Healthy Rabbits Research Articles

Urinary Chemistry in Healthy Cross-bred Pet Rabbits (Oryctolagus cuniculus) and Rabbits with Suspected Chronic Kidney Disease

Abstract Renal biomarkers for early detection of decreased kidney function have been extensively studied in dogs and cats, but there is limited research for pet rabbits. Specifically, studies on urinary indices for cross-bred rabbits are scarce. Therefore, this study aimed to assess the potential use of urinalysis in cross-bred pet rabbits. Urine samples from 30 healthy crossbred pet rabbits and 11 rabbits with suspected kidney disease (KD) from three clinics were collected. Reference intervals of urinary indices, including urinary protein, creatinine (uCRE), urinary protein-to-creatinine (UPC) ratio, gamma-glutamyl transferase (uGGT), and uGGT ratio, were established and compared to two published reference intervals (RIs). The results showed that healthy rabbits consistently had low urine protein levels and abnormal UPC ratios, compared to a published study involving only pure-bred rabbits. Rabbits with KD had higher urine protein levels and significantly higher UPC ratio (p<0.001), with 63% having ratios greater than 0.4. Additionally, rabbits with KD showed significantly (p<0.001) lower uCRE levels and urine specific gravity (USG) with elevated uGGT index (p<0.05), compared to the healthy group. Significant differences (p<0.05) were also observed in urine color, turbidity, pH, and positivity of the occult blood by dipstick. This study underscores potential breed-specific variations in urinary protein levels and UPC ratio, as well as highlights the diagnostic potential of USG, UPC ratio, and uGGT index in rabbits with KD. However, the presence of breed-specific variations and technical nuances in laboratory equipment necessitate careful interpretation of results. Therefore, further studies across larger and more diverse rabbit populations are crucial to validate the diagnostic performance of urinary indices in diagnosing KD in rabbits.

Effects of Sedation on Haematological, Biochemical, Coagulation Profile, and Kaolin-Activated Thromboelastography in Rabbits.

Blood sampling and analysis are essential procedures for assessing the health status of exotic pets. While careful manual restraint is generally recommended, sedation may be necessary in specific cases. However, the use of chemical restraint may introduce analytical variations. The aim of this study is to determine the effects of sedation with butorphanol, midazolam, ketamine and dexmedetomidine on haematological, biochemical and coagulation parameters (prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen), as well as thromboelastography in adult healthy New Zealand rabbits (Oryctolagus cuniculus). Two groups of adult New Zealand rabbits, housed under identical conditions and considered healthy based on normal physical examination and unremarkable clinical histories, were included in the study. The non-sedated group comprised ten rabbits, while the sedated group consisted of fifteen. Blood samples were collected via jugular venipuncture, and haematological, biochemical and coagulation profiles were performed. In conclusion, some variation in haematological and biochemical values were observed depending on sex and/or sedation protocols. Sex can influence haematology in terms of haemoglobin concentration, lymphocyte and platelet count; biochemistry in alanine aminotransferase, chloride, gamma-glutamyl transferase, potassium, sodium, calcium, total cholesterol, urea nitrogen, but not in coagulation parameters. Meanwhile, sedation can affect haematology in terms of leucocyte and lymphocyte count and biochemistry in total bilirubin, calcium, total protein, sodium, albumin, glucose, creatinine, phosphorous. Plasma-based coagulation assays showed increased prolongation of aPTT and PT, although these changes do not seem to be clinically relevant. There were no changes observed in thromboelastographic parameters.

Intravitreal melatonin for the prevention of radiation retinopathy: a step beyond bevacizumab

Purpose Intravitreal bevacizumab has been utilized to mitigate radiation retinopathy, yet the potential role of intravitreal melatonin for its prevention remains unexplored. This study aims to evaluate and compare the efficacy of intravitreal melatonin and bevacizumab in preventing radiation retinopathy in an experimental animal model. Materials and methods Twelve healthy male New Zealand white rabbits (n = 24 eyes) received a single 3000 cGy irradiation dose in both eyes. Intravitreal melatonin (100 mcg/kg = 300 mcg/0.05 mL) was administered to the left eyes of six rabbits, and bevacizumab (1.25 mg/0.05 mL) to the left eyes of the remaining six, with sham injections given to the right eyes as controls. Six weeks after irradiation, bilateral enucleation was performed for biochemical and histopathological evaluation. Results Oxidative stress markers did not differ significantly between the groups (p = .827). Both melatonin and bevacizumab treatments markedly reduced axonal damage compared to the sham control group (p < .001). Melatonin also demonstrated a trend toward superior neuroprotective effects relative to bevacizumab, though this difference was not statistically significant (p = .07). Conclusions Intravitreal melatonin demonstrated efficacy comparable to bevacizumab in reducing radiation-induced retinopathy, with an encouraging trend toward enhanced neuroprotection. These findings position melatonin as a potential novel therapeutic for radiation retinopathy prophylaxis. Further research with larger, long-term studies is warranted to validate these results and investigate melatonin’s broader applications in retinal protection.

Experimental study of extracellular vesicle-small intestine submucosa novel biological composite for urethral stricture repair and reconstruction

Background Urethral stricture (US) is a common condition that considerably affects patients’ quality of life. Objectives This study aimed to explore the adoption value of the extracellular vesicle (EV)- small intestinal submucosa (SIS) complex in the repair of USs. Methods EVs were extracted from healthy male New Zealand white rabbits, and SIS was prepared using peracetic acid (PAA) oxidation and decellularization. The morphology and particle size of the prepared EV-SIS complex were evaluated using electron microscopy and qNano nanoparticle analyzer, and the labeled proteins of EVs were detected using Western blot method. EV-SIS the complex was implanted in a rabbit model of US, and urodynamic parameters were assessed. Results The EV-SIS complex displayed a full morphology, intact membrane structure, and uniform particle size. The protein concentration of EVs in the complex was approximately 0.351 µg/µL, with a yield of approximately 1.86 µg/106 cells. The complex exhibited remarkable repair effects in the rabbit model of US, with bladder capacity, maximal urethral pressure, and minimal urethral pressure all markedly superior to those in the US group ( P &lt; 0.05). Conclusion The EV-SIS complex demonstrates potential clinical value in the repair of USs, improving urodynamic parameters, and offering a promising therapeutic option for patients with US.

Dapagliflozin inhibits ferroptosis to improve chronic heart failure by regulating Nrf2/HO-1/GPX4 signaling pathway.

To study the effect of Dapagliflozin on ferroptosis in rabbits with chronic heart failure and to reveal its possible mechanism. Nine healthy adult male New Zealand white rabbits were randomly divided into Sham group (only thorax opening was performed in Sham group, no ascending aorta circumferential ligation was performed), Heart failure group (HF group, ascending aorta circumferential ligation was performed in HF group to establish the animal model of heart failure), and Dapagliflozin group (DAPA group, after the rabbit chronic heart failure model was successfully made in DAPA group). Dapagliflozin was given by force-feeding method. Echocardiography was used to assess cardiac function, HE staining to evaluate pathological changes in the heart, Prussia blue staining to observe iron ions in myocardial tissue, and enzyme-linked immunosorbent assay (ELISA) to determine serum levels of the inflammatory factors interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) at the end of week 12 and/or the end of week 16. The oxidative stress related indexes of malondialdehyde (MDA), superoxide dismutase (SOD) and superoxide dismutase (GSH-Px) in serum were quantitatively analyzed by colorimetry. Protein expression levels of nuclear factor E2-related factor 2(Nrf2), heme oxygenase-1(HO-1), glutathione peroxidase 4(Gpx4) were detected by Western blot. In animals with chronic heart failure, Dapagliflozin improved cardiomyocyte hypertrophy, degeneration and necrosis. Dapagliflozin increased serum GSH-Px and SOD levels and decreased IL-1β, IL-6, TNF-α and MDA levels (P < 0.05) in a rabbit model of heart failure. Dapagliflozin also decreased cardiac iron ion levels and increased Nrf2, HO-1 and GPX4 protein expression. Dapagliflozin can improve heart failure by inhibiting oxidative stress and ferroptosis, and its mechanism may be related to the regulation of Nrf2/HO-1/GPX4 signaling pathway.

Evaluation of Clinical and Hematological Effect of Xylazine-Ketamine and Xylazine-Atropine in Rabbit

This study was conducted to evaluate the clinical and hematological changes during Xylazine-Ketamine (XK) and Xylazine-atropine (XA) anesthesia in rabbits. Ten healthy and well-fed Rabbits of 1.6 to 2.0 kg BW were selected and divided into two groups: Group I (XK) and Group II (XA). Rabbits in Group I (n=5) were anesthetized with a combination of Xylazine HCl @ 5 mg/kg BW (IM) and Ketamine HCl @ 35 mg/kg BW (IM), whereas Xylazine HCl @ 5 mg/kg BW (IM) and Atropine Sulphate @ 0.2 mg/kg BW (IM) were used for anesthesia in Group II (n=5). In both groups, various clinical parameters like heart rate, respiration rate and temperature were collected from the rabbits before induction of anesthetic agents (control) and thereafter on 15, 30, 45, 60,75, and 90 minutes of post-induction and blood parameters at 0 minute and 30 minutes to evaluate hematological changes. In addition, clinical changes in temperature, respiration and heart rate were also assessed in both groups. RBC, Hb, MCV, MCH and MCHC were decreased significantly (p&lt;0.05) in Group I(XK), temperature, respiration and heart rate were decreased significantly (p&lt;0.05) in both groups during the experiment. There were no significant differences in lymphocytes, monocytes, granulocyte, HCT, platelets values from baseline in group I(XK) and Group II(XA). The rabbits recovered from anesthesia uneventfully. This result showed that the combination of Xylazine and Ketamine would give better anesthetic results in terms of clinical and hematological parameter and general anesthesia compare to Xylazine and Atropine in healthy rabbits. Rabbits should be carefully monitored by the veterinarians during surgical interventions to avoid anesthesia-related risks and complications.

Attenuation of Chronic Oxidative Stress-Induced Testicular and Epididymal Dysfunction by Oral Intake of Lepidium meyenii in New Zealand Rabbits.

Lepidium meyenii (Maca) is a plant that has nutritional benefits and increases the effectiveness of male reproduction. In this study, oxidative stress-exposed New Zealand rabbits were used to assess the ameliorative effects of daily Maca ingestion on testicular and epididymal tissues as well as the quality of fresh and frozen/thawed sperm. Twenty-four 40-week-old, healthy New Zealand white male rabbits were divided into four groups. The first group consumed tap water and served as a control. The second group was given 300 mg of Maca daily in capsules. The third group drank water containing hydrogen peroxide (H2O2) at a concentration of 1%. Finally, the fourth group consumed H2O2 and Maca daily. The ejaculate volume, sperm concentration, vitality, motility and velocity of the H2O2 group were considerably lower than those of the other groups. Frozen/thawed spermatozoa showed more dramatic decreases in motility and velocity as a result of H2O2 consumption. The plasma concentrations of testosterone and total antioxidant capacity were also lowest in the H2O2-treated rabbits, while malondialdehyde levels were highest. Exposure to H2O2 increased collagen deposition between ST and epididymal ducts which induced testicular and epididymis fibrosis. In addition, the spermatogenic and epididymal epithelial cells exhibited signs of apoptosis, degeneration, vacuolation and a reduction in height. Maca intake attenuated most of the damaging effects of H2O2 ingestion-induced oxidative stress. Furthermore, H2O2-treated rabbits had modest nuclear androgen receptor positivity, unlike those in the Maca group. The number of Leydig cells significantly increased with daily Maca intake. In conclusion, daily intake of Maca improved reproductive performance and mitigated the damaging effects of oxidative stress on testicular and epididymal functions in New Zealand rabbits.

Evaluation of the Accuracy of FreeStyle Libre 2 for Glucose Monitoring in White New Zealand Rabbits.

Studies are currently being conducted on rabbits requiring serial glucose monitoring. The FreeStyle Libre 2 (FSL2), a serial glucose monitoring device, has been validated in humans, dogs and cats, but not in rabbits. This study aimed to evaluate the accuracy of the FSL2 in rabbits. Six healthy rabbits were used in this study. Interstitial glucose (IG) was measured using the FSL2, and blood glucose (BG) was measured using a portable blood glucose meter (PBGM); their results were compared with those from a clinical chemistry analyser. For the first 3h, IG and BG were measured at 1-h intervals. Subsequently, they were measured every 8h over a 48-h period. Regular insulin 0.2 U/kg was then administered to the rabbits, and IG and BG were measured every 15min over a 90-min period. Before insulin treatment, no measurements fell within the hypoglycaemic range (BG < 100mg/dL). In the euglycaemic range (BG ≥ 100mg/dL), the PBGM and FSL2 showed 85.7% and 23.8% accuracies, respectively. After insulin treatment, the PBGM showed 95.5% and 81.3% accuracies in the hypoglycaemic and euglycaemic ranges, respectively. The FSL2 showed 68.1% and 37.5% accuracies in the hypoglycaemic and euglycaemic ranges, respectively. Parkes consensus error grid analysis showed that the PBGM and FSL2 had 100% agreement for Zones A (no effect on clinical action) and B (altered clinical action unlikely to affect outcome) in rabbits with and without insulin treatment. There was limited agreement between the FSL2 and reference standard BG measurements. However, the FSL2 allows clinically acceptable identification of hypoglycaemic states in rabbits.

Prenatal Histomorphological and Histochemical Study of Stomach in Indigenous Rabbit (Oryctolagus cuniculus)

The present study was designed to investigate the normal histological features of the stomach at the prenatal stage from ten healthy pregnant rabbits at the third period of pregnancy. The stomach appeared as J-shaped situated at the left part of the abdominal cavity. It found in the front part entirely within the rib. The non-glandular region act as a reservoir, the septa prevented ingesta reflux into the esophagus. Histologically the stomach in both periods composed of four tunics', which were mucosa, tunica submucosa, tunica muscularis and tunica serosa. The stomach also has different regions cardiac, fundic and pyloric regions, glands in the cardiac region were coiled branched tubular gland and almost present of the mucous cells with a few chief cells. In the fundic region the glands in this part were long and simple tubular. There are four secretory cell types: mucous cells, chief cells, parietal cells and endocrine cells, glands in the pyloric region were branched coiled tubular glands which opened at the pits of the pyloric part. The mucous-secreting cell always persists, the pyloric sphincter muscle found as thickened muscle in the pyloric duodenal junction. With PAS stain reaction gave a positive reaction for Cardiac and pyloric glands secretion which indicates the present of neutral mucopolysaccharides. In conclusion, it was found that the histomorphological features of the stomach in prenatal period embryos at the third stage of pregnancy of rabbit it was changed according to the age and food intake after birth.

Prognostic Significance of Biointegration at the Optic-Cornea Joint in Keratoprosthesis Implantation.

The purpose of this study was to characterize the morphological and immunological aspects of biointegration at the optic-cornea joint of a second-generation synthetic corneal device. The initial prototype, single-piece optic-skirt configuration, is constructed from compact and flexible perfluoroalkoxy alkane with porous expanded polytetrafluoroethylene (ePTFE) overlying the skirt to allow skirt-cornea biointegration. The second-generation version was modified to add ePTFE around the optic wall to allow optic-cornea biointegration. Initial and amended second-generation devices were implanted into healthy rabbit eyes. Clinical examination, anterior segment optical coherence tomography, light microscopy, and immunofluorescence studies were performed to assess structural integrity and determine molecular signatures indicative of inflammation and tissue remodeling between the 2 prototypes. Recipient eyes with both device versions showed no epithelial defects or tissue retraction at 3 months postoperatively. Optical coherence tomography images demonstrated no appreciable perioptic space with either prototype. Histopathology of the initial device demonstrated lack of stromal adhesion at the optic-cornea joint with epithelium filling the perioptic space. Second-generation devices demonstrated full sealing of the recipient stroma along the optic stem. Although the routine histopathology did not demonstrate inflammatory cells in the recipient cornea with either device, immunohistochemistry stains demonstrated quiescent phenotype of stromal and epithelial cells only in the second-generation devices. Biointegration between the synthetic corneal device and recipient tissue at the optic-cornea joint seems to avert inflammation and may help prevent sterile tissue lysis and prolong retention.

Preparation, Characterization, and in vivo Pharmacokinetics of Innovative Mixed Polymeric Nanomicelles Coated with Hyaluronic Acid as a Retinal Brimonidine-Carrier System

Background: Due to the limited ocular bioavailability, local ocular injections and systemic delivery were used instead of topical application. These alternative approaches were accompanied by numerous disadvantages. Objectives: Create and test mixed polymeric nanomicelles coated with hyaluronic acid as a topical drug carrier for targeted delivery to the vitreous fluid and retina, overcoming the limitations of eye drops. Methods: The thin-film hydration process was utilized to create nanomicelles, and their physical properties were studied. Colored, pigmented, healthy albino rabbits were employed in vivo experiment. Following anesthesia, 35µl of brimonidine nanomicelles and Alphagan® were administered topically. Samples from the vitreous and retina were collected for RP-HPLC analysis. Results: The nanomicelles' physical qualities made them appropriate as a carrier system for the vitreous fluid. They were spherical with a clear appearance and a pharmacological concentration of 97.11%. The particle size range was 134.2nm, with a PDI of 0.2824. The drug entrapment effectiveness was 62.69%, whereas the surface tension was 39.18 mN/m. Their vitreous pharmacokinetics Cmax, Tmax, and AUC0-t were 28.1ng/µl, 2.0min, and 1268.6ng/µl*min, respectively, compared to 5.0ng/µl, 8.0min, and 129.32ng/µl*min for Alphagan eye drops. The retinal pharmacokinetics were 64.9ng/µl, 17.0min, and 18688.04ng/µl*min, respectively, compared to 31.6ng/µl, 30min, and 6377.67ng/µl*min with Alphagan eye drops. Conclusions: Brimonidine nanomicelles coated with hyaluronic acid could be an effective topical drug-carrier method for delivering medications to the vitreous and retina, with higher bioavailability than eye drops.

Design of Highly Adhesive Urchin‐Like Gold Nanostructures for Effective Topical Drug Administration and Symptomatic Relief of Corneal Dryness

Topical instillation of cyclosporin A (an anti‐inflammatory drug) is clinically recommended as the first‐line treatment for dry eye disease. Nevertheless, it suffers from poor ocular drug retention and cannot comprehensively address corneal dryness‐related symptoms such as oxidative stress, angiogenesis, and neurodegeneration. Inspired by nanotechnology‐mediated material/biological interactions, in this study, a highly adhesive metallic nanoplatform with an urchin‐like structure is designed for topical quercetin administration in dry eye therapy. The gold nanostructures with the most pronounced branch lengths exhibit the strongest cytoadhesion and bioadhesion capabilities, which significantly enhance the corneal retention of nano‐urchins by 150‐fold at 7 days post‐instillation compared with smooth‐surfaced gold nanoparticles. In a rabbit model of corneal dryness, topical single‐dose nanoformulation (high quercetin‐functionalized gold nano‐urchins (NU‐Q(H))) demonstrated remarkable efficacy in stimulating tear production (30‐fold improvement), inhibiting inflammatory IL‐6 expression (49‐fold improvement), attenuating pathological angiogenesis (32‐fold improvement), and promoting nerve regeneration (18‐fold improvement) compared to high quercetin‐functionalized gold nanoparticles (NP‐Q(H)). In particular, the integrity of the ocular surface, tear film, and meibomian gland is restored to levels similar to those in healthy rabbits. These findings suggest the promising potential of nanobiomaterial structural engineering in developing highly adhesive metallic nanomedicines as long‐acting eye‐drop formulations for disease treatment applications.

Intratympanic injections made from eutectic liquid (camphor and menthol)-based oil-less emulsions containing morin hydrate-lipoid E80 complex: An approach to augment drug permeation into inner ear region in a healthy rabbit model

Morin hydrate (MH, flavonols of plants, family-Moraceae) promotes inner ear stem cell survival and differentiation process to preserve the healthy hearing function. However, round window membrane (RWM) of inner ear provides a barrier for MH to reach an adequate amount at inner ear region. Since MH possesses a low aqueous solubility (28.72 ± 0.97 μg/ml), intratympanic (IT) injections of camphor-menthol eutectic liquid-based oil-less emulsions containing MH-Lipoid E80 complex was developed to promote MH ferrying action across RWM. At 360 min post-dissolution time point, the MH solution displayed 92.88 ± 6.26 % drug release, but the drug-Lipoid E80 complex-loaded oil-less emulsions showed 58.05 ± 11.62 % only. The MTT assay results indicate the possible non-toxicity of oil-less emulsions to L-929 cells up to 100 μg/ml concentration. Significant differences were seen between the Cmax and AUC0-t values observed at 90 min in the perilymph after the IT injections of MH solution (14.13 ± 0.33 × 103 ng/ml & 429.55 ± 9.20 × 103 ng min/ml) and MH-Lipoid E80 complex-loaded oil-less emulsions (117.93 ± 4.24 × 103 ng/ml & 5529.46 ± 37.65 × 103 ng min/ml) into the healthy albino rabbits. Hence the IT injections of eutectic liquid-based oil-less emulsions could facilitate the drugs crossing over of RWM in the inner ear regions.

Nintedanib alleviates polypropylene mesh-induced adhesion in rabbit ventral herniorrhaphy

Abstract BACKGROUND: Nintedanib (previously known as BBIF 1120) was approved by the United States Food and Drug Administration and European Medical Agency to treat idiopathic lung fibrosis in the year 2014 and 2015, respectively. It is now gaining interest for its anti-fibrotic activity in other organs and disease conditions. Although a surgical mesh is used as a mainstay therapy for herniorrhaphy, postoperative peritoneal adhesion with a polypropylene mesh is a significant drawback. This study aims to assess the efficacy of nintedanib in preventing postoperative adhesion incited with a polypropylene mesh in a rabbit model of ventral hernia. MATERIALS AND METHODS: Ventral hernia was induced surgically in ten adult healthy New Zealand White rabbits of either sex. Hernioplasty was performed with a polypropylene mesh, and the rabbits were randomly allocated into two groups to receive either oral 1 ml sterile water or 100 mg nintedanib in 1 ml of sterile water for 7 days. The adhesion of the implanted mesh with the intra-abdominal organs was assessed clinically, by histological and ultrastructural studies with scanning electron microscopy (SEM) at 30 days postoperatively. RESULTS: All rabbits were clinically healthy for 30 days post-surgery with no complication at the site of surgery. The incidence of peritoneal adhesion and tenacity was less in the nintedanib group versus the control group (P = 0.00105). Histopathological and SEM evaluations also indicated less fibrosis and adhesion in the nintedanib-treated group versus control. CONCLUSION: Our results show successful prevention of mesh-associated adhesion with nintedanib, but further studies on the mechanistic pathway, pharmacokinetics, dose standardization, and evaluation of systemic side effects are warranted.

Detection of Mycoplasma sp using next-generation DNA sequencing is common on nasal swabs from both healthy and unhealthy pet rabbits (Oryctolagus cuniculus).

Upper respiratory infections are a frequent problem in pet rabbits and rodents, and Mycoplasma pulmonis is 1 of the most common causes of respiratory infections in pet rats. M pulmonis was detected in 1967 in laboratory rabbits via culture of the nares and oropharynx, but overall, Mycoplasma is not commonly identified in the upper airway of rabbits. The objective of this study was to compare the prevalence of Mycoplasma sp detection via next-generation DNA sequencing on nasal swabs obtained from healthy and unhealthy rabbits. The results of nasal swabs from both healthy and unhealthy rabbits submitted for next-generation DNA sequencing from January 2022 to February 2023 were reviewed. Data gathered included signalment, whether or not Mycoplasma sp was detected, and the cell count and relative predominance of Mycoplasma sp compared to other organisms. 91 rabbits met the inclusion criteria, of which 49 were healthy and 42 were unhealthy. Overall, 52 of 91 (57.1%) rabbits were positive and 39 of 91 (42.8%) were negative for Mycoplasma sp. Mycoplasma positivity was significantly (P < .001) more common in healthy rabbits (37/49 [75.5%]) compared to unhealthy rabbits (15/42 [35.7%]). The fact that Mycoplasma positivity was common in both groups of rabbits, and particularly common in rabbits without upper respiratory signs, suggests that Mycoplasma may be normal nasal flora in rabbits. Further research is needed to determine whether Mycoplasma could function as an opportunistic pathogen in rabbits.

Effect of mesenchymal stem cell derived from umbilical cord blood on rabbit intrauterine adhesion model

Objective: To investigate the repair effect of human umbilical cord blood mesenchymal stem cells (hUCB-MSC) on endometrium of intrauterine adhesion (IUA) by establishing animal model. Methods: Eighteen healthy female New Zealand white rabbits were divided into a control group, an IUA group and an hUCB-MSC transplantation group according to random number table method. The control group underwent laparotomy only. The IUA group underwent IUA modeling surgery using curettage and lipopolysaccharide (LPS) cotton placed in uterine cavity for double injury. The hUCB-MSC transplantation group received the same IUA modeling surgery followed by multipoint injection of hUCB-MSC suspension (2×106 cells/ml, 500 μl) into the bilateral uterine myometrium one week after surgery. Four weeks after the IUA modeling surgery, the rabbits were euthanized and samples were collected. Hematoxylin and eosin (HE) staining and Masson staining were used to assess the number of endometrial glands and the fibrosis rate. RNA sequencing was performed on the endometrium of the IUA group and hUCB-MSC transplantation group.The mRNA and protein expression of the fibrosis markers [transforming growth factor β1 (TGF-β1) and tissue inhibitors of metalloproteinase 1 (TIMP1)] and RNA sequencing-related parameters were detected by quantitative real-time PCR (qRT-PCR) and Western blot. Results: Compared with the control group, the number of glands in IUA group decreased (26.33±1.53 vs 4.33±1.53, P<0.001), and the fibrosis rate increased (18.01%±2.21% vs 69.55%±2.42%, P<0.001), indicating successful modeling. HE and Masson staining revealed that the number of glands in the hUCB-MSC transplantation group was increased compared with that in IUA group (17.33±2.52 vs 4.33±1.53, P<0.001), and the fibrosis rate decreased (69.55%±2.42% vs 41.55%±1.99%,P=0.001). Western blot analyses of fibrosis-related proteins (TGF-β1 and TIMP1) showed elevated levels of TGF-β1 (0.91±0.05) and TIMP1 (0.99±0.01) proteins in the IUA group compared to control group (0.61±0.04, 0.68±0.07) (P=0.001, 0.015). The hUCB-MSC transplantation group exhibited reduced expression of TGF-β1 (0.69±0.04) and TIMP1 (0.62±0.08) proteins compared to the IUA group (P=0.005, 0.014). Western Blot results related to the PI3K/AKT signaling pathway [phosphorylated phosphatidylinositol 3-kinase (p-PI3K), phosphorylated protein kinase B (p-AKT)] showed that the expression of p-PI3K(1.05±0.05) and p-AKT(1.17±0.06) in the IUA group increased compared to the control group (0.78±0.03, 0.85±0.05) (P=0.002, 0.002). The expression of p-PI3K (0.74±0.02) and p-AKT (0.93±0.04) proteins in the hUCB-MSC transplantation group decreased compared to the IUA group (P=0.003, 0.005). Conclusion: hUCB-MSC can repair the damaged endometrium in rabbit intrauterine adhesion model by increasing the number of endometrial glands and improving its level of fibrosis.

Effectiveness of ultra-/very-high-frequency oscillations combined with helium–oxygen gas mixture in a rabbit model

High-frequency oscillatory ventilation (HFOV) at frequencies of approximately 15 Hz is associated with optimal CO2 excretion. Higher frequencies using a nitrogen–oxygen gas mixture worsen CO2 excretion. An in vitro experiment using HFOV and a helium–oxygen gas mixture showed a significant increase in CO2 transport, which increased with increases in ventilation frequency. We hypothesised that in HFOV, the change in the arterial partial pressure of CO2 (PaCO2) would be greater at frequencies above 15 Hz when combined with helium–oxygen gas mixture administration. We tested this hypothesis in a hypoventilated healthy rabbit model by administering a helium–oxygen gas mixture at 15, 25, 35, and 45 Hz frequencies. One-way repeated measures ANOVA showed a significant decrease in PaCO2 among the four ventilation frequency groups. Post-hoc analysis showed significant differences between 15 and 35 Hz frequencies and between 15 and 45 Hz frequencies. The mean (standard error) decrease of PaCO2 was 10.8 (2.2), 14.1 (2.3), 21.3 (3.3), and 23.1 (2.5) mmHg at 15, 25, 35, and 45 Hz, respectively. Combination therapy of helium–oxygen gas mixture and high-frequency oscillation using ultra/very high frequencies (35–45 Hz) was associated with a greater PaCO2 decrease than that using the standard frequency (15 Hz).

Morphological and Morphometric Parameters of the Liver of Newborn Male Rabbits Alexander

Introduction. At present, the study of age-related issues of the liver structure in animals is one of the most important objectives of morphology, since liver diseases occupy one of the leading places among the nosologies causing death of newborn animals, in particular rabbits. At the same time, although the data on the micromorphological structure of the digestive tract of rabbits is extensive, the data on the age-related anatomy of the liver in the animals under study is scarce in the available literature. The aim of the paper is to determine the morphofunctional features of the liver of newborn male rabbits.Materials and Methods. The objects of the study were newborn male rabbits of the “butterfly” breed (n=9), who had no deviations in development and constitution. To establish the anatomical and topographic features and morphometric parameters of the liver of the animals under study, the standard anatomical dissection, Pirogov's cuts, macromorphometric and statistical research methods were used.Results. It has been established that the liver of newborn male rabbits of “butterfly” breed has segmental nature, the caudate process is large, distinct from the other lobes. The papillary process is oval in shape, poorly developed, adjacent to the lesser curvature of the stomach. The quadrate and right lobes of the liver are well developed, and the left lobes are less developed, which entails the horizontal position of the organ. The ligamentous attachments of the liver are well developed. A round ligament of liver (ligamentum teres hepatis) with fetal hepatic vessels can be distinguished. The linear and weight parameters of the liver are characterised by the small absolute and large relative values. The liver index is inversely proportional to the body weight of an animal and is 5.91.Discussion and Conclusion. The obtained morphological and morphometric data is aimed at establishing the standard liver parameters of the clinically healthy newborn male rabbits of the “butterfly” breed. The liver boundaries have been defined taking into account the length, width, thickness parameters of each lobe separately. The organ topography has been defined including the skeletotopy, holotopy and syntopy of the individual lobes and processes of the liver.

Histological assessment of the effect of ginger on the healing of chemically-induced aphthous ulceration in rabbits

Background: An aphthous ulcer is a painful and recurrent oral mucosal inflammation that is retractable to treatments and resistant to healing. Conventional treatments include a variety of antiseptic, anti-inflammatory, and analgesic therapies, yet their efficacy remains inconsistent. Aim: The present study was conducted in order to evaluate the effects of ginger powder on the healing of chemically-induced aphthous ulcers in rabbits. Methodology: Twelve healthy rabbits were divided into control and ginger-treatment groups. Aphthous ulcers were induced in both groups. The treatment group received ginger powder topically in the socket every 24 h, for 7 days. Subsequently, all animals were sacrificed, and specimens were collected for macroscopic and histological examination. Results: Histological analysis of the ulcer sites on days 3 and 7 post-induction revealed that ginger-treated ulcers exhibited enhanced healing, as evidenced by increased collagen deposition, fibroblast proliferation, and re-epithelialization. Macroscopic observations also confirmed a faster regression of necrotic tissue and a reduced ulcer size in the ginger-treated group (as compared to the control group). Histological analysis has indicated significant differences in inflammation and blood vessel congestion between the two groups, particularly on day 7. Conclusion: The findings of this study reveal that locally applied ginger can enhance the healing in chemically-induced aphthous ulcers in rabbits, which may support its use in clinical practice.

Novel ophthalmic hyaluronic acid-hydrogel with curcumin nanoparticles for enhanced healing of ulcerative keratitis in rabbit model

Corneal ulcers, whether melting or indolent, are common in humans and companion animals. Treatment involves local administration of antibiotic eye drops and corneal healing drugs. Compared to traditional treatments for ulcerative keratitis, herbal medicines offer unique advantages, such as potent anti-inflammatory effects and inhibition of proinflammatory cytokines. Curcumin, extracted from the Curcuma Longa plant, possesses extensive pharmacological properties, such as anti-inflammatory, anti-cancer, and antioxidant properties, and is used in various medicines. In this study, we developed a novel ophthalmic drop hydrogel using a formulation of Curcumin NPs encapsulated with β-cyclodextrin and hyaluronic acid, to accelerate corneal healing and improve the quality of healed structures. The formation of Curcumin NPs into Hyaluronic acid-based hydrogels was characterized by zeta, FTIR, and scanning electron microscope (SEM) analyses. A total of 25 healthy male New Zealand Albino rabbits were experimentally induced with ulcerative keratitis and treated individually with topical medication. Rabbits were divided into five groups. Fluorescein dye staining, corneal clarity score, Schirmer tear test, proinflammatory cytokine measurement, and pathologic factors assessments were used to evaluate the optimised Curcumin NPs with β-cyclodextrin in Hyaluronic acid hydrogel. Our results demonstrated that the optimized Curcumin NPs with β-cyclodextrin in hyaluronic acid hydrogel significantly reduced the frequency of medication administration compared to conventional therapies, enhancing the quality of healed structures and effectively treating ulcerative keratitis. All findings in this study provide new insight into designing and fabricating novel ophthalmic medicine for ulcerative keratitis for topical usage.