Study of Warm Ischemia Followed by Reperfusion on a Lower Limb Model in Rats: Effect of Allopurinol and Streptokinase

Abstract

MC. Study of warm ischemia followed by reperfusion on a lower limb model in rats: effect of allopurinol and streptokinase. Clinics. 2005;60(3):213-20. Prolonged tissue ischemia leads to changes in microcirculation and production of oxygen free radicals. The event eventually responsible for tissue death is the no-reflow phenomenon and its management is a challenge for the surgeon dealing with replantation or transplantation. We introduce a model of warm ischemia and reperfusion of the lower limb of rats with which we studied the effect of allopurinol and streptokinase. METHOD: Section of the lower limb with preservation of vessels and nerves was performed in 110 rats. Femoral vessels clamped for periods of 0, 2, 4, 6, and 8 hours of ischemia were allowed to reperfuse (groups M0, M2, M4, M6, and M8 respectively). Other groups, E1, E2, and E3, received streptokinase, allopurinol, or a combination of the two drugs after 6 hours of ischemia. RESULTS: Viability rates of the ischemic limbs after 7 days were 100% (M0), 80% (M2), 63.6% (M4), 50% (M6), and 20% (M8). In the experimental groups, E1, E2, and E3, viability rates were 67% (E1), 70% (E2), and 70% (E3). Groups M0, M2, M4, M6, and M8 differed among themselves except for groups M4 and M6. Group E1 had a higher rate of limb viability than M6 (control group) but not than M4. Groups E1, E2 and E3 had higher rates of limb viability than M6 but not than M2 or M4. DISCUSSION: The results suggest that increased viability of limbs after 6 hours of ischemia occurs when allopurinol or streptokinase is used. The combination of the two drugs does not appear to produce any additional effect.

Ischemic preconditioning attenuates remote pulmonary inflammatory infiltration of diabetic rats with an intestinal and hepatic ischemia-reperfusion injury

“…During ischemia, free radicals can attract and activate neutrophils, secreting proteolytic enzymes, releasing more free radicals, thrombi in the microcirculation, platelet aggregation and tissue and cellular edema, culminating in the phenomenon of nonreperfusion 9 whose progression causes irreversibility 10 .…”

Estreptoquinase e oxigênio hiperbárico em congestão após reimplante de membro

“…O presente trabalho utilizou um modelo de oclusão venosa após reimplante de membro posterior de ratos. O procedimento cirúrgico constou de amputação parcial mantendo o pedículo vascular e nervoso do membro semelhante ao modelo utilizado por Concannon et al 27 e Cunha et al 21-23 para estudos de isquemia.…”

“…A viabilidade dos membros mostrou-se como resposta do tipo tudo ou nada, como relatada em modelos de reimplantes isquêmicos de membro [21][22][23]27 . A redução gradual e significante das taxas de viabilidade ao longo dos grupos sugere uma curva tempo de oclusão venosa e viabilidade dos membros, tornando o modelo de oclusão venosa confiável.…”

Estudo da ação da estreptoquinase e do alopurinol em retalhos cutâneos em ilha submetidos à isquemia prolongada: estudo experimental em ratos

“…The phenomenon is known nonperfusion, due to microcirculatory thrombosis and not to pedicle thromobosis. 30,31 The epigastric flap was chosen for this study because it has axial blood irrigation through the inferior surface epigastric vessels, easily accessible, as described by Sasaki and Pang, a model widely used in scientific research [10][11][12][13][14][15]37,[39][40][41][42][43] on the subject of ischemia-reperfusion.…”