The aim of study was to review the status of arterial pH, pO2 and pCO2 under general anesthesias in dependence on the light-dark (LD) cycle in spontaneously breathing rats. The experiments were performed using three- to four-month-old pentobarbital(P)-, ketamine/xylazine(K/X)- and zoletil(Z)-anesthetized female Wistar rats after a four-week adaptation to an LD cycle (12 h light:12 h dark). The animals were divided into three experimental groups according to the anesthetic agent used: P (light n=11; dark n=8); K/X (light n=13; dark n=11); and Z (light n=18; dark n=26). pH and blood gases from arterial blood were analyzed. In P anesthesia, LD differences in pH, pO2, and pCO2 were eliminated. In K/X anesthesia, parameters showed significant LD differences. In Z anesthesia, LD differences were detected for pH and pO2 only. Acidosis, hypoxia, and hypercapnia have been reported for all types of anesthesia during the light period. In the dark period, except for P anesthesia, the environment was more stable and values fluctuated within normal ranges. From a chronobiological perspective, P anesthesia was not the most appropriate type of anesthesia in these rat experiments. It eliminated LD differences, and also produced a more acidic environment and more pronounced hypercapnia than K/X and Z anesthesias., P. Svorc, D. Petrášová, P. Svorc Jr., and Obsahuje bibliografii
An oxidant/antioxidant imbalance is thought to play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). We hypothesized that antioxidant capacity reflected by erythrocyte glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) activities, and serum levels of the lipid peroxidation product malondialdehyde (MDA), may be related to the severity of obstructive lung impairment in patients with COPD. Erythrocyte GPx, SOD and CAT activities, and serum levels of MDA were measured in 79 consecutive patients with stable COPD. Pulmonary functional tests were assessed by bodyplethysmography. Moderate COPD (FEV1 50-80 %) was present in 23, and severe COPD (FEV1 < 50 %) in 56 patients. Erythrocyte GPx activity was significantly lower, and serum MDA levels were significantly higher in patients with severe COPD compared to patients with moderate COPD (GPx: 43.1±1.5 vs. 47.7±2.9 U/gHb, p<0.05, MDA: 2.4±0.1 vs. 2.1±0.1 nmol/ml, p<0.05). Linear regression analysis revealed a significant direct relationship between FEV1 and erythrocyte GPx activity (r = 0.234, p<0.05), and a significant inverse relationship between FEV1 and serum MDA levels (r = -0.239, p<0.05). However, no differences were observed in the erythrocyte SOD and CAT activities between the two groups of patients with different severity of COPD. Findings of the present study suggest that antioxidant capacity reflected by erythrocyte GPx activity and serum levels of the lipid peroxidation product MDA are linked to the severity of COPD., Z. Kluchová, D. Petrášová, P. Joppa, Z. Dorková, R. Tkáčová., and Obsahuje bibliografii a bibliografické odkazy