Comparison of the effects of two anaesthetic combinations in rabbits on some neutrophil functions in vitro

[EN] Tissue injury during surgery as well as anaesthesia can lead to modulation of neutrophil function. The aim of this study was to assess how two types of anaesthesia, i.e. combination of ketamine/midazolam/propofol (Group I) and ketamine/propofol (Group II) influenced neutrophil function during and 24 h after operation in rabbits. Blood samples were taken prior to anaesthesia, at 30 and 60 min, and 24 h after starting the experiment. At these time points, degranulation and free radical generation were assessed in both groups. After 30 min of anaesthesia, we observed a decrease in elastase release from 50.96±0.71% to 26.52±4.85% in Group I and from 51.00±0.7% to 41.00±5.48% in Group II, respectively. In subsequent measurements, the elastase level increased to values lower than before starting anaesthesia. The myeloperoxidase (MPO) release decreased significantly after 30 min of anaesthesia in Group I, then increased to the value similar to the pre-anaesthetic level after 60 min. MPO level in Group II also decreased after 30 min but to a lesser degree, and then after 1 h MPO slightly exceeded the pre-anaesthetic level. In both groups, 24 h after the start anaesthesia the values obtained decreased, but remained at a level higher than at the time before anaesthesia. We observed a decrease in alkaline phosphatase (ALKP) levels in both studied groups after 30 min of anaesthesia (from 24.77±5.9% to 15.7±2.1% and from 23.6±1.14% to 10.6±0.89%, in Groups I and II, respectively), with a subsequent increase after 60 min. In Group I, we observed a significant (P<0.01) decrease in NO production 30 min after the start of anaesthesia. After increasing to the pre-anaesthetic level, the NO level was almost constant in both subsequent measurements. In Group II, NO level decreased 30 min after the onset of anaesthesia and then increased, reaching a slightly higher level than at the start of anaesthesia. The superoxide generation by neutrophils from rabbits of both groups decreased after 30 min of anaesthesia and then rose. Because the anaesthetic combinations used alter neutrophil function only transiently, both of them would be applied in surgery in rabbits without the risk of disturbance to the healing process.Wessely-Szponder, J.; Szponder, T. (2010). Comparison of the effects of two anaesthetic combinations in rabbits on some neutrophil functions in vitro. World Rabbit Science. 18(3). doi:10.4995/wrs.2010.841418

The influence of porcine cathelicidins on neutrophils isolated from rabbits in the course of bone graft implantation

[EN] Antimicrobial peptides are important elements of host defence because of their direct antimicrobial activity and modulatory role in innate immune response. The purpose of the study was to determine whether porcine peptides PR-39, protegrins (PGs) and low molecular weight extract (LMWE) are able to influence the neutrophil response during bone graft implantation in rabbits. The study was conducted on 10 White New Zealand rabbits and neutrophil activity was assayed on the basis of elastase, myeloperoxidase, and alkaline phosphatase release as well as free radical generation. Our study showed that PR-39 and PGs inhibited enzyme release from neutrophils except for elastase, which is essential in the first phase of injury. Superoxide and nitric oxide generation under the influence of PR-39 and PGs were also decreased. Moreover, we found that unlike separated peptides PR-39 and PGs, LMWE acts proinflammatorily, intensifying the neutrophil secretory response and free radical generation. These results should be taken into account in treatment with natural antimicrobial peptides. The increased neutrophil responses in the first phase of inflammation during surgery may be useful in prevention of infection, but LMWE should not be used in conditions in which excessive neutrophil response is injurious.Wessely-szponder, J.; Szponder, T.; Bobowiec, R.; Smolira, A. (2013). The influence of porcine cathelicidins on neutrophils isolated from rabbits in the course of bone graft implantation. World Rabbit Science. 21(3):175-183. doi:10.4995/wrs.2013.1350.SWORD17518321

Proliferative and oxidative response of hepatocytes (Hep) and hepatic stellate cells (HSC) isolated from rats exposed to ketogenic diet

Ketogenic diet (KD) is considered in the context of its anti-epileptic effects, but its influence on liver dysfunction has not been elucidated yet. The study was aimed to investigate the activity of hepatocytes (Hep) and hepatic stellate cells (HSC) isolated from rats fed with KD, in respect of NO and superoxide generation by these cells as well as their proliferative activity in vitro. We also sought to characterize the plasma FFA profiles in control and ketogenic rats. Hep and HSC were isolated by the collagenase perfusion method and separated by the Percoll gradient centrifugation. After the 4th, 8th and 12th day of incubation, the media were collected for further analysis. NO generation increased within the time of incubation both in Hep and HSC isolated from KD-rats. In HSC group NO production raised significantly from 2.65 ± 0.07 μM/10⁶ cells on 4th day of incubation to 5.49 ± 1.2 μM/10⁶ cells on 12th day of incubation. In respect to O₂-. generation experimental Hep and HSC provide considerably higher quantities of this free radical. until 12th day of incubation (2.5 ± 0.07 and 3.2 ± 0.3 nM/10⁶ cells, respectively). Although KD exerts anti-proliferative effect on hepatocytes, in respect to HSC it intensifies their proliferative activity. Furthermore, as we estimated on the basis of NO and O₂-. generation both Hep and HSC exposed to KD are the source of free radicals

Transport induced inflammatory responses in horses

Deleterious response to road transport is an important problem in equine practice. It determines different physiological, immunological and metabolic changes which lead to increased susceptibility to several disorders such as pneumonia, diarrhea, colics, laminitis, injuries and rhabdomyolisis. The aim of our study was to look for possible relationships between transportation of female young and older horses over a long and short distance and an inflammatory state reflected by an increase of acute phase protein concentration, oxidative stress and muscle injury. The study was conducted on 24 cold-blooded female horses divided into four groups. Six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 550 km, six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 50 km. Plasma and serum were obtained from blood samples taken before transportation (T0), immediately after transportation (T1) and at an abattoir during slaughter (T2). In these samples fibrinogen, MDA, AST and CK were assessed. Fibrinogen increased in all studied groups especially in fillies after long distance transportation, where it reached 205±7.07 mg/dl before transportation, 625±35.35 mg/dl after transportation, and 790±14.14 mg/dl during slaughter. MDA concentrations rose after transportation and reached the maximal level during slaughter. CK activity was more elevated after short transportation in younger horses, whereas initial activity of AST was higher in older horses. We estimated that intensified responses from acute phase, oxidative stress and muscle injury parameters indicated an inflammatory state