Cardiac markers in five different breeds of rabbits (Oryctolagus cuniculus Linnaeus, 1758) used for cardiovascular research

Abstract: Cardiac biomarkers for clinical and experimental heart diseases have previously been evaluated in rabbits. However, several laboratory assays performed and reported with inconsistent results. This study aimed to assess the effects of breed on serum ANP, CRP, and ACE and establish reference interval (RI) for these biomarkers in a large population of healthy rabbits. Ninety-seven adult rabbits from five breeds were included in this study. Assays were performed using specific ELISA commercial kits. The results were statistically analyzed using ANOVA, Tukey test (p<0.05), arithmetic mean, RI of mean, and standard deviation. A significant effect of breed was shown, indicating different RI between breeds for each biomarker. In conclusion, this study demonstrated that breed is an important physiological variable influencing the normal values of cardiac markers in healthy rabbits

Exogenous insulin stimulates glycogen accumulation in Rhipicephalus (Boophilus) microplus embryo cell line BME26 via PI3K/AKT pathway

Ticks are obligatory blood-feeding arthropods and important vectors of both human and animal disease agents. Besides its metabolic role, insulin signaling pathway (ISP) is widely described as crucial for vertebrate and invertebrate embryogenesis, development and cell survival. In such cascade, Phosphatidylinositol 3-OH Kinase (PI3K) is hierarchically located upstream Protein Kinase B (PKB). To study the insulin-triggered pathway and its possible roles during embryogenesis we used a culture of embryonic Rhipicephalus microplus cells (BME26). Exogenous insulin elevated cell glycogen content in the absence of fetal calf serum (FCS) when compared to cells without treatment. Moreover, in the presence of PI3K inhibitors (Wortmannin or LY294002) these effects were blocked. We observed an increase in the relative expression level of PI3K`s regulatory subunit (p85), as determined by qRT-PCR. In the presence of PI3K inhibitors these effects on transcription were also reversed. Additionally, treatment with Wortmannin increased the expression level of the insulin-regulated downstream target glycogen synthase kinase 3 beta (GSK3 beta). The p85 subunit showed elevated transcription levels in ovaries from fully engorged females, but was differentially expressed during tick embryogenesis. These results strongly suggest the presence of an insulin responsive machinery in BME26 cells, and its correlation with carbohydrate/glycogen metabolism also during embryogenesis. (C) 2009 Published by Elsevier Inc