock. With the pretreatment of FR167653, all of these hemorrhagic changes were attenuated, although the induction of the primary hypotensive state was confirmed. This study demonstrated that renal p38 MAPK is activated in hemorrhagic shock, promotes the expression of proinflammatory cytokines in the kidney, and consequently develops renal dysfunction. We concluded that p38 MAPK activation is essential in causing renal damage and that the inhibition of p38 MAPK activation blocks the development of the renal dysfunction after hemorrhagic shock.