Chronic renal failure (CRF) is associated with high incidence of cardiovascular complications. To clarify pathogenesis of CRF numerous animal models have been developed. The aim of our work was to describe methodology of subtotal surgical renal ablation in rat and to characterize some biochemical and cardiovascular parameters of this animal model. Male rats underwent 5/6 surgical nephrectomy or sham operations in two steps. The following parameters were measured on day 10 and in week 10 after the surgery: plasma concentrations of creatinine and urea, blood pressure, resting heart rate, chronotropic response to atropine and metipranol, heart ventricles weight, contraction parameters and action potential duration in the left ventricle. Increased serum concentrations of creatinine and urea, decreased creatinine clearance, polyuria and alteration of the remnant kidney tissue were found in CRF rats. Changes in cardiovascular parameters identified after subtotal nephrectomy resembled alterations of cardiovascular system in uremic patients and included hypertension, elevated resting heart rate, diminished parasympathetic cardiac tone, hypertrophy of the left ventricle associated with weakened force of contraction, prolonged contraction and relaxation and shortening of action potential duration. These data suggest that the present model can be a useful tool in the study of CRF and its cardiovascular complications., J. Švíglerová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
This study sought to evaluate whether consumption of polyphenol extract from Cognac (CPC) modulates platelet activation and cardiovascular reactivity in rats. Male Wistar rats were treated daily for 4 weeks by intra-gastric gavage receiving CPC at 80 mg/kg/day or vehicle (5 % glucose). Platelet adhesion and aggregation in response to different activators were assessed. Cardiac and vascular reactivity in response to various agonists as well as NO measurement by electron paramagnetic resonance technique were investigated in isolated heart and thoracic aorta. Oral administration of CPC decreased platelet aggregation induced by ADP but not by collagen. CPC did not affect adhesion to collagen. The chronotropic but not the inotropic response to isoprenaline was reduced without alteration of NO production in hearts from CPC-treated rats. CPC treatment did not affect ex vivo relaxation to acetylcholine nor NO content of rat aorta. CPC did not significantly alter the response to phenylephrine in aorta despite the participation of endothelial vasoconstrictor products. In summary, chronic treatment with CPC has no impact on ex vivo vascular and cardiac reactivity; however, it reduced heart work and platelet aggregation. These data suggest the existence of compounds in Cognac that may decrease the risk of coronary thrombosis and protect against some cardiac diseases., J. Švíglerová, J. Kuncová, L. Nalos, J. Slavíková, M. Štengl., and Obsahuje bibliografii a bibliografické odkazy
Vasoactive intestinal peptide (VIP) is a neuropeptide released from the autonomic nerves exerting multiple antiinflammatory effects. The aim of the present study was to investigate the impact of severe sepsis and hemofiltration in two settings on plasma and tissue concentrations of VIP in a porcine model of sepsis. Thirty-two pigs were di vided into 5 groups: 1) control group; 2) control group with conventional hemofiltration; 3) septic group; 4) septic group with conventional hemofiltration; 5) septic group with high-volume hemofiltration. Sepsis induced by faecal peritonitis continued for 22 hours. Hemofiltration was applied for the last 10 hours. Hemodynamic, inflammatory and oxidative stress parameters (heart rate, mean arterial pressure, cardiac output, systemic vascular resistance, plasma concentrations of tumor necrosis factor- α , interleukin-6, thiobarbituric acid reactive species, nitrate + nitrite, asymmetric dimethylarginine) and the systemic VIP concentrations were measured before faeces inoculation and at 12 and 22 hours of peritonitis. VIP tissue levels were determined in the left ventricle, mesenteric and coronary arteries. Sepsis induced significant increases in VIP concentrations in the plasma and mesenteric artery, but it decreased peptide levels in the coronary artery. Hemofiltration in both settings reduced concentrations of VIP in the mesenteric artery. In severe sepsis, VIP seems to be rapidly depleted from the coronary artery and, on the other hand, upregulated in the mesenteric artery. Hemofiltration in both settings has a tendency to drain away these upregulated tissue stores which could result in the limited secretory capacity of the peptide., J. Kuncová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy