Omega-3 fatty acids and docosahexaenoic acid oxymetabolites modulate the inflammatory response of equine recombinant interleukin1ß-stimulated equine synoviocytes.

Omega-3 fatty acid (n-3 PUFA) supplementation may have beneficial effects in certain chronic diseases, potentially including osteoarthritis. Favorable effects are attributed, in part, to downstream pro-resolving oxylipid metabolites. We investigated the role of n-3 PUFA and docosahexaenoic acid (DHA)-derived oxylipids (docosanoids) on equine synoviocyte metabolism. We hypothesized that n-3 PUFA and selected docosanoids would modulate inflammatory mediator gene expression by recombinant equine (re)IL-1ß-stimulated synovial fibroblasts. Synoviocyte monolayer cultures were prepared from grossly normal equine carpal synovium. Cellular incorporation of eicosapentaenoic acid (EPA) and DHA was determined using LC-MS and docosanoid biosynthesis by LC-MS-MS. The influence of n-3 PUFA and docosanoids on osteoarthritis marker gene expression was determined by quantitative real time polymerase chain reaction (qPCR). Synoviocytes incorporated EPA and DHA in significant amounts and DHA treatment augmented the synthesis of several docosanoids. Synoviocyte cultures pre-treated with EPA or DHA followed by reIL-1ß stimulation had significant reductions in expression of ADAMTS4, MMP-1, MMP-13, IL-1ß, IL-6 and COX-2. The docosanoids resolvin D1 and D2, maresin 1 and protectin DX, alone and in combination, abrogated ADAMTS4, MMP-1, MMP-13, and IL-6 gene expression in reIL-1ß-stimulated synoviocytes. Similarly, both resolvins and maresin 1 stifled COX-2 expression. Our results demonstrate that synoviocytes readily incorporate n-3 PUFA. DHA incorporation was sufficient for biosynthesis of significant concentrations of several docosanoids which modulated the synovial inflammatory response in vitro. These data indicate n-3 PUFA supplementation may prove useful in the prevention or treatment of osteoarthritis.

Docosahexaenoic acid-derived oxidized lipid metabolites modulate the inflammatory response of lipolysaccharide-stimulated macrophages.

Docosahexaenoic acid (DHA) supplementation has demonstrated beneficial effects in a number of inflammatory diseases. Increasingly, important contributions to its favorable effects are attributed downstream metabolites called docosanoids. Herein, we investigated the role of DHA-derived oxidized lipid metabolites on inflammatory mediator expression by RAW 264.7 murine macrophages. Specifically, macrophage incorporation of DHA, and the resultant biosynthesis of selected pro-resolving docosanoids was quantified. Docosanoid effects on the expression of selected pro-inflammatory cytokines in LPS-stimulated cultures was determined. Macrophages incorporated DHA in significant amounts. In the presence of DHA macrophages produced statistically significant amounts of several putative pro-resolving docosanoids compared to untreated controls. Among them, resolvins D1 and D2 and maresin 1 abrogated COX-2 and IL-1ß gene expression in LPS-stimulated macrophages. In addition to these mediators, protectin DX inhibited LPS-stimulated macrophage expression of IL-6. Our results demonstrate that macrophages incorporate DHA in quantities sufficient for the biosynthesis of biologically-relevant concentrations of a number of pro-resolving docosanoids, certain of which modulate the inflammatory response of macrophages under conditions mimicking acute inflammation. These data provide further information on the mechanism(s) by which DHA exerts salutary effects on the inflammatory response of macrophages.

Incisional hernia repair in horses: a cadaveric study of endoscopic component separation.

OBJECTIVE: To report a technique for endoscopic component separation in horses and quantify the amount of body wall advancement obtained. STUDY DESIGN: Descriptive study. ANIMALS: Fresh cadaveric horses (n = 14). METHODS: After a preliminary anatomic study, 7 horses had unilateral endoscopic component separation involving transection of the external abdominal oblique fascia lateral to the rectus abdominis muscle. A laparoscope, placed using a balloon dissector, was used to create an intermuscular working space between the external abdominal oblique fascia and internal abdominal oblique muscle. A single instrument portal was created 10-12 cm medial to the laparoscope portal. Laparoscopic scissors were used to transect the external abdominal oblique fascia, lateral to its insertion to the external rectus sheath, from ≈ 20 cm cranial to the costochondral junction to the level of the superficial inguinal ring. Subsequently, a 30 cm ventral median celiotomy was created and the myofascial advancement was quantified at points 10 and 20 cm cranial to the umbilicus. RESULTS: Endoscopic component separation was successfully completed in all horses. Component separation provided a net mean (± SD) abdominal wall advancement of 3.5 ± 1.3 cm and 3.4 ± 0.5 cm, 10 cm, and 20 cm cranial to the umbilicus, respectively. CONCLUSION: Endoscopic component separation in horses is technically feasible but, as conducted, results in modest abdominal wall advancement.

Equine laparoscopy: gonadectomy.

Laparoscopic removal of the gonads from male and female horses is regularly performed for a variety of reasons. In female horses, common indications for ovariectomy include behavioral problems and signs of abdominal pain that are linked to estrus. Another indication is an abnormal, enlarged ovary, typically due to ovarian neoplasia, the most common being granulosa thecal cell tumor. Ovariectomy is also a treatment option for ovarian hematomas and other abnormalities. In addition, ovariectomy is used to sterilize mares intended for artificial insemination or embryo transfer programs.

Nephrectomy via ventral median celiotomy in equids.

OBJECTIVE: To report technique for, and outcome after, nephrectomy through a ventral median celiotomy in equids. STUDY DESIGN: Case series. ANIMALS: Equids with unilateral renal disease (n = 6), aged 2 months to 18 years, weighing 90-434 kg. METHODS: A ventral median celiotomy was used to access the left or right kidney. To facilitate surgical exposure, the small intestine was reflected towards the diaphragm using laparotomy sponges and the ascending colon was exteriorized and in some cases evacuated. The peritoneum over the affected kidney was incised and blunt dissection used to free the kidney from the retroperitoneal fat, then the renal artery, vein, and ureter were isolated and ligated. Abdominal lavage with sterile saline solution was performed before abdominal closure. RESULTS: Four horses, 1 donkey, and 1 mule had unilateral nephrectomy to treat verminous nephritis (1), idiopathic hematuria (1), and ectopic ureter (4). A ventral median approach provided adequate access to the kidney in all 6 cases. Two horses had postoperative complications (peritonitis, chylous abdominal effusion) that resolved with medical therapy. No complications attributable to nephrectomy were reported by the owners upon follow-up 1-8 years after surgery. CONCLUSIONS: A ventral median approach for nephrectomy can be used for unilateral nephrectomy in equids weighing up to 434 kg.

Influence of corticosteroids on interleukin-1ß-stimulated equine chondrocyte gene expression.

OBJECTIVE: To compare the effects of triamcinolone acetonide (TA) and methylprednisolone acetate (MPA) on expression of selected chondrocyte genes in recombinant equine interleukin-1ß (reIL-1ß) stimulated articular cartilage explants. DESIGN: In vitro experiment. ANIMALS: Horses (n = 6). PROCEDURES: Articular cartilage explants from 2- to 3- year-old horses were exposed to reIL-1ß in the presence and absence of TA and MPA at 10(-7) and 10(-6) M. Resting levels of mRNA of anabolic and catabolic genes of chondrocyte origin were quantified using qPCR after 6- and 12-hour incubations. Genes of interest included aggrecan interglobular domain, aggrecan, and collagen II, matrix metalloproteinases 3 and 13 (MMP3, MMP 13), aggrecanase 1, tissue inhibitor of matrix metalloproteinases 1 and 2 (TIMP 1, TIMP 2), BCL 2, vascular endothelial growth factor, and cyclooxygenase 2 (COX 2). RESULTS: IL-1ß significantly influenced the expression of most transcripts. MPA and TA inhibited the induction of MMP 13 at 6 and 12 hours; an effect that was significant at 6 hours with MPA at 10(-7) M and TA at 10(-6) M. Similarly, COX 2 was induced by reIL-1ß and MPA and TA significantly inhibited its upregulation. TIMP 2 expression was reduced by reIL-1ß, an effect that was significantly abrogated by MPA and TA. There were no significant differences observed between glucocorticoids for any gene studied. CONCLUSIONS: No differential effects of MPA or TA on chondrocytic gene expression were identified suggesting that any divergent influences of these glucocorticoids on chondrocyte metabolism are posttranslational.

Equine laparoscopy: equipment and basic principles.

Laparoscopic techniques for veterinary surgery are growing in popularity for the same reason the use of minimally invasive procedures has increased tremendously in human surgery. Compared with open surgery, the benefits of laparoscopic surgery include smaller incisions, reduced postoperative morbidity and pain, shorter hospitalization, a more rapid return to normal activities, and, in some instances, superior access. Laparoscopic surgery is different from open surgery in equipment/instrumentation and psychomotor skills. This first article in a series on equine laparoscopic surgery introduces the necessary equipment and reviews basic techniques (e.g., triangulation, optimal coaxial alignment, ergonomics, instrument use) common to all procedures.

Navicular bursoscopy in the horse: a comparative study.

OBJECTIVES: To compare the proportion of the proximal recess of the navicular bursa that could be examined through a single endoscopic portal and the severity of iatrogenic lesions between conventional and modified approaches. DESIGN: Descriptive study. SAMPLE POPULATION: Equine cadaver forelimbs (n=16). METHODS: Arthroscopic access to the navicular bursa in 1 limb of each pair was by a conventional approach and in the other limb, by a modified approach using sharp dissection through the distal digital flexor sheath, immediately palmar to the T ligament. The time required to access the bursa and the estimated proportion of the navicular bone that could be seen with each approach were recorded. Iatrogenic damage to the navicular bone and the deep digital flexor tendon (DDFT) were quantified. RESULTS: The mean access time to the navicular bursa using the conventional approach was 1.21+/-0.41 minutes compared with 2.09+/-0.86 minutes using the modified technique. The estimated proportions of the bursa visible through a single endoscopic portal using the conventional and modified approaches were 60% and 80%, respectively. Scores for navicular bone (P=.003) and DDFT (P=.012) damage using the conventional approach were significantly higher than those using the modified approach. CONCLUSIONS: A modified, transthecal approach to the navicular bursa under direct observation resulted in significantly less iatrogenic damage than the conventional approach. CLINICAL RELEVANCE: With experience, the modified approach is straightforward, reasonably rapid, and allows near-complete examination of the navicular bursa through a single portal, with minimal iatrogenic damage to the intrabursal structures.

Minimum inhibitory concentration and postantibiotic effect of amikacin for equine isolates of methicillin-resistant Staphylococcus aureus in vitro.

OBJECTIVE: To report the minimum inhibitory concentration (MIC) of amikacin sulfate for equine clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and characterize the initial kill and duration of the postantibiotic effect (PAE) for selected strains. STUDY DESIGN: Experimental study. METHODS: Isolates of MRSA (n=35) had their amikacin MIC determined using the E-test agar diffusion method. Two isolates with MICs>256 microg/mL limit were further characterized using broth macrodilution. Six distinct isolates with amikacin MICs of 32, 48, 128 (2 isolates) and 500 (2 isolates) microg/mL had PAE determinations made over a range of amikacin concentrations from 31.25-1000 microg/mL using standard culture-based techniques. RESULTS: Median MIC of the 35 isolates was 32 microg/mL (range 2 to >256 microg/mL). Mean PAE of selected MRSA strains had an overall mean (all amikacin doses) of 3.43 hours (range 0.10-9.57 hours). PAE for MRSA exposed to amikacin at 1000 microg/mL was 6.18 hours (range 3.30-9.57 hours), significantly longer than that for all other concentrations (P<.0001). There was no statistically significant effect of isolate MIC on PAE. CONCLUSIONS: Isolates had a wide range of MIC; however, growth of all 6 selected strains were inhibited within the range of concentrations tested, including 2 strains with MICs of 500 microg/mL. PAE duration was not influenced by the MIC of amikacin but was significantly longer with treatment at 1000 microg/mL than at lower concentrations. CLINICAL RELEVANCE: Clinical isolates of MRSA are susceptible to amikacin at concentrations achieved by regional perfusion: however, the modest duration of PAE observed suggest that further laboratory and in vivo evaluation be conducted before recommending the technique for clinical use.

Laparoscopic mesh incisional hernioplasty in five horses.

OBJECTIVE: To report a technique for incisional hernioplasty in horses using laparoscopic placement of a prosthetic mesh. STUDY DESIGN: Case series. ANIMALS: Horses (n=5) with ventral median abdominal incisional hernia. METHODS: A telescope and 2 instrument portals were established bilaterally, lateral to and distant from the hernia margins. After exposure of the internal rectus sheath by removal of retroperitoneal fat with endoscopic scissors and monopolar cautery, a prosthetic mesh was introduced into the abdomen and secured intraperitoneally using transfascial sutures with or without supplemental endoscopic hernia fixation devices. RESULTS: Successful placement of the prostheses was achieved without major intra- or postoperative complications. Repairs were intact in all horses (follow-up range: 6-23 months) without evidence of adhesion formation. Cosmetic results compared favorably with those typically achieved using conventional, open hernioplasty techniques. CONCLUSION: Incisional hernia repair in horses can be successfully achieved with a laparoscopic intraperitoneal mesh onlay technique. CLINICAL RELEVANCE: Laparoscopic mesh hernioplasty has promise as a safe and effective method for repair of incisional hernias in horses.

Intracorporeal suture closure of the internal inguinal and vaginal rings in foals and horses.

OBJECTIVE: To report a technique for repair or prevention of inguinal hernia in horses using intracorporeal suture closure of the internal inguinal and vaginal rings. STUDY DESIGN: Case series. ANIMALS: Foals (n=6) and geldings (n=2). METHODS: After selection of a peri-umbilical telescope portal, instrument portals were made unilaterally or bilaterally, as needed. Herniated viscera was reduced, castration (foals) or spermatic cord remnant transection at the internal inguinal ring (adults) performed, and then simple interrupted intracorporeal sutures of synthetic absorbable suture material were used to close the internal inguinal and vaginal rings. RESULTS: There was no recurrence of inguinal hernia. Postoperative morbidity was minimal and cosmetic outcome was comparable to that achieved with conventional, open techniques. CONCLUSION: Laparoscopic, primary closure of the internal inguinal ring by use of intracorporeal sutures provides a secure barrier to herniation and costs considerably less than using endoscopic staples. CLINICAL RELEVANCE: Laparoscopic suture closure of the internal inguinal and vaginal rings provides safe and effective repair of inguinal hernia in horses.

Lack of systemic absorption of lidocaine from 5% patches placed on horses.

OBJECTIVE: To measure concentrations of lidocaine serum after application of two 5% patches on horses. STUDY DESIGN: Prospective experimental trial ANIMALS: Six client-owned, systemically healthy horses. METHODS: The hair was clipped on the medial aspect above the carpus of both fore limbs and 2 patches of 5% lidocaine were applied within 30 minutes of jugular catheter placement and the area was then bandaged. Venous blood was drawn from a jugular vein catheter that was inserted using lidocaine as a local block. Samples were drawn immediately before and at 2, 4, 6, 8, and 12 hours after patch application. The presence of lidocaine in serum was determined using an ELISA test. RESULTS: Lidocaine was detected in the serum of three horses at 0 hours immediately following the local block for catheter placement. Lidocaine was not detected at any other time from 2 to 12 hours. There was mild erythema at the site of patch placement at 12 hours in one horse but this resolved within 1 hour of patch removal. There were no other apparent adverse effects from the patches on any other horse. CONCLUSION: Five percent lidocaine patches applied proximally to the carpus did not result in detectable systemic concentrations of lidocaine. CLINICAL RELEVANCE: Any analgesic effects that might be produced by application of 5% lidocaine patches on horses will not be due to systemic absorption of the drug.

Effects of glucosamine and chondroitin sulfate on bovine cartilage explants under long-term culture conditions.

OBJECTIVE: To determine effects of glucosamine (GLN) and chondroitin sulfate (CS) on expression of genes encoding putative mediators of osteoarthritis in bovine cartilage explants cultured for 2 weeks. SAMPLE POPULATION: Articular cartilage explants harvested from carpal joints of 4 Holstein steers after slaughter. PROCEDURES: Cartilage disks were treated as follows: fetal bovine serum only (control treatment), human recombinant interleukin (IL)-1beta (50 ng/mL; IL-1 treatment), GLN (5 microg/mL) with addition of CS (20 microg/mL; GLN-CS treatment), and human recombinant IL-1beta (50 ng/mL) with addition of GLN and CS (IL-1-GLN-CS treatment). Media were analyzed for nitric oxide and prostaglandin E(2) (PGE(2)) release. Explants were subjected to quantitative real-time PCR analysis; expressions of mRNA for inducible nitric oxide synthase, cyclooxygenase-2, microsomal prostaglandin E synthase 1, matrix metalloproteinase (MMP)-3 and -13, aggrecanase-1 and -2, tissue inhibitor of metalloproteinase (TIMP)-3, type II collagen, and aggrecan were assessed. RESULTS: IL-1-GLN-CS and GLN-CS treatments decreased nitrite release, compared with IL-1 treatment; IL-1-GLN-CS treatment decreased IL-1-induced PGE(2) release. Expressions of inducible nitric oxide synthase, cyclooxygenase-2, and microsomal prostaglandin E synthase 1 mRNA were abrogated by GLN-CS and IL-1-GLN-CS treatments. Interleukin-1-induced mRNA expressions of proteolytic enzymes were diminished by IL-1-GLN-CS treatment. Compared with control treatment, GLN-CS treatment decreased MMP-3 and aggrecanase-2 mRNA expression. Transcripts of TIMP-3 were increased by IL-1-GLN-CS treatment, compared with IL-1 treatment. Genes encoding type II collagen and aggrecan on day 14 were upregulated by GLN-CS and IL-1-GLN-CS treatments, compared with control treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with GLN and CS consistently downregulated mRNA expression for inflammatory mediators and matrix degrading enzymes while increasing TIMP-3 transcripts.

Septic osteitis of the distal phalanx in foals: 22 cases (1995-2002).

OBJECTIVE: To determine the clinical characteristics and outcome of foals with septic osteitis of the distal phalanx. DESIGN: Retrospective case series. ANIMALS: 22 foals. PROCEDURES: Information obtained from medical records included signalment; clinical, laboratory, and radiographic findings; treatment method; and outcome. Foals included in the study had lameness referable to the foot, radiographic evidence of localized lysis or focal loss of bone density of the distal phalanx, and suppurative discharge or necrosis of the affected bone evident at surgery. Foals with a history or evidence of penetrating wounds or subsolar abscessation were excluded. RESULTS: Mean age of foals at initial evaluation was 40.8 days (range, 3 to 122 days). Twenty-one (95%) foals had lameness as the primary complaint. Lesions consistent with septic osteitis of the distal phalanx localized to specific areas of the bone on the basis of radiographic and surgical findings were located on the solar margin or toe (14/22 [64%]), extensor process (5/22 [23%]), and palmar or plantar process (3/22 [13%]). Hind limbs (18/26 [69%] affected limbs) were more frequently affected. Two foals had > 1 affected limb, 2 had additional sites of osteomyelitis, and 4 had concurrent septic arthritis. Surgical debridement and regional antimicrobial perfusion were performed during general anesthesia. Extensor process lesions were not debrided. Nineteen of 22 (86%) foals survived to be discharged from hospital, and 16 horses reached racing age. Eleven of 16 had race starts, of which 8 had official race starts and 3 had unofficial race starts. CONCLUSIONS AND CLINICAL RELEVANCE: Septic osteitis of the distal phalanx should be considered as a source of lameness in foals with signs referable to the foot and does not necessarily preclude a career in racing. Although infection may occur secondary to bacterial penetration of the hoof or sole, the distal phalanx should also be considered as a potential site for hematogenous septic arthritis or osteomyelitis in foals.

Cricothyroid muscle function and vocal fold stability in exercising horses.

OBJECTIVES: To determine (1) if the cricothyroid muscle had respiratory-related electromyographic (EMG) activity that increased with respiratory effort and (2) if bilateral cricothyroid myotomy resulted in vocal fold instability and collapse in exercising horses. STUDY DESIGN: Experimental. ANIMALS: Seven (3 EMG; 4 cricothyroid myotomy) Standardbred horses. METHODS: Three horses exercised on a treadmill at speeds corresponding to the speed that produced maximum heart rate (HR(max)), 75% of maximum heart rate (HR(75%max)), and 50% of maximum heart rate (HR(50%max)) for 60 seconds at each speed while EMG activity of the cricothyroid muscle and nasopharyngeal pressures were measured. Another 4 normal horses were exercised on the treadmill at HR(max) and HR(75%max) for 60 seconds at each speed before and after bilateral cricothyroid myotomy. Upper airway pressures were measured and videoendoscopic examinations were performed and videotaped at each speed. RESULTS: Peak phasic EMBG activity of the cricothyroid muscle was coincident with inspiration and increased with treadmill speed. Bilateral cricothyroid myotomy resulted in vocal fold collapse in all horses. Mean peak inspiratory pressures were significantly more negative compared with control values at both HR(max) and HR(75%max). CONCLUSIONS: Cricothyroid muscle dysfunction may be implicated in vocal fold collapse and likely causes inspiratory airway obstruction in exercising horses. CLINICAL RELEVANCE: Conditions compromising cricothyroid muscle function or motor innervation could result in vocal fold collapse.

The prevalence of laryngeal disease in a large population of competition draft horses.

OBJECTIVES: (1) To determine the effect of age, height, weight, breed, sex, and specific use on the prevalence of idiopathic left laryngeal hemiplegia (ILH) in a population of draft performance horses; (2) to determine the association between tracheal mucus and laryngeal dysfunction, and the prevalence of exercise-induced pulmonary hemorrhage (EIPH) in a population of draft performance horses. STUDY DESIGN: Cross-sectional. ANIMALS: Draft horses competing at the 2005 Michigan Great Lakes Draft Horse Show. METHODS: Endoscopic examinations were performed on horses competing at the 2005 Michigan Great Lakes Draft Horse Show. Signalment, height, and weight were obtained from the owners and trainers. RESULTS: Belgian, Percheron, and Clydesdale horses (n=183) were studied. Prevalence of ILH was 35%. Horse height was significantly associated with the risk of ILH in Belgian and Percheron horses but not Clydesdales. There was a significantly different prevalence of ILH among the breeds such that 42% Belgians, 31% Percherons, and 17% Clydesdales were affected. Laryngeal disease was a risk factor for increased tracheal mucus. None of the horses had acute evidence of EIPH. CONCLUSIONS: The prevalence of ILH in draft horses has increased or is higher in competition horses compared with previously studied groups. Tracheal and/or pulmonary inflammation may be more common in draft horses with ILH based on our findings that horses with ILH have more tracheal mucus than horses with normal laryngeal function. CLINICAL RELEVANCE: Selection pressure for large, taller, longer-necked horses may be responsible for a seemingly increased incidence of ILH in competitive draft horses.

Short-term gene expression changes in cartilage explants stimulated with interleukin beta plus glucosamine and chondroitin sulfate.

OBJECTIVE: To determine the short-term effects of glucosamine (GLN) and chondroitin sulfate (CS) on expression of genes encoding inflammatory mediators and matrix enzymes in bovine cartilage explants stimulated with interleukin 1 (IL-1). METHODS: Dose-response experiments were conducted for IL-1, GLN, and CS to select concentrations of each optimized for detecting treatment effects on cartilage explants. Based on the dose-response experiments, treatments included fetal bovine serum (FBS) control, 15 ng/ml IL-1, and 15 ng/ml IL-1 with the addition of 10 microg/ml GLN and 20 microg/ml CS. Media were measured for nitric oxide (NO) and prostaglandin E2 (PGE2) while explants were frozen for RNA extraction at 8, 16, and 24 hours. Gene expression relative to FBS control for inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), microsomal PGE synthase-1 (mPGEs1), nuclear factor-kB p65 subunit (NF-kB), matrix metalloproteinase (MMP)-3 and 13, aggrecanase (Agg)-1 and 2, and tissue inhibitor of metalloproteinase-3 (TIMP-3) were assessed by quantitative real-time polymerase chain reaction (RT-PCR). In a separate study using incubation of explants with the same treatments for 48 hours, proteoglycan release was measured with dimethylmethylene blue assay and TIMP-3 protein was evaluated with Western blots. RESULTS: The GLN and CS combination abrogated IL-1-induced gene expression of iNOS, COX-2, mPGEs1, and NF-kB at all timepoints. NO, PGE2, and proteoglycan release were reduced with the combination. The abundance of stimulated MMP-13, Agg-1, and Agg-2 mRNA was repressed, whereas TIMP-3 was upregulated by the combination at all timepoints. The abundance of TIMP-3 protein was increased by the combination relative to IL-1 at 48 hours. CONCLUSION: GLN and CS in combination suppress synthesis and expression of genes encoding inflammatory mediators and proteolytic enzymes while upregulating TIMP-3. This provides a plausible mechanism for the purported mild antiinflammatory and chondroprotective properties of GLN and CS.

Investigation of the immediate analgesic effects of extracorporeal shock wave therapy for treatment of navicular disease in horses.

OBJECTIVES: To measure the acute analgesic properties of extracorporeal shock wave therapy (ESWT) in horses with navicular disease using objective ground reaction forces (GRF). STUDY DESIGN: Prospective study. ANIMALS: Nine client-owned horses with unilateral forelimb lameness caused by navicular disease. METHODS: Horses were trotted at 3 m/s over a force plate to record pre-treatment GRF of the lame and contra-lateral forelimbs. After ESWT of the lame limb, applied with a radial unit to each of the frog and heel bulb areas with 1500 pulses at 4 bar and 10 Hz, GRF measurements were repeated at 15 minutes and 24-hour intervals for 7 days. From the 5 trials recorded at each time, peak vertical force (PVF) was calculated and averaged. Data were compared between limbs and over time using a 2-way repeated-measures ANOVA. RESULTS: Mean (+/-SD) PVF was significantly different between lame (day 1; 4339+/-626 N) and contra-lateral (day 1; 5236+/-515 N) limbs pre-treatment (P<.05). After ESWT treatment, this difference remained unchanged at 15 minutes and from days 1 to 7. To confirm navicular disease, palmar digital analgesia significantly reduced the lameness (lame 5144+/-430 N; contralateral 5082+/-586 N; P>.05). CONCLUSIONS: Single ESWT treatment applied in this manner does not influence lameness in horses with navicular disease. CLINICAL RELEVANCE: Although many equine regulatory commissions currently ban the use of ESWT before competition, our results suggest that such regulations may be unfounded. Further research is required to determine the long-term analgesic properties of this frequently used treatment modality in equine athletes.