28 research outputs found
Caracterização da resposta nociceptiva de camundongos às endotelinas e da contribuição destes peptídeos na resposta nociceptiva deflagrada por antígeno
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Farmacologia.O presente estudo investigou os efeitos nociceptivo, hiperalgésico e edematogênico de [endotelinas] (ETs) injetadas por via intraplantar na pata de camundongos. Além disso, avaliou a contribuição das ETs endógenas para a [nocicepção] (NOCI) e a [hiperalgesia] (HIPER) desencadeadas por ovoalbumina (OVA) em animais sensibilizados ao antígeno. A HIPER foi avaliada como a potencialização da NOCI induzida por capsaicina. A ET-1 causou efeitos nociceptivo, hiperalgésico e edematogênico dependentes de dose. Estas respostas foram bloqueadas por A-127722.5 ou BQ-123 (antagonistas ETA), mas não por BQ-788 (antagonista ETB). Além disso, sarafotoxina S6c (S6c) e IRL 1620 (agonistas ETB) não deflagram nenhum dos efeitos da ET-1. Porém, o BQ-788 revelou um efeito hiperalgésico à ET-3, e a S6c inibiu a HIPER à ET-1 sem alterar suas ações nociceptiva ou edematogênica. Em outros experimentos, a NOCI induzida por OVA em animais sensibilizados foi reduzida por bosentan (antagonista ETA/ETB), BQ-123 ou A-127722.5, e aumentada por A-192621.1 (antagonista ETB). Finalmente, a HIPER à capsaicina induzida por OVA foi bloqueada por bosentan, A-127722.5 ou A-192621.1. Estes resultados demonstram que as ETs contribuem para efeitos pró-nociceptivos (inclusive alérgico) e edematogênico mediados por receptores ETA em camundongos, enquanto os receptores ETB modulam distintamente estas respostas ao peptídeo
Antimicrobial activity and cellulose acetate membrane characterization with tangerine peel extract (Citrus reticulata) for bio packing
Biopacking material was obtained by incorporating tangerine peel extract (Citrus reticulata) in cellulose acetate (CA) film. The acetate film with tangerine extract was shown to have a homogeneous material characteristic by FTIR and DSC analysis, being reinforced in MEV and MFA, and showed absence of pores in the film with extract. These characteristics justify the reduced water absorption and release of the CA membrane extract. Low water absorption is important for the film to act as a barrier with external environment and the release of the extract was sufficient to prevent the growth of the strains investigated on the sample surface. The introduction of the extract also reduced the tensile strength and deformation of the film. This study showed the good potential of biomass for active bio packing that can gradually replace non-renewable packaging and take advantage of agricultural waste
Hydroalcoholic crude extract of Casearia sylvestris Sw. reduces chronic post-ischemic pain by activation of pro-resolving pathways
Ethnopharmacological relevance
Casearia sylvestris Sw. is widely used in popular medicine to treat conditions associated with pain.
Aim of the study
The present study investigated the influence of hydroalcoholic crude extract of Casearia sylvestris (HCE-CS) and contribution of pro-resolving mediators on mechanical hyperalgesia in a mouse model of chronic post-ischemia pain (CPIP).
Methods and results
Male Swiss mice were subjected to ischemia of the right hind paw (3 h), then reperfusion was allowed. At 10 min, 24 h or 48 h post-ischemia/reperfusion (I/R), different groups of animals were treated with HCE-CS (30 mg/Kg, orally [p.o]), selected agonists at the proresolving receptor ALX/FPR2 (natural molecules like resolvin D1 and lipoxin A4 or the synthetic compound BML-111; 0.1–1 µg/animal) or vehicle (saline, 10 mL/Kg, s.c.), in the absence or presence of the antagonist WRW4 (10 µg, s.c.). Mechanical hyperalgesia (paw withdrawal to von Frey filament) was asseseed together with histological and immunostainning analyses. In these settings, pro-resolving mediators reduced mechanical hyperalgesia and HCE-CS or BML-111 displayed anti-hyperalgesic effects which was markedly attenuated in animals treated with WRW4. ALX/FPR2 expression was raised in skeletal muscle or neutrophils after treatment with HCE-CS or BML-111.
Conclusion
These results reveal significant antihyperalgesic effect of HCE-CS on CPIP, mediated at least in part, by the pathway of resolution of inflammation centred on the axis modulated by ALX/FPR2
Effect of methylprednisolone use on the rotator cuff in rats: biomechanical and histological study
OBJECTIVE: To evaluate the influence of treatment with different doses of methylprednisolone on the mechanical resistance and possible histological alterations of the rotator cuff tendon in rats.METHODS: Male Wistar rats were divided randomly into four treatment groups: sham, vehicle or 0.6 mg/kg or 6.0 mg/kg of methylprednisolone. Changes to mechanical resistance (in N) and histological parameters (fibrillar appearance, presence of collagen, edema and vascular proliferation) of the rotator cuff tendon were evaluated. The analyses were conducted after administration of one treatment (24 h afterwards), two treatments (7 days afterward) or three treatments (14 days afterwards), into the subacromial space.RESULTS: Seven and fourteen days after the treatments were started, it was found that in a dose-dependent manner, methylprednisolone reduced the mechanical resistance of the rotator cuff tendon (p < 0.05 in relation to the vehicle group). Modifications to the histological parameters were observed on the 7th and 14th days after the first infiltration, especially regarding the presence of collagen and vascular proliferation, for the dose of 0.6 mg/kg of methylprednisolone, and also regarding the presence of collagen, edema and vascular proliferation for the dose of 6.0 mg/kg of corticoid.CONCLUSION: The results obtained demonstrated a relationship between methylprednisolone use through infiltration into the subacromial space and reduction of the mechanical resistance of and histological modifications to the rotator cuff tendon in rats
Evaluation of Two Protocols for Analgesia during Total Unilateral Mastectomy in Bitches
Background: Proper evaluation of pain is essential to select effective anesthetic protocols in surgical procedures in animals. Pain assessment can be accomplished during the perioperative period by measuring several physiological parameters, such as heart and respiratory rates. Measuring serum levels of cortisol and glucose is one of the most commonly used methods to assess the effectiveness of protocols for pain control. The aim of this study was to compare two analgesic protocols in dogs undergoing unilateral total mastectomy, a surgery that can cause moderate-to-severe pain in dogs. Materials, Methods & Results: Eighteen female dogs seen at the Veterinary Hospital of the University of Southern Santa Catarina, Brazil, were recruited for this study, without stratification by breed and age, except for brachycephalic breeds. The animals were divided into two groups: 1) FLK group, in which the animals received preoperative ketamine (5 mg/ kg, IM) and midazolam (0.3 mg/kg, IM), an IV bolus of fentanyl (0.004 mg/kg), lidocaine (2 mg/kg) and ketamine (0.5 mg/kg), and then a combination of fentanyl (0.008 mg/kg/h), ketamine (0.6 mg/kg/h) and lidocaine (2 mg/kg/h) diluted in normal saline solution were infused at a rate of 10 mL/kg/h until the end of the surgical procedure; 2) AM group, in which the animals received preoperative morphine (0.5 mg/kg, IM) and acepromazine (0.05 mg/kg, IM). In both groups, anesthesia was induced by using propofol (6 mg/kg, IV) and maintained with isoflurane. Blood samples were collected by jugular venipuncture (4 mL) in the preoperative and postoperative periods to evaluate serum levels of cortisol and glucose. Statistical analysis was carried out using the two-way analysis of variance (ANOVA) for repeated measures, followed by the Tukey test (P < 0.05). Cortisol levels showed no significant difference between pre- and postoperative periods. Glucose levels showed a significant difference between pre- and postoperative periods in the AM group (P = 0.001). The respiratory rate showed a significant difference between groups at 10 (T10) min after induction (P < 0.001). Discussion: In this study, 67% of the experimental animals were mixed-breed dogs. The average weight was 16.9 ± 10.1 kg. The most frequent age group seen at the Veterinary Hospital was 8-10 years, which is in accordance with other published studies on female dogs with mean age of 10 years. The significant difference in the respiratory rate at T10 can be explained by the respiratory depression caused by a bolus administration of fentanyl in the FLK group. Both protocols were similar in this study; however, higher values of cortisol and glucose, even above the physiological reference values, were observed in the AM group as compared to the FLK group. These higher values must be taken into consideration due to their clinical importance, given that consequences of stress include several deleterious effects, such as immunosuppression, delayed wound healing, and acceleration of disease processes. Findings from this study indicate that the use of a multimodal analgesia protocol, such as the one used in the FLK group, is probably the best alternative for patients submitted to unilateral total mastectomy