Dexmedetomidine and S(+)-ketamine in ischemia and reperfusion injury in the rat kidney

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Does propofol and isoflurane protect the kidney against ischemia/reperfusion injury during transient hyperglycemia?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atividade colinesterásica cerebral e comportamento de ratos após exposição perinatal ao diclorvós

O organofosforado diclorvós impregnado em coleiras plásticas é um recurso utilizado em medicina veterinária que visa ao controle de ectoparasitas de cães e gatos. O objetivo deste trabalho foi avaliar os efeitos do uso de coleiras plásticas impregnadas com diclorvós (8,37%) em ratas Wistar durante o período de gestação e lactação, como possível fonte de alterações comportamentais e da atividade colinesterásica cerebral dos filhotes. Na desmama, não houve diferença na atividade colinesterásica cerebral entre as mães tratadas com diclorvós e o grupo controle, bem como entre os respectivos filhotes. O tratamento com diclorvós também não influenciou no comportamento geral dos animais, avaliado no campo aberto, nem no nível de ansiedade testado no labirinto em cruz elevado, ambos aos 35 dias pós-natal.

Effects of lisinopril on experimental ischemia in rats. Influence of infarct size

OBJECTIVE - Angiotensin-converting enzyme inhibitors (ACEIs) have gained importance in preventing or attenuating the process of ventricular remodeling after myocardial infarction. The significance of infarct size in regard to the response to ACEIs, however, is controversial. This study aimed to analyze the effects of lisinopril on mortality rate, cardiac function, degree of cardiac hypertrophy and fibrosis in rats with different infarct sizes. METHODS - Lisinopril (20 mg/kg/day) dissolved in drinking water was administered to rats immediately after coronary artery occlusion. After being sacrificed, the infarcted animals were divided into two groups: one group of animals with small infarcts (< 40% of the left ventricle) and another group of animals with large infarcts (> 40% of the left ventricle). RESULTS - The mortality rate was 31.7% in treated rats and 47% in the untreated rats. There was no statistical difference between the groups with small and large infarcts in regard to myocardial concentration of hydroxyproline. In small infarcts, the treatment attenuated the heart dysfunction characterized by lower levels of blood pressure and lower values of the first derivative of pressure and of the negative derivative of pressure. The degree of hypertrophy was also attenuated in small infarcts. In regard to large infarcts, no differences between the groups were observed. CONCLUSION - Treatment with the ACEIs had no effect on mortality rate and on the amount of fibrosis. The protective effect of lisinopril on heart function and on the degree of hypertrophy could only be detected in small infarcts

Safety in road crossing of children with cerebral palsy

Aim: Children with cerebral palsy (CP) are regularly confronted with physical constraints during locomotion. Because abnormalities in motor control are often related to perceptual deficits, the aim of this study was to find out whether children with CP were able to walk across a road as safely as their non-handicapped peers. Method: Ten children with CP and 10 non-handicapped children aged 4-14 y were asked to cross a simulated road if they felt the situation was safe. Results: With respect to safety and accuracy of crossings, the behaviour of children with CP was comparable with that of non-handicapped children. However, a closer examination of children's individual crossing behaviour showed considerable differences within the CP group. In contrast to children with damage to the left hemisphere, children with damage to the right hemisphere made unsafe decisions and did not compensate for them by increasing walking speed.Conclusion: the differences in unsafe behaviour and in the ability to compensate for it within the group of children with CP might be related to damage to specific regions of the brain that are involved in the processing of spatial or temporal information.

FTY720 prevents renal T-Cell infiltration after ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury, a common early feature in renal transplantation, results from both free radical species generation and local inflammatory responses that attract different types of cells. The interaction with infiltrating leukocytes could promote damage and death of resident renal cells contributing to worsening of renal function. It has been shown that depletion of host T cells protects against kidney damage after I/R injury, although the mechanism is not fully understood. FTY720, a synthetic analog of a natural product extracted from Isaria sincclairii has shown modulatory properties in experimental models of autoimmune disease, transplantation, and I/R injury. FTY720 alters lymphocyte responses to chemokine homing signals, thereby decreasing the number of lymphocytes in inflammatory sites. We evaluated renal function in mice at 3, 5, and 7 days after I/R injury in the presence or absence of FTY720 treatment. FTY720 treatment promoted earlier recovery of renal function associated with a lower number of renal-infiltrating lymphocytes. These findings confirm previous results showing a protective effect of FTY720 in I/R injury models.

Investigations on the new free radical scavenger polynitroxyl-albumin to prevent ischemia and reperfusion injury after orthotopic heart transplantation in the pig model

Objective: Nitroxides have strong antioxidant capacity but their effectiveness is limited by their rapid intracellular inactivation. Poly nitroxyl-Albumin (PNA) is capable of regenerating inactivated nitroxide. We tested the effect of PNA against reperfusion injury in heart transplantation. Methods: Pig hearts were transplanted orthotopically. In the control group (n = 9) reperfusion was performed without reperfusion modifications. In the experimental group (n = 10) 1 ml/kg PNA was given before cross-clamp release. Results: Hemodynamic performance was impaired after transplantation in both groups without significant intergroup differences. Plasma malonedialdehyde levels were significantly diminished in the PNA group as compared to the controls. CK-MB levels in both groups were increased within the first 2 h of reperfusion without significant intergroup differences. In contrast, there were found significant higher values of myocardial specific lactate dehydrogenase (LD1) in the controls versus PNA group. Conclusions: PNA was able to reduce lipid peroxidation and attenuate free radical activity. Contractile dysfunction could no be improved, indicating that (a) the radical scavenging effect was to weak or (b) other mechanisms than free oxygen radicals are responsible for myocardial damage in this experimental model. (C) 2001 Elsevier B.V. B.V. All rights reserved.