Effect of kallikrein-kinin system activation by factor XII f pretreatment on experimental hemorrhagic shock

Effects of Hageman factor fragment (factor XIIf) administration on shock induction were studied in anesthetized male Wistar rats with hemorrhagic shock. Administration of factor XIIf in non-hemorrhaged rats resulted in an immediate decrease of mean arterial pressure (MAP) for 5 min and in significant increases of blood glucose, lactate and hematocrit (Hct) as well as in a strong tendency for plasma kallikreinogen (KKN) to decrease. At the beginning of bleeding (15 min after factor XIIf administration) MAP has been normalized again. During subsequent hemorrhage pretreated rats showed a sharper decrease in MAP which remained significantly lower up to 25% of estimated blood volume (EBV) and recovered more slowly to normal level after hemorrhage. Blood glucose, lactate and Hct were significantly higher in pretreated animals after hemorrhage of 30% EBV. KKN depicted significant lower values during hemorrhage and in the posthemorrhagic period. Mortality within the observation time increased from 20% (control group) to 60% (pretreated animals). The results demonstrate that prehemorrhagic kallikrein-kinin system (KKS) activation induced an increased severity of shock state with higher mortality.