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Abstract-Apolipoprotein E-deficient (apoE(−/−)) mice fed on Western diet are characterized by increased vascular resistance and atherosclerosis. Previously, we have shown that chronic angiotensin (Ang)(1-7) treatment ameliorates endothelial dysfunction in apoE(−/−) mice. However, the mechanism of Ang(1-7) on vasoconstrictor response to Ang II is unknown. To examine Ang(1-7) function, we used apoE(−/−) and wildtype mice fed on Western diet that were treated via osmotic minipumps either with Ang(1-7) (82 μg/kg per hour) or saline for 6 weeks. We show that Ang II-induced renal pressor response was significantly increased in apoE(−/−) compared with wildtype mice. This apoE(−/−)specific response is attributed to reactive oxygen species-mediated p38 mitogen-activated protein kinase activation and subsequent phosphorylation of myosin light chain (MLC 20 ), causing renal vasoconstriction. Here, we provide evidence that chronic Ang(1-7) treatment attenuated the renal pressor response to Ang II in apoE(−/−) mice to wildtype levels. Ang(1-7) treatment significantly decreased renal inducible nicotinamide adenine dinucleotide phosphate subunit p47phox levels and, thus, reactive oxygen species production that in turn causes decreased p38 mitogenactivated protein kinase activity. The latter has been confirmed by administration of a specific p38 mitogenactivated protein kinase inhibitor SB203580 (5 μmol/L), causing a reduced renal pressor response to Ang II in apoE(−/−) but not in apoE(−/−) mice treated with Ang(1-7). Moreover, Ang(1-7) treatment had no effect in Mas(−/−)/apoE(−/−) doubleknockout mice confirming the specificity of Ang (1-

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Theoretical configurations of meiotic chromosomes of potential hybrids between the different Lepilemur species were examined, and the classification of this genus was reviewed in the light of this information. Among the chromosomal rearrangements that occurred during the chromosomal evolution of the sportive lemurs, only those which would generate a pronounced reproductive barrier were considered in relation to the geographic distribution of this genus. The analysis showed that the pattern of geographic distribution is compatible with the inferred chronological occurrence of these chromosomal rearrangements in the phylogenetic tree of the genus Lepilemur.