Rabbit Muscle Research Articles

Synthetic flavonoid derivatives targeting the glycogen phosphorylase inhibitor site: QM/MM-PBSA motivated synthesis of substituted 5,7-dihydroxyflavones, crystallography, in vitro kinetics and ex-vivo cellular experiments reveal novel potent inhibitors

Glycogen phosphorylase (GP) is an important target for the development of new anti-hyperglycaemic agents. Flavonoids are novel inhibitors of GP, but their mode of action is unspecific in terms of the GP binding sites involved. Towards design of synthetic flavonoid analogues acting specifically at the inhibitor site and to exploit the site’s hydrophobic pocket, chrysin has been employed as a lead compound for the in silico screening of 1169 new analogues with different B ring substitutions. QM/MM-PBSA binding free energy calculations guided the final selection of eight compounds, subsequently synthesised using a Baker-Venkataraman rearrangement-cyclisation approach. Kinetics experiments against rabbit muscle GPa and GPb together with human liver GPa, revealed three of these compounds (11, 20 and 43) among the most potent that bind at the site (Ki s < 4 µM for all three isoforms), and more potent than previously reported natural flavonoid inhibitors. Multiple inhibition studies revealed binding exclusively at the inhibitor site. The binding is synergistic with glucose suggesting that inhibition could be regulated by blood glucose levels and would decrease as normoglycaemia is achieved. Compound 43 was an effective inhibitor of glycogenolysis in hepatocytes (IC50 = 70 µM), further promoting these compounds for optimization of their drug-like potential. X-ray crystallography studies revealed the B-ring interactions responsible for the observed potencies.

Study on the matching feature of current parameters for inducing contraction of orbicularis oris muscle by artificial facial nerve in rabbit with peripheral facial paralysis

Objective: To explore the optimal matching of the current parameters about artificial facial nerve (AFN) for inducing contraction of the orbicularis oris muscle (OOM) in rabbit with peripheral facial paralysis. Methods: According to the combinations of different stimulus parameters, at different time points, we used AFN to induce contraction of the affected side OOM of the paralyzed rabbit in waking state. We recorded the current amplitudes of the threshold stimulation and peak stimulation under each combination, then compared the total charge of the stimulus consumption under different combinations. Results: Compared the total stimulus charge consumption of the AFN threshold stimulation and that in the peak stimulation respectively under different stimulus frequency and pulse width matching combinations, we found that the frequency, the pulse width and the interaction of the frequency and pulse width among different groups could affect the total charge, the differences were statistically significant (P<0.05). Conclusions: When AFN stimulus frequency is 60 Hz and the stimulus pulse width is 100 μs, the output current intensity is relatively lowest and the total consumed charge is the lowest under the premise of effectively inducing the paralytic side OOM contraction. Thus we recommend this stimulus parametric combination as the optimal combination for meeting the low power consumption of AFN.

H/D Exchange Characterization of Silent Coupling: Entropy-Enthalpy Compensation in Allostery

The allosteric coupling constant in K-type allosteric systems is defined as a ratio of the binding of substrate in the absence of effector to the binding of the substrate in the presence of a saturating concentration of effector. As a result, the coupling constant is itself an equilibrium value comprised of a ΔH and a TΔS component. In the scenario in which TΔS completely compensates ΔH, no allosteric influence of effector binding on substrate affinity is observed. However, in this “silent coupling” scenario, the presence of effector causes a change in the ΔH associated with substrate binding. A suggestion has now been made that “silent modulators” are ideal drug leads because they can be modified to act as either allosteric activators or inhibitors. Any attempt to rationally design the effector to be an allosteric activator or inhibitor is likely to be benefitted by knowledge of the mechanism that gives rise to coupling. Hydrogen/deuterium exchange with mass spectrometry detection has now been used to identify regions of proteins that experience conformational and/or dynamic changes in the allosteric regulation. Here, we demonstrate the expected temperature dependence of the allosteric regulation of rabbit muscle pyruvate kinase by Ala to demonstrate that this effector reduces substrate (phosphoenolpyruvate) affinity at 35°C and at 10°C but is silent at intermediate temperatures. We then explore the use of hydrogen/deuterium exchange with mass spectrometry to evaluate the areas of the protein that are modified in the mechanism that gives rise to the silent coupling between Ala and phosphoenolpyruvate. Many of the peptide regions of the protein identified as changing in this silent system (Ala as the effector) were included in changes previously identified for allosteric inhibition by Phe.

Flavonoids Sophoranone Promotes Differentiation of C2C12 and Extraocular Muscle Satellite Cells

Introduction: Paralytic strabismus involves a functional loss of extraocular muscles resulting from muscular or neuronal disorders. Currently, only a limited number of drugs are available for functional repair of extraocular muscles. Here, we investigated the effects of a novel drug, flavonoids sophoranone, on the differentiation of extraocular muscles as assessed in bothin vivo and in vitro models. Materials and Methods: The effect of flavonoids sophoranone on C2C12 cells was examinedin vitro as evaluated with use of apoptosis, reactive oxygen species (ROS), and cell viability assays. Then, both in vivo and in vitro effects of this drug were examined on the differentiation of C2C12 and satellite cells within extraocular muscles in rabbits. For these latter experiments, RT-PCR and Western blot assays were used to determine expression levels of markers for myogenic differentiation. Results: With use of flavonoids sophoranone concentrations ranging from 0 to 10 μM, no effects were observed upon cell apoptosis, ROS, and cell cycle in C2C12 cells. Based on MTT assay results, flavonoids sophoranone was shown to increase C2C12 cell proliferation. Moreover, flavonoids sophoranone promoted the differentiation of C2C12 and satellite cells within extraocular muscles in rabbits, which were verified as based on cell morphology and expression levels of mRNA and protein markers of myogenic differentiation. Finally, flavonoids sophoranone treatment also increased gene expressions of Myh3, Myog, and MCK. Conclusion: The capacity for flavonoids sophoranone to upgrade the differentiation of both C2C12 and satellite cells within extraocular muscles in rabbits at concentrations producing no adverse effects suggest that this drug may provide a safe and effective means to promote repair of damaged extraocular muscles.

The effect of Nannochloropsis oceanica feed inclusion on rabbit muscle proteome

Nannochloropsis oceanica is a microalga, highly concentrated in protein and EPA (eicosapentaenoic acid). It has a recalcitrant cell wall that decreases nutrient digestibility. The objective of this study is to evaluate the effect of Nannochloropsis oceanica feed inclusion on the muscle proteome of fattening rabbits.Twenty rabbits were housed in individual cages for 5 weeks and were fed a control diet (n = 10) and one with 4.45% inclusion of microalga, replacing whole soybean meal (n = 10). After slaughter, samples of gastrocnemius muscle were taken for label-free proteomic analysis.A total of 1497 proteins were identified, 46 with differential abundance. Control rabbits had high abundance of proteins related to protein metabolism, suggesting higher muscle protein turnover. They also had higher abundance of structural proteins, suggesting a less tender meat by comparison with algae-fed rabbits. These had high abundance of proteins related to amino acid catabolism (Phe, Tyr) and synthesis (Gln). In addition, they had high abundance of proteins related to protein breakdown, overall suggesting that more tender meat may result from algae feeding. Biological significanceMicroalgae are interesting feedstuffs particularly from a sustainability point of view. Their use in farm animal diets could simultaneously enhance the nutritional value and quality of meat. However, the biochemical pathways behind such improvement remain uncharacterized, namely in the rabbit species. By using a proteomics approach, this study will enlighten such biochemical pathways and relate them with productive performance parameters. In addition, results reflect some anti-nutritional properties of the recalcitrant cell wall over amino acid digestibility and consequently, its availability for protein synthesis.

Non-linear Scaling of Passive Mechanical Properties in Fibers, Bundles, Fascicles and Whole Rabbit Muscles.

Defining variations in skeletal muscle passive mechanical properties at different size scales ranging from single muscle fibers to whole muscles is required in order to understand passive muscle function. It is also of interest from a muscle structural point-of-view to identify the source(s) of passive tension that function at each scale. Thus, we measured passive mechanical properties of single fibers, fiber bundles, fascicles, and whole muscles in three architecturally diverse muscles from New Zealand White rabbits (n = 6) subjected to linear deformation. Passive modulus was quantified at sarcomere lengths across the muscle’s anatomical range. Titin molecular mass and collagen content were also quantified at each size scale, and whole muscle architectural properties were measured. Passive modulus increased non-linearly from fiber to whole muscle for all three muscles emphasizing extracellular sources of passive tension (p < 0.001), and was different among muscles (p < 0.001), with significant muscle by size-scale interaction, indicating quantitatively different scaling for each muscle (p < 0.001). These findings provide insight into the structural basis of passive tension and suggest that the extracellular matrix (ECM) is the dominant contributor to whole muscle and fascicle passive tension. They also demonstrate that caution should be used when inferring whole muscle properties from reduced muscle size preparations such as muscle biopsies.

Interactome and F-Actin Interaction Analysis of Dictyostelium discoideum Coronin A.

Coronin proteins are evolutionary conserved WD repeat containing proteins that have been proposed to carry out different functions. In Dictyostelium, the short coronin isoform, coronin A, has been implicated in cytoskeletal reorganization, chemotaxis, phagocytosis and the initiation of multicellular development. Generally thought of as modulators of F-actin, coronin A and its mammalian homologs have also been shown to mediate cellular processes in an F-actin-independent manner. Therefore, it remains unclear whether or not coronin A carries out its functions through its capacity to interact with F-actin. Moreover, the interacting partners of coronin A are not known. Here, we analyzed the interactome of coronin A as well as its interaction with F-actin within cells and in vitro. Interactome analysis showed the association with a diverse set of interaction partners, including fimbrin, talin and myosin subunits, with only a transient interaction with the minor actin10 isoform, but not the major form of actin, actin8, which was consistent with the absence of a coronin A-actin interaction as analyzed by co-sedimentation from cells and lysates. In vitro, however, purified coronin A co-precipitated with rabbit muscle F-actin in a coiled-coil-dependent manner. Our results suggest that an in vitro interaction of coronin A and rabbit muscle actin may not reflect the cellular interaction state of coronin A with actin, and that coronin A interacts with diverse proteins in a time-dependent manner.

In Situ Characterization of the Working Stroke of the Slow and Fast Isoforms of Muscle Myosin

Muscle performance depends on the myosin heavy chain (MHC) isoform expressed in the myosin II motor. Stiffness measurements at sarcomere level in skinned fibres from either soleus or psoas muscles of rabbit have recently indicated that the stiffness and the force of the slow myosin isoform (soleus), are three times smaller than those of the fast isoform (psoas) (Percario et al. J Physiol 596:1243, 2018). Here the investigation on the mechano-kinetic features of the two isoforms in situ is extended to the comparison of the size and speed of the working stroke, measured on the isotonic velocity transient elicited by stepwise drops in force of different sizes superimposed on the plateau force (T0) of maximally Ca2+ activated skinned fibres from either muscle (sarcomere length 2.4 μm, temperature 12°C, 4% dextran T-500). The analysis of the early rapid shortening, due to the synchronisation of the working stroke in the attached motors shows that at high load (0.8 T0) the size of the working stroke is smaller in the slow isoform (2 nm) than in the fast isoform (5 nm), while it is similar at low load (7-8 nm at 0.2 T0). The rate of the working stroke increases by ∼6 times with the decrease in load from 0.8 to 0.2 T0, but, at any load, is one order of magnitude slower in the slow isoform than in the fast isoform. A reduced size of the working stroke of the slow isoform, together with the smaller force per motor, opens the question on the mechanism that can explain the high efficiency of the slow muscle with respect to the fast muscle. Supported by MIUR-PRIN 2010R8JK2X and Telethon GGP12282 (Italy).

Detection of Super-Relaxed Myosin in Specific Human Skeletal Muscle Fiber Types

We are studying the super-relaxed state of myosin, with the goal of developing novel therapeutic tools for treatment of contractile and metabolic disorders. In muscle, myosins use the energy from ATP hydrolysis to perform mechanical work during muscle contraction, and to help maintain basal metabolic rate at rest. The myosin super-relaxed state (SRX) in skeletal muscle is hypothesized to play an important role in regulating muscle cell contractility and thermogenesis, yet its physiological role in skeletal muscle remains elusive. The SRX is a biochemical state of myosin with slowed ATP turnover kinetics, due to auto-inhibition of the catalytic domains. Previous work on myosin SRX focused on samples obtained from rabbits and mice. Here, we have used refined quantitative epifluorescence microscopy of fluorescent MANT-ATP to measure single-nucleotide turnover of myosin in skinned skeletal muscle fibers from human donors for the first time. As with most mammalian muscles, the human vastus lateralis is composed of fibers expressing different myosin heavy chain (MHC) isoforms (I, IIA and IIX), which was determined for each fiber tested using gel electrophoresis. Preliminary results show that human skeletal SRX from MHC I fibers have faster ATP turnover compared to MHC II fibers, as previously observed in rabbit muscle fibers. From this work, we are making significant progress toward understanding the biochemical and physiological significance of myosin SRX in human skeletal muscle.

The effect of fish oil, lycopene and organic selenium as feed additives on rabbit meat quality

ABSTRACT The aim of the study was to compare the quality of rabbit meat depending on the type of feed used. The animals were divided into 5 groups of 10 individuals and were fed ad libitum with feed for 55 days. The control group was fed with the addition of sunflower oil (4%), the feed of group FO was enriched with 4% odourless fish oil (FO), the feed of group FOLyc was enriched with 4% FO and 15 ppm lycopene (Lyc), the feed of group ROSe was enriched with 4% FO and selenized yeast (SeY) and the feed of group FOLycSe contained 4% FO, 15 ppm Lyc and SeY. The obtained results showed that the enrichment of feed with fish oil resulted in an increase in the longissimus muscle mass by 7.3%. The feed supplementation with fish oil was beneficial in terms of nutrition due to the increase in the content of polyunsaturated fatty acids. Fat oxidation level, measured in the malondialdehyde test, indicated that the highest level was observed in muscles of rabbits fed diets enriched with only FO. The use of odourless FO in feed adversely affected the sensory quality of meat by increasing the intensity of negative notes like rancid.

Identify the Specificity of Interaction between the Arabidopsis Starch Synthase 4 and the Plastidial Starch Phosphorylase using a Homologous Protein-Animal Rabbit Muscle Phosphorylase a

Identify the Specificity of Interaction between the Arabidopsis Starch Synthase 4 and the Plastidial Starch Phosphorylase using a Homologous Protein-Animal Rabbit Muscle Phosphorylase a

Trace elements transformation in young rabbit muscles

According to scientific publications, transformation of nutrients in the rabbit feed should be studied with regard to rabbit nutritional specifics that is caused by differences of alimentary canal of the species, involving microorganism role in the digestive process. In the experiment, The research considered the transformation of essential micronutrients of feed (Zn, Cu, and Mn) and their concentration in muscle carcasses of rabbits of differentl age and origine, in industrial rabbit production in Prykarpatyia. Feeding norms and nutrient requirements for experimental animals were performed according to rabbit nutrition requirements approved by the VIII International Rabbit Congress (EGRAN tables, 2004). It has been found out that supplying rabbits of different genotypes with the same nutrition affect the retention of studied micronutrients in certain muscles carcasses differently. The experiment demonstrated that the longest back muscle of a 3-month old new hybrid rabbit (NTC) contented the highest amount of zinc and accounted 6.78 � 0.118 mg kg-1 which was by 1.43 mg kg-1 (p =0.001) more than in the rabbits of the local chinchilla (second group). It is proved that the greatest amount of cuprum was concentrated in the hip carcasses of rabbits of the first group (NTC). This rabbit genotype (first group) dominated over the local breed (the second group) regarding this indicator, when the animals were 2 and 3 months old, by 0.15 and 0.49 mg kg-1 respectively (p=0.01). The content of manganese in the muscles of the hips was also higher in the newly-selected three-breed during all the farming period. Thus, at the age of 2 months, rabbits of the first group outweighed their peers in the second group by 6.52 mg kg-1 (p=0.05), at the age of 3 months - by 1.57 mg kg-1 (p=0.01) and at the age of 4 months - by 0.89 mg kg-1 (p0.01). The three-breed rabbit genotype of of the first group was dominated by pure-breed analogues of the second group in terms of weight gain and feed conversion by 7.5 and 3.4% respectively. Due to better transformation of these trace elements, in the body of intensively growing rabbits, the environment is less polluted. The highest concentration of these trace elements was found in the rabbit muscles of both groups in the 3rd month of life. The highest content of the micronutrients studied was observed in the longest and suprascapular muscle of rabbits. The prospects of further research on the study of the transformation of other heavy minerals in industrial cultivation of rabbits has been overviewed.

Bupivacaine Injection in the Extra Ocular Muscle of Rabbits: Analysis of Global and Orbital Layers

ABSTRACT Purpose To verify the cross sectional area (CSA) of fibers positive for myosin type 1 in the global and orbital layers after bupivacaine (BUP) injection in the superior rectus of the right eye of rabbits. Materials and Methods A total of 40 rabbits were studied; 32 specimens received a 0.3 mL injection of BUP at 1.5% in the superior rectus of the right eye and were euthanised after 7, 28, 60 and 92 days. Another eight rabbits were used as the control group. Immunohistochemical analysis was performed using anti-slow myosin (type 1) antibodies. The ImageJ software was used to measure the CSA of the fibers. Six slides were excluded from the analysis. Finally, 7,204 fibers were counted and statistically analysed. Results The mean CSA was 0.040 µm2 for all the studied fibers. For the orbital layer, mean CSA was 0.038 µm2, whereas the global area measured 0.042 µm2. No statistically significant differences were observed when comparing the orbital layer groups. However, when comparing the mean CSA in the global layer of the control group with the 60-day group an increase was found (0.0339 ± 0.0062 versus 0.0503 ± 0.0114; p = .009). Conclusion This study revealed that 60 days after BUP injection, the extra ocular muscle of rabbits presented an increase in the CSA of myosin 1 type fibers in the global layer.

EFFECT OF PLATELET RICH FIBRIN AND MESENCHYMAL STEM CELL ON MYOBLAST AND FIBROBLASTS RATIO IN RABBIT MUSCLE DEFECT

Background: One of the problems in Orthopedics which often results in less satisfactory outcomes is the muscle injuries treatment. This is due to slow healing process and outcome has not been optimal because it produces scar tissue.Purpose: To evaluate effect of platelet rich fibrin and allogenic mesenchymal stem cell on muscle regeneration through comparation of myoblast and fibroblast ratio.Methods: This research is true experimental with randomized pre and post test with control group design. The treatment group included administering allogenic mesenchymal stem cells (MSC), rich fibrin platelets (PRF), and a combination of both. The study subjects were New Zealand White Rabbit which gastrocnemius muscle is incised. Muscle quality evaluation was done in the second and fourth weeks through histology examination in the form of myoblast cell ratio to fibroblast.Results: In the second week evaluation, administering allogenic MSC combined with PRF gave significant results to an increase in myoblast cell ratio to fibroblast. While evaluation of fourth week, giving of three treatment groups gave significant result to myoblast cell ratio to fibroblast.Conclusion: Allogenic MSC administration combined with PRF can improve New Zealand White Rabbit muscle healing quality by histological examination.

Evaluation of the Crushed Sciatic Nerve and Denervated Muscle with Multimodality Ultrasound Techniques: An Animal Study

This study was aimed at evaluating the value of multimodality ultrasound techniques in the detection of crushed sciatic nerve and denervated muscle in rabbits. Fifty healthy male New Zealand white rabbits were randomly divided into five groups (n = 10 in each group): four crushed injury groups at 1, 2, 4 and 8 wk post-sciatic nerve crushed injury, and a control group without crush injury. The crushed sciatic nerve and denervated muscle were measured with conventional ultrasound, shear wave elastography and contrast-enhanced ultrasonography, and the results were compared with the histopathological parameters. The inter- and intra-reader reliability of multimodality ultrasound was assessed with intra-class correlation coefficients. Our results revealed that the sciatic nerve thickened at 2 wk post-crushed injury (p < 0.01), but recovered to almost normal thickness at 8 wk post-injury. Stiffness of the crushed nerve gradually increased (p < 0.01), and intraneural blood volume decreased (area under the curve, peak intensity, time to peak, p < 0.01 each) over time. Histopathological evaluation revealed obvious collagen hyperplasia and poor regenerated microvascular and sparse axonal regeneration and remyelination. Compared with that of the control group, the elastic modulus of the denervated muscle significantly increased (p < 0.05), which may be related to the increased intramuscular collagen (p < 0.01) and decreased muscle fiber cross-sectional area (p < 0.01). There were no significant differences in contrast-enhanced ultrasonography parameters (area under the curve, peak intensity, time to peak) of the denervated muscle between the crush injury groups and the control group (p >0.05). All ultrasound results had excellent inter- and intra-reader consistency (intraclass correlation coefficient >0.80). In conclusion, multimodality ultrasound techniques could provide quantitative information on the morphologic changes, mechanical properties and blood perfusion of crushed nerve and denervated muscle, which may be of great importance in clinical practice.

Productivity, Nutrient Digestibility, Nitrogen Retention, and Meat Quality in Rabbits Fed Diets Supplemented with Sida hermaphrodita.

Simple SummaryAlfalfa is an important forage crop in rabbit nutrition. Despite the numerous advantages of alfalfa, efforts have been made to find its potential substitutes. Virginia fanpetals (Sida hermaphrodita), is yet another potential substitute for alfalfa in animal diets. The aim of this study was to evaluate the efficacy of dehydrated Virginia fanpetals meal as a substitute for dehydrated alfalfa meal in rabbit diets. The results of this study indicated that Virginia fanpetals meal can be included in rabbit diets at up to 20% as a substitute for alfalfa without compromising the production performance of animals, nutrient digestibility, nitrogen retention, carcass quality, or meat quality parameters.Alfalfa (Medicago sativa) is an important forage crop in rabbit nutrition. Despite the numerous advantages of alfalfa, efforts have been made to find its potential substitutes. The aim of this study was to evaluate the efficacy of Sida hermaphrodita meal as a substitute for alfalfa meal in rabbit diets. The experiment was performed on 90 New Zealand White rabbits divided into three groups. DA group was fed a diet containing 20% dehydrated alfalfa. In the DA/DS group, rabbits received a diet containing 10% dehydrated alfalfa and 10% dehydrated Sida. The diet administered to the DS group contained 20% dehydrated Sida. The results of this study indicate that the dietary supplementation with Sida contributed to an increase in the final body weight of rabbits and improved the feed-conversion ratio. Experimental diets had no influence on nutrient digestibility, nitrogen retention, and selected carcass characteristics of rabbits, except for the proportion of the hind part. The content of dry matter, total protein, and monounsaturated fatty acids in the hind leg muscles of rabbits was higher in the DA group than in the experimental groups. The concentrations of saturated fatty acids were higher in the tissues of animals fed diets supplemented with Sida.

Long-Chain n-3 PUFA Content and n-6/n-3 PUFA Ratio in Mammal, Poultry, and Fish Muscles Largely Explain Differential Protein and Lipid Oxidation Profiles Following In Vitro Gastrointestinal Digestion.

Muscle food characteristics (fatty acid profile, heme-Fe, intrinsic antioxidants) that relate to the formation of (patho)physiological oxidation products during gastrointestinal digestion are investigated. Muscles (n = 33) from 18 mammal, poultry, and fish species, of which some are mixed with lard to standardize their fatty acid profile, are digested in vitro. Lipid oxidation is assessed by thiobarbituric reactive substances (TBARS), n-3 PUFA derivative 4-hydroxy-2-hexenal and propanal, n-6 PUFA derivative 4-hydroxy-2-nonenal and hexanal, and protein oxidation by carbonylation. Digests of n-3 PUFA-rich fish demonstrated the highest n-3 PUFA oxidation, whereas digests of various poultry and rabbit muscles showed highest n-6 PUFA oxidation, which correlated significantly with the n-6/n-3 PUFA ratio. Without lard addition, lipid oxidation is significantly higher in chicken and pork loin digests versus beef and deer digests, whereas the opposite occurred when these muscles are mixed with lard. Protein carbonylation correlates significantly with levels of TBARS and the sum of hydroxy-alkenals in digests. The n-6/n-3 PUFA ratio correlates well with the 4-hydroxy-2-nonenal/4-hydroxy-2-hexenal ratio in digests. Muscular fatty acid profiles largely explain type and extent of lipid and protein oxidation during gastrointestinal digestion. Red meat only stimulates oxidation when digested with specific fat sources.

Residues of Diclofenac Sodium in Rabbit Tissues

The current study aimed to determine residues of diclofenac in different rabbit tissues (liver, muscles, kidneys, spleen, heart , lungs) and serum following intramuscular injection of diclofenac. Tissues were extracted and diclofenac residues were assayed using high-performance liquid chromatography (HPLC). A total of twenty healthy male New Zealand White rabbits were classified into two groups; the first group (n=15) was injected with diclofenac for four successive days at dose 1.5mg/kg twice daily , while the second group (n=5) untreated (control). and then samples were collected on the 1st day , 3rd day, 5thday and 7th day. Diclofenac remained within the detectable limit till the 3rd day in most tested tissues, while in muscle and kidney remained till the 5th day following the last dose of drug administration . Therefore, It can be concluded that rabbit muscles and kidney could be consumed safely after the 5th day post treatment with that dose, while, rabbit liver could be consumed safely after the 3rd day post treatment with that dose without any hazards on consumers according to established recommended MRL.

Evaluation of rabbit meat properties as raw material for functional products manufacturing

The research results of the mass yield and composition of the anatomical areas of rabbits carcass, the mechanisms of autolysis of rabbit meat and histomorphological changes during the course of autolysis were presented in the work. The degree of protein digestibility of rabbit muscle tissue was determined. The object of research was the California rabbit carcass. It was established that the process of meat maturing would be completed in 8 hours. Matured meat is characterized by higher nutritional value and quality. The developing in the rabbit carcass processes affect the functional and technological properties of meat during the rigor mortis resolution and at the beginning of the maturing stage. Functional and technological properties are: 53.7% - water-binding capacity and 50.6% - water-holding capacity. 24 hours later after slaughter, the functional and technological properties as a whole increased to 64.1 and 61.7, respectively, which corresponds to 85% of fresh-killed meat. Such indicators of functional and technological properties are due to the high content of high-quality complete proteins. The high digestibility of the protein components of rabbits muscle tissue was observed. The autolysis stages were illustrated by the microstructural and qualitative characteristics of rabbit meat. The deep character of autolytic processes in the longest back muscle 12 hours after rabbit slaughter, which resulted in the formation of physico-chemical, biochemical, organoleptic properties of meat, ensuring products high quality was identified. Less intensive processes took place in the muscle tissue of piriformis muscle, as well as the pre-blade muscle, which was explained by the structure peculiarities of these parts of the muscular system. The research results indicate the prospects of rabbit meat using in functional products manufacturing. The technologies developed allow to take into account preferences and income level of consumers.

Comparative Histological and Immunohistochemical Study on The Effect of Curcumin and Atorvastatin in Induced Atherosclerosis in Aorta and Cardiac Muscle of Male Rabbits

Background: curcumin has many pharmacological effects including antioxidant, anti-inflammation, eliminating free radicals, anti-tumor, lipid regulation and anti-coagulation. Objectives: to compare the histological effects of curcumin and atorvastatin in experimental induced atherosclerosis in the rabbit’s aorta and heart. Subjects and Methodology: thoracic aorta sections were prepared and stained by Hx&E, orcein, Masson's trichrome and immuonohistochemical staning using CD34. Cardiac sections were prepared and stained by Hx&E, Masson's trichrome stain and immuonohistochemical staning using troponin T. Morphometrical study included, the thickness of both tunica intima and media of thoracic aorta , area % of the elastic fibers contents of both tunica intima and media in thorathic aorta, and the area %of the immune reaction of CD34 in thoracic aorta . Results: the atherosclerotic group showed a significant increase in the thickness of both tunicae intima& media when compared with the control group. There was a significant decrease in elastic fibers content and significant increase in the mean area % of the immune reaction of CD34 versus control. In atorvastatin treated group: there was a significant increase in comparison to control group, while there was a significant decrease in comparison to atherosclerotic group. There was significant decrease in elastic fibers content and significant increase in the mean area % of the immune reaction of CD34 in comparison to control group. In curcumin treated group: the thickness of both tunica intima and media showed a significant increase in comparison to control group. Conclusion: curcumin has potential role in treatment of atherosclerosis and myocardial infarction.