MICROVASCULAR LEAKAGE IN MOUSE PIAL VENULES INDUCED BY BRADYKININ

The actions of bradykinin on pial venule leaky site formation were mea sured intra-vitally in two inbred strains of mice (BALB/c and SJL/J). Pial venules were visualized using an open cranial window microscopy t echnique and the microvascular leaky site formation was assessed visua lly using a fluorescein-dextran (70 kDa) indicator. The SJL/J strain w as found to be very sensitive to bradykinin-induced microvascular leak age. Pial venule leaky site formation was observed after exposure to 1 0 pM of bradykinin. In contrast, the BALB/c strain was found to be ref ractory to bradykinin-induced leakage. Pial arterioles were dilated in response to bradykinin in both strains of mice. These results support the concept that genetically controlled differences in vascular sensi tivity and localization of inflammatory peptides play important roles in the generation of vasogenic oedema and inflammation in CNS trauma a nd disease.