Retrobulbar Plexus Research Articles

Validation of two human point-of-care glucometers for glucose concentration determination in rats

Glucose disorders associated with critical illness are common in veterinary medicine and availability of efficient, easy and affordable diagnostic process is vital in combating the menace. Point-of-care glucometers readily come to mind in achieving this goal considering their importance in research and critical case management in veterinary clinics as they are cheap, user friendly, can use small sample quantity and quick generation of results. However, there have been concerns about generation of erroneous results in certain species. This study compared the accuracy and agreement of two point-of-care glucometers for blood glucose determination in rats. Blood samples were obtained from 20 healthy Sprague-Dawley albino rats. Blood (2 ml) was collected through the retro-bulbar plexus and two glucometers were used to determine the blood glucose concentrations immediately. Thereafter, 1 ml was put into a clean test tube treated with ethylene diamine tetracetic acid and the remaining 1 ml was also put into another test tube without anticoagulant. The samples were processed appropriately to harvest the plasma and serum. Blood glucose test kit was used to measure glucose concentrations in plasma and serum by the glucose oxidase method. Data generated were analysed using one way analysis of variance. Results showed that the mean value generated by one glucometer was relatively comparable with the values generated by the laboratory methods while the other significantly overestimated the glucose concentration. This underscores the importance of validation of glucometers before use in any species as unvalidated glucometers can lead to erroneous research conclusions and clinical decisions with dire consequences

Hepatoprotective activity of a new polyherbal formulation against paracetamol and D-galactosamine induced hepatic toxicity.

Objective:The present study was envisaged to evaluate the protective effect of polyherbal formulation, DRDC/AY/8060, developed by Dabur India Ltd., against paracetamol and D-galactosamine induced hepatic toxicities in Wistar rats.Materials and Methods:The study was carried out in two different experiments of 10 and 14 days against paracetamol and D-galactosamine, respectively. Animals were divided into different treatment groups (n = 6). The control group received normal saline, a toxicant group in two experiments received paracetamol 750 mg/kg p.o. every 72 h for 10 days and D-galactosamine 400 mg/kg i.p. single dose. The test formulation was used at the two dose levels of 120 and 240 mg/kg/day. Treatment groups treated with test formulations were also administered D-galactosamine as given in toxicant group. At the end of the dosing schedule, blood was withdrawn from the retrobulbar plexus of the animals for serum estimation of serum glutamate oxaloacetate transferase (SGOT), serum glutamate pyruvate trasnferase (SGPT), albumin, bilirubin, and alkaline phosphatase (ALP). Following the withdrawal of blood animals was sacrificed, and liver tissue was excised for estimation of thiobarbituric acid reactive substances (lipid peroxidation, malondialdehyde), tissue glutathione (GSH) and histopathological studies.Results:It was evident from the biochemical estimation that both paracetamol and galactosamine caused hepatotoxicity in the toxicant groups. However, treatment with DRDC/AY/8060 significantly (P < 0.001, vs. toxicant) reduced the levels of SGOT, SGPT, serum bilirubin, and ALP, as well as decreased lipid peroxidation. In addition, treatment with test formulation also significantly (P < 0.001, vs. toxicant) elevated serum albumin and GSH levels compared to toxicant groups.Conclusion:On the basis of these studies and comparative evaluation it can be concluded that the formulation DRDC/AY/8060 showed hepatoprotective activity against paracetamol and D-galactosamine at 120 mg/kg and 240 mg/kg.

Allium cepa Linn. (Liliaceae) (red onion) bulb aqueous extract increases membrane stability of red blood cells and ameliorates oxidative stress in diabetes

The aim of this study was to assess the effects of Allium cepa aqueous extract on red blood cell membrane stability and oxidative stress in streptozotocin-induced diabetic Wistar rats. Various alterations of red blood cell (RBC) membrane appear both in diabetes mellitus and during the physiological aging processes. Diabetes mellitus decreases the life span of red blood cells therefore, it may change the membrane stability by acting through its effect on the aging process. Fresh A. cepa bulbs were mashed and macerated in distilled water for 48 h. The freeze dried filtrate (413.7 g) was used for the experiment. Male rats (120–170 g) were made diabetic by a single intraperitoneal injection of streptozotocin (60 mg/kg). Animals with fasting blood sugar (FBS) of 10 mmol/l on day 3 post challenge were selected, grouped, and treated with aqueous extract of A. cepa for 21 days at doses of 50, 150, 300 mg/kg and glibenclamide (2 mg/kg). A negative (challenged and untreated) and a normal control (unchallenged and untreated) groups were included. On day 21, blood samples were collected through the retrobulbar plexus of the medial cantus of the eye for osmotic fragility and in vivo oxidative stress markers analysis. The results showing showed an increase in percent stabilization (through increasing median corpuscular fragility, MCF) with increasing dose of the extract treatment. It also showed an increase in serum catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD) which were significant (p < 0.05) at 150 and 300 mg/kg when compared with the negative control. Malondialdehyde (MDA) was also significantly reduced in these groups with increasing dose of the extract. This study suggests that increase in osmotic fragility of red blood cells attributed to the disturbance in ionic motion through their membrane could be stabilized with aqueous extract of A. cepa. Also, the extract ameliorates oxidation caused by reactive oxygen species and other free radicals produced in diabetic states.

Investigation of the effects of CO2 insufflation on blood gas values during laparoscopic procedures in pigs

Due to the fact that they produce less post-operative pain and shorter hospitalisation times, laparoscopic surgery procedures are more widely used than many traditional open surgical methods. However, the carbon dioxide gas used to visualise the surgical site during the procedure causes complications such as an increase in the blood CO_2 level and acidosis. In the present study, 12 male pigs were used. Sedation was achieved via intramuscular injection of xylazine at a dose of 2 mg/kg and anaesthesia induction was done via slow intravenous injection of ketamine HCl at a dose of 2 mg/kg. Following endotracheal intubation, general anaesthesia was maintained using isoflurane. Blood samples were collected from the retrobulbar plexus immediately before CO_2 pneumoperitoneum (T_0) and 30 min after insufflation (T_1). Cases were evaluated with respect to pH, pCO_2, HCO-_3, and SpO_2 levels. The findings obtained revealed that there was a statistically significant difference between T0 and T1 measurement times with respect to pCO_2 and HCO-_3 although there were no significant differences between the other evaluated parameters. As a result, it has been demonstrated that carbon dioxide pneumoperitoneum in laparoscopic surgery increases blood CO_2 levels. Careful anaesthesia, endotracheal intubation, and 100% O_2 inhalation throughout anaesthesia, however, can compensate for this increase. Consequently, with the preservation of blood pH and the stabilisation of pO_2 levels, laparoscopic interventions can be performed without endangering the patient's life.

Cellular Recognition of Trimyristoylated Peptide or Enterobacterial Lipopolysaccharide via Both TLR2 and TLR4

Evidence for specific and direct bacterial product recognition through toll-like receptors (TLRs) has been emphasized recently. We analyzed lipopeptide analogues and enterobacterial lipopolysaccharide (eLPS) for their potential to activate cells through TLR2 and TLR4. Whereas bacterial protein palmitoylated at its N-terminal cysteine and N-terminal peptides derived thereof are known to induce TLR2-mediated cell activation, a synthetic acylhexapeptide mimicking a bacterial lipoprotein subpopulation for which N-terminal trimyristoylation is characteristic (Myr(3)CSK(4)) activated cells not only through TLR2 but also through TLR4. Conversely, highly purified eLPS triggered cell activation through overexpressed TLR2 in the absence of TLR4 expression if CD14 was coexpressed. Accordingly, TLR2(-/-) macrophages prepared upon gene targeting responded to Myr(3)CSK(4) challenge, whereas TLR2(-/-)/TLR4(d/d) cells were unresponsive. Through interferon-gamma (IFNgamma) priming, macrophages lacking expression of functional TLR4 and/or MD-2 acquired sensitivity to eLPS, whereas TLR2/TLR4 double deficient cells did not. Not only TLR2(-/-) mice but also TLR4(-/-) mice were resistant to Myr(3)CSK(4) challenge-induced fatal shock. d-Galactosamine-sensitized mice expressing defective TLR4 or lacking TLR4 expression acquired susceptibility to eLPS-driven toxemia upon IFNgamma priming, whereas double deficient mice did not. Immunization toward ovalbumin using Myr(3)CSK(4) as adjuvant was ineffective in TLR2(-/-)/TLR4(-/-) mice yet effective in wild-type, TLR2(-/-), or TLR4(-/-) mice as shown by analysis of ovalbumin-specific serum Ig concentration. A compound such as Myr(3)CSK(4) whose stimulatory activity is mediated by both TLR2 and TLR4 might constitute a preferable adjuvant. On the other hand, simultaneous blockage of both of the two TLRs might effectively inhibit infection-induced pathology.

The Determination of Basal Glycemia and Glucose Tolerance Curve: The Manners of Blood Sampling

There were analyzed the conditions under which the basal glycemia and/or glucose tolerance curve is not contaminated by stress induced changes in glycide metabolism. When the basal glycemia was monitored, blood was sampled to heparinized capillaries from retrobulbar plexus under the light ether anaesthesia or by decapitation without narcosis. The animal represented the control for itself. No differences was found in basal glycemia under the two mentioned blood sampling. In the second series of experiments glycemia was monitored in the time schedule which is used in glucose tolerance test, i.e., blood sampling was performed 30, 60, 120 and 180 min after the first sampling from retrobulbar plexus either under light ether anaesthesia (in 14 h starvated rats or in rats with free access to diet) or under Nembutal anaesthesia (in 14 h starvated rats). No differences were found in glycemia when two types of narcosis is compared. No signs of augmentation were detected. In the last series when blood sampling was taken in two sec intervals, time dependent augmentation of stress glucose elevation was found. The augmentation was more expressed in the rats with free access to diet than in starvated animals.

Ambivalent Effect of Long Lasting Terguride Treatment on Genetically Based Glycide and Lipide Metabolism Abnormalities in SHR/N-cp Koletsky Rats

Experiments were carried out in the genetically hypertensive obese rats of Koletsky type (SHR/N-cp obese), in their lean siblings (SHR/N-cp lean) and in the rats of Han-Wistar strain. The effect of long lasting terguride treatment was monitored when the animal represents a control for itself. Blood was sampled to heparinized capillaries from retrobulbar plexus in the same animal before and after the terguride treatment. Long lasting terguride treatment shows decrease in "area under the glucose tolerance curve" in all groups of animals, increase in glycaemia in normotensive males, increase in insulinemia in normotensive rats of both sexes and in SHR/N-cp lean males and decrease of insulinemia in SHR/N-cp obese males, increase of triglyceridemia in normotensive rats of both sexes and in SHR/N-cp lean males, and decrease of triglyceridemia in SHR/N-cp lean females and SHR/N-cp obese of both sexes, increase in cholesterolemia in normotensive and SHR/N-cp lean males, decrease in cholesterolemia in normotensive, SHR/N-cp lean and obese females. Thus ambivalent effect of terguride treatment is more expressive in glucose tolerance and in plasma triglycerides. Ambivalent effect of long lasting terguride treatment is profoundly expressed in correlation between pre-treatment state of individual parameters and the effect of treatment expressed in percentage changes in post-treatment state. In all cases statistically significant correlation coefficients show negative mark. Thus it is apparent that terguride increases monitored parameter when this parameter is low before treatment, and vice versa. When it is considered "area under the glucose tolerance curve", significance was attained in all groups, when judging basal glycaemia, significance was attained in normotensive and SHR/N-cp lean rats of both sexes, taking into account insulinemia, significance was attained in normotensive and SHR/N-cp obese rats of both sexes, when analysing plasma triglycerides, significance was attained in normotensive rats of both sexes and in SHR/n-cp lean females and obese males, when we consider total plasma cholesterol, significance was attained in normotensive rats of both sexes and in SHR/N-cp lean males. From the clinical point of view it must be underlined that terguride is potent to increase insulinemia. Thus there is open a possibility of the other clinical indication of the mentioned drug.