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At least 1,711 records · Page 95Linked to original sources

PubMed2002

Evidence that peroxisome proliferator-activated receptor alpha is complexed with the 90-kDa heat shock protein and the hepatitis virus B X-associated protein 2.

The peroxisome proliferator-activated receptor alpha (PPARalpha) is a ligand-inducible transcription factor, which belongs to the nuclear receptor superfamily. PPARalpha mediates the carcinogenic effects of peroxisome proliferators in rodents. In humans, PPARalpha plays a fundamental role in regulating energy homeostasis via control of lipid metabolism. To study the possible role of chaperone proteins in the regulation of PPARalpha activity, a monoclonal antibody (mAb) was made against PPARalpha and designated as 3B6/PPAR. The specificity of mAb 3B6/PPAR in recognizing PPARalpha was tested in immunoprecipitations using in vitro translated PPAR subtypes. The mAb 3B6/PPAR recognized PPARalpha, failed to bind to PPARbeta or PPARgamma, and is efficient in both immunoprecipitating and visualizing the receptor on protein blots. The immunoprecipitation of PPARalpha in mouse liver cytosol using mAb 3B6/PPAR has resulted in the detection of two co-immunoprecipitated proteins, which are heat shock protein 90 (hsp90) and the hepatitis B virus X-associated protein 2 (XAP2). The concomitant depletion of PPARalpha in hsp90-depleted mouse liver cytosol was also detected. Complex formation between XAP2 and PPARalpha/FLAG was also demonstrated in an in vitro translation binding assay. hsp90 interacts with PPARalpha in a mammalian two-hybrid assay and binds to the E/F domain. Transient expression of XAP2 co-expressed with PPARalpha resulted in down-regulation of a peroxisome proliferator response element-driven reporter gene activity. Taken together, these results indicate that PPARalpha is in a complex with hsp90 and XAP2, and XAP2 appears to function as a repressor. This is the first demonstration that PPARalpha is stably associated with other proteins in tissue extracts and the first nuclear receptor shown to functionally interact with XAP2.

Animals↗

PubMed2000

Leptin expression is reduced with acute endotoxemia in the pig: correlation with glucose, insulin, and insulin-like growth factor-1 (IGF-1).

Leptin has been implicated in the regulation of anorexia associated with cachexia in rodents and humans. Regulation of leptin expression is under complex endocrine and metabolic control. To determine if leptin expression is regulated by acute inflammation and to define the endocrine and metabolic factor(s) that regulates leptin expression during acute inflammation, castrate male pigs (ad libitum fed, used as their own controls) were treated with saline (control period) and endotoxin (lipopolysaccharide [LPS] period). Frequent blood samples were collected to identify dynamic changes in hormones and metabolites that are known to regulate leptin expression. LPS caused fever and elevated plasma cortisol (p < 0.0004), tumor necrosis factor-alpha (TNF-alpha) (p < 0.0001), and plasma nonesterified fatty acids (NEFA) (p < 0.001) compared with control. Circulating insulin (p < 0.01), glucose (p < 0.003), and insulin-like growth factor-1 (IGF-1) (p < 0.0001), as well as adipose leptin mRNA abundance (p < 0.01), were profoundly reduced following LPS treatment compared with control. Our data indicate that during acute endotoxemia (1-10 h after injection), leptin gene expression is decreased compared with ad libitum fed animals and is more closely related to energy homeostasis than cytokine profiles in plasma.

Animals↗

PubMed1991

Dietary plant materials and development of diabetes in the BB rat.

The present study was designed to examine further the impact of individual plant protein sources found in a diabetogenic, cereal-based, rodent laboratory diet, NIH-07 [open formula, nonpurified rat and mouse diet (positive control)], on the development of diabetes. Diabetes-prone BB rats that were pan-T(OX19+)-lymphopenic were fed a low diabetogenic diet during gestation and lactation. Progeny of these rats were fed a normal or autoclaved NIH-07 diet, or one of eight other diets based on the AIN-76A formulation, with modified protein sources as follows: hydrolyzed casein (HC), soybean meal, HC+ trypsin inhibitor (TI) in water (2 mg/mL, wheat germ, alfalfa seeds, Brewer's yeast, red lentils and a plant protein mixture. Feeding soybean meal increased the incidence of diabetes compared with the negative control, HC diet (47% vs. 12% incidence, P = 0.02). Wheat germ, alfalfa seeds and plant protein mixture resulted in an intermediate incidence of diabetes of 33%; the incidence was lower for Brewer's yeast and lentils (20% and 13%). Autoclaving (121 degrees C, 10 min) the NIH-07 diet or the presence of TI in drinking water had a minimal effect on diabetes frequency, suggesting heat-labile plant toxicants were not directly involved. Thus, certain dietary plant protein sources or associated agents may influence the development of spontaneous diabetes in the BB rat.

Age Factors↗

PubMed1989

The periodontal enigma: eruption versus tooth support.

The response of the periodontal ligament is reviewed when single or repeated loads are applied to the tooth, as in mastication. A more nearly elastic recovery is produced with simulated chewing than is indicated by single semi-static applications of force. The resting position of the tooth between loadings changes with the time of day and recent loading history. An unstressed tooth extrudes at a variable rate. Soon after entry into the mouth, extrusion is a progressive feature, which manifests as eruption with consequent structural rearrangement of the periodontium. Rates of extrustion are substantially higher than eruption. Experimental evidence is presented that newly erupted teeth of monkey erupt in a similar manner to rodent incisors. Thus reduction in masticatory loads allows teeth to erupt faster than control teeth. It is concluded that the ligament is well constructed to withstand the large but short-acting forces which occur in mastication and which cause relatively small, long term effects, on the position of the tooth in the alveolus. When unstressed, mechanisms in the ligament of a tooth with a developing or fully formed root, generate a continuous net force in the order of a gram tending to cause extrusion. The position a tooth adopts is determined by the interplay of these opposing sets of greatly differing forces.

Animals↗

PubMed1986

Photoperiod, follicle-stimulating hormone receptors, and testicular function in vizcacha (Lagostomus maximus maximus).

In the present work we investigated the presence of testosterone in serum and follicle-stimulating hormone (FSH) receptors in testes of the vizcacha (Lagostomus maximus maximus), a South American rodent. We also investigated the effect of constant light on both parameters. The control group consisted of vizcachas caught in their natural habitat and maintained under continuous darkness; the experimental group consisted of animals maintained under constant light (1076 lx) for 8 days. The results revealed a significant decrease in serum testosterone and FSH receptors when the animals were maintained under constant light, as compared to the control group. Androstenedione was elevated in the serum obtained from the experimental group. It is postulated that the pineal gland may regulate testosterone secretion through FSH receptors and through an enzymatic blockade in the steroidogenic pathway; this supposition, however, remains to be proved.

Androstenedione↗

PubMed2003

Effects of recombinant human tissue inhibitor of metalloproteinases-2 (rh-TIMP-2) on migration of epidermal keratinocytes in vitro and wound healing in vivo.

Tissue inhibitors of metalloproteinases (TIMP), common inhibitors of matrix proteinases, have cell-promoting activity. We studied the effects of recombinant human tissue inhibitor of metalloproteinases-2 (rh-TIMP-2) on the migration of normal human epidermal keratinocytes (NHEK). An in vitro migration assay revealed that rh-TIMP-2 enhanced random migration (up to 170%, p<0.05) in a dose-dependent manner. When we applied rh-TIMP-2 solution (20 microg/20 microl/wound) daily to full-thickness wounds made with an 8-mm punch on the backs of healthy (n=8), aged (n=9), and diabetic (n=15) rodents, we observed faster wound closure (p<0.05) than in vehicle-treated controls. Accelerated wound closure was dose-dependent (0-20 microg/wound) in diabetic mice (n=6), and the optimal concentration was 10-20 microg of rh-TIMP-2/wound. Histological examinations performed on days 0, 5, 10, 15, and 20 in diabetic mice revealed faster migration of epidermal keratinocytes from wound edges. These results suggest that rh-TIMP-2 plays an important role in wound healing.

Animals↗

PubMedDate not supplied

Effect of nutritional stress on the hypothalamo-pituitary-gonadal axis in the growing male rat.

BACKGROUND/OBJECTIVE: Nutritional dwarfing (ND) consists of a decrease in weight and height gain and delayed onset of puberty. The aim of the present investigation was to study the modifications induced in male rats by the nutritional stress of a mere 20% reduction in food intake which, however, started immediately after weaning. MATERIALS AND METHODS: At weaning, male Wistar rats were divided into two groups: Control (C) and ND. C rats were fed ad libitum with a balanced rodent diet. ND received 80% of the diet consumed by C for 4 weeks (T4); then they were fed ad libitum for another 4 (T8) and 8 weeks (T12). The rats were studied at T0, T4, T8 and T12 for the effects of nutritional stress and refeeding on nutritional status, body composition, hypothalamic-pituitary-gonadal axis, and sperm morphology and concentration. RESULTS: ND body weight and length diminished vs. C (p < 0.001). ND body fat percentage decreased 40% (p < 0.001) without change in the percentage of body protein content. The hypothalamic content of LHRH did not change. However, FSH, LH and testosterone serum levels had significantly decreased (p < 0.001) at T4 in ND rats. A 48.4 % decrease in serum leptin in the ND group was observed at T4 (p < 0.05). The absolute testicular and seminal vesicle weight was significantly decreased by ND at T4 (p < 0.001). At T4 the percentage of anomalies of caudal spermatozoa increased in about 64% (p < 0.001) of ND vs. C rats, despite the unchanged sperm concentrations. All parameters normalized during refeeding. CONCLUSION: In this model, a decrease in leptin due to nutritional stress could be responsible, at least in part, for the inhibition of reproductive function. Refeeding normalized all parameters studied.

Animals↗

PubMed1997

Low-density lipoprotein receptor knockout mice exhibit exaggerated microvascular responses to inflammatory stimuli.

The objective of this study was to determine whether genetically induced hypercholesterolemia affects leukocyte-endothelial cell interactions in postcapillary venules of the mouse cremaster muscle. Leukocyte adhesion, emigration, and other microvascular parameters were assessed in venules of normal (wild-type) and low-density lipoprotein receptor-deficient (LDLr-/-) mice maintained on either normal rodent chow or on a high cholesterol diet (HCD). Measurements were obtained under control conditions and after administration of either leukotriene B4 (LTB4), platelet-activating factor (PAF), or tumor necrosis factor-alpha (TNF-alpha). Elevated numbers of adherent and emigrated leukocytes were observed in venules of LDLr-/- (compared with wild-type) mice on HCD, both under baseline conditions and after exposure to either LTB4, PAF, or TNF-alpha. Plasma TNF-alpha levels were also elevated in LDLr-/- versus wild-type mice. Administration of blocking monoclonal antibodies demonstrated that intercellular adhesion molecule-1, but not vascular cell adhesion molecule-1, mediates the exaggerated leukocyte-endothelial cell adhesion observed in LDLr-/- mice. The results of these studies indicate that chronic hypercholesterolemia predisposes the microvasculature to intense leukocyte-endothelial cell adhesion in response to different inflammatory stimuli.

Animals↗

PubMed2003

Selective inhibitors of the osteoblast proteasome stimulate bone formation in vivo and in vitro.

We have found that the ubiquitin-proteasome pathway exerts exquisite control of osteoblast differentiation and bone formation in vitro and in vivo in rodents. Structurally different inhibitors that bind to specific catalytic beta subunits of the 20S proteasome stimulated bone formation in bone organ cultures in concentrations as low as 10 nM. When administered systemically to mice, the proteasome inhibitors epoxomicin and proteasome inhibitor-1 increased bone volume and bone formation rates over 70% after only 5 days of treatment. Since the ubiquitin-proteasome pathway has been shown to modulate expression of the Drosophila homologue of the bone morphogenetic protein-2 and -4 (BMP-2 and BMP-4) genes, we examined the effects of noggin, an endogenous inhibitor of BMP-2 and BMP-4 on bone formation stimulated by these compounds and found that it was abrogated. These compounds increased BMP-2 but not BMP-4 or BMP-6 mRNA expression in osteoblastic cells, suggesting that BMP-2 was responsible for the observed bone formation that was inhibited by noggin. We show proteasome inhibitors regulate BMP-2 gene expression at least in part through inhibiting the proteolytic processing of Gli3 protein. Our results suggest that the ubiquitin-proteasome machinery regulates osteoblast differentiation and bone formation and that inhibition of specific components of this system may be useful therapeutically in common diseases of bone loss.

Animals↗

PubMed1986

In vitro models for studying the molecular biology of carcinogenesis.

Although carcinogens cause various similar deleterious effects on rodent and human cells, only rodent cells can convert to malignancy in a quantitative, predictable fashion. Therefore, the control mechanisms involving indefinite proliferation and tumorigenicity are different. Human cell lines may exhibit normal or aneuploid chromosome constitutions with numerical or structural alterations frequently involving proto-oncogene loci, but fail to produce progressively growing tumors in nude mice. A new approach for obtaining human cells susceptible to malignant transformation by chemical or physical carcinogens is to use DNA from a cancer associated virus. Transfection of human papilloma virus (HPV) DNA associated with genital cancer can extend life-span of human cells; post-X-irradiated cells grow in agar suspension. Southern blot analysis of extracted DNA indicates that HPV sequences persist. Similar results are obtained with human fibroblast and epithelial cells.

Animals↗

PubMed2004

Resuscitation affects microcirculatory polymorphonuclear leukocyte behavior after hemorrhagic shock: role of hypertonic saline and pentoxifylline.

We have previously shown that lung injury following fluid resuscitation either with hypertonic saline (HS) or lactated Ringer's (LR) plus pentoxifylline (PTX) attenuated acute lung injury when compared with LR resuscitation. The objective of the present study is to determine whether our previous observations are accompanied by changes in polymorphonu-clear leukocyte (PMN) behavior. To study this, PMN-endothelial cell interactions, microcirculatory blood flow, lung histology, lung PMN infiltration (MPO, Myeloperoxidase), and lung intra-cellular adhesion molecule-1 (ICAM-1) expression were assessed in a controlled hemorrhagic shock model followed by LR, HS, and LR+PTX resuscitation in rodents. Rats (240-300 g) were bled to a mean arterial pressure (MAP) of 35 mm Hg for 1 hr and then randomized into three groups: HS (7.5% NaCl, 4 ml/kg); LR (3x shed blood); and LR+PTX (25 mg/kg). Additionally, total shed blood was reinfused. A sham group underwent no shock and no treatment. The internal spermatic fascia was exteriorized and the microcirculation was observed by closed-circuit TV coupled to a microscope, 2 and 6 hrs after treatment. The number of leukocytes sticking to the venular endothelium was determined 2 hrs after fluid resuscitation. Microcirculatory blood flow was measured by an optical Doppler velocimeter. Lung histology and lung MPO immunostaining were assessed at 6 hrs, and lung ICAM-1 expression was determined by immunostaining at 2 hrs following fluid resuscitation. Two hours after treatment, HS (1.4 +/- 0.4), LR+PTX (1.7 +/- 0.3), and sham (0.4 +/- 0.2) groups presented significant reductions in leukocyte adherence (cells/100 microm venule length), compared with the LR group (4.0 +/- 0.9, P < 0.05). No differences were observed 6 hrs after treatment on leukocyte adherence and microcirculatory blood flow. ICAM-1 expression was significantly higher in LR-treated animals compared with the HS, LR+PTX, and sham groups (P < 0.01). PMN infiltration and overall lung injury were significantly attenuated by HS and LR+PTX. These results support earlier studies that indicated the potential application of HS and PTX in shock therapy and the increase in PMN-endothelial cell interaction and lung injury after LR resuscitation.

Animals↗

PubMed2004

Artificial rearing of mouse pups: development of a mouse pup in a cup model.

Artificial rearing of rat pups has been used in the investigation of the neonatal gut. We propose to adapt the model of artificially rearing rat pups for use in mouse pups, thereby allowing the use of transgenic animals for our research. We hypothesized that gastrostomy catheters may be placed successfully into neonatal mouse pups and that the pups may be artificially reared without significant alterations in their growth or intestinal development. Gastrostomy tubes are placed into 5-d-old mouse pups [artificially reared (AR); n = 32], and the mice are fed rodent milk substitute. Littermate pups [maternally reared (MR); n = 22] are used as controls. After 5 d, pups are killed and their organs are harvested. Intestinal villus measurements, protein content, and DNA content are determined. Data are reported as mean +/- SEM, compared with appropriate statistical methods, and significance is determined at P < 0.05. Initial weights and lengths are not different between the two groups, but after 5 d, MR pups weigh more than their AR counterparts (5.0 +/- 0.13 versus 4.1 +/- 0.14 g, MR versus AR; P < 0.01). However, the pups' length and the intestinal villus height-to-width ratios, protein, and DNA content are not different between the MR and AR pups. To our knowledge, this is the first report of artificially rearing mouse pups. Development of this technique will permit nutritional manipulation in neonatal mice, a mammalian model wherein the genome is sequenced and transgenic mutants are available.

Animals↗

PubMed2003

Interleukin-6 levels in the central nervous system are negatively correlated with fat mass in overweight/obese subjects.

Recently, we demonstrated that intracerebroventricular injection of IL-6 increases energy expenditure and decreases body fat in rodents. Therefore, IL-6 may play a role in appetite and body weight control in the central nervous system. In the present study we evaluated cerebrospinal fluid (CSF) and serum IL-6 levels in humans in relation to body fat content and to CSF and serum levels of leptin. Thirty-two healthy overweight/obese male subjects with a body mass index range of 29.3-36.0 kg/m(2) were studied. Total and sc body fat were measured by dual energy x-ray absorptiometry and computed tomography, respectively. CSF IL-6 levels were in some individuals higher than serum IL-6 levels and correlated negatively with total body weight, sc and total body fat. In contrast, CSF leptin levels were 30-60 times lower than serum leptin levels and correlated positively with serum leptin, body weight, sc and total body fat. Furthermore, there was a negative correlation between CSF IL-6 and leptin. In conclusion, CSF IL-6 differs in many ways from CSF leptin. CSF IL-6 may be locally produced rather than serum derived, and body fat-regulating regions in the central nervous system may be exposed to insufficient IL-6 levels in more severe obesity.

Absorptiometry, Photon↗

PubMed1991

[Effects of FOY-305 on post-operative reflux esophagitis in rats (I). Effects of FOY-305 on reflux esophagitis after total gastrectomy in rats].

We investigated the effect of camostat mesilate (FOY-305), an oral protease inhibitor, on reflux esophagitis after total gastrectomy followed by an end-to-side esophago-jejunostomy (Billroth-II) in rats. Effects of FOY-305 were compared with those of sodium alginate (AL-Na) and cimetidine. On the basis that esophageal ulceration occurred from post-operative day 5 in this model, rodents were fed with special chows containing test drugs from day 2 for 5 or 12 days in order to examine the prophylactic effects (Exp. I) and from day 7 for two weeks in healing experiments (Exp. II). In Exp. I, FOY-305 significantly prevented esophageal ulceration on post-operative days 7 and 14. However, AL-Na significantly prevented esophageal ulceration on post-operative day 7 but not on day 14. In Exp. II, FOY-305 had a remarkable therapeutic effect on esophageal ulceration on day 21. Food intake and body weight of rodents in the FOY-305-treated group were higher than those in the control group. In pathohistological studies, FOY-305 elicited an inhibitory effect on ulceration and induced esophageal mucosal regeneration at the ulceration sites. In contrast, AL-Na and cimetidine did not have any significant therapeutic effect. These results suggest that FOY-305 is an effective agent for the treatment of reflux esophagitis after total gastrectomy.

Alginates↗

PubMed2002

Marked extension of proliferation of rat Sertoli cells in culture using recombinant human FSH.

Previous studies indicate that proliferation of rat Sertoli cells in culture can only be maintained until the equivalent of days 10-12 after birth, irrespective of the age of the donor animal. This report describes methods for the isolation and culture of Sertoli cells from day 6 rat testes, which can proliferate in culture for 20-24 days (that is, until the equivalent of days 26-30 after birth). Cells were isolated by enzymatic digestion of seminiferous cords followed by selective depletion of contaminating peritubular cells by adhesion to a polystyrene surface. The purity of the Sertoli cells was assessed using a combination of markers to be > 99.5%. Proliferation was assayed using tritiated thymidine incorporation and further verified by bromodeoxyuridine histochemistry and flow cytometry. Sertoli cells proliferated at basal levels in Dulbecco's modified Eagle's medium (DMEM)-F12 media alone, and proliferation was stimulated further by addition of recombinant human FSH to the culture media. After 20-24 days in culture, proliferation rapidly ceased, and cells assumed abnormal morphology and detached from the culture vessel; these events are consistent with the cells undergoing classic rodent cell senescence. The method described provides a useful tool for investigating the control of Sertoli cell division. Furthermore, these findings indicate that the timely differentiation of Sertoli cells is not dependent solely on an intrinsic timing mechanism, as has been suggested previously.

Animals↗

PubMed2004

The cultured rodent follicle as a model for investigations of gonadotrophin surge-attenuating factor (GnSAF) production.

Gonadotrophin surge-attenuating factor (GnSAF) bioactivity (the suppression of GnRH-induced but not basal LH and FSH secretion from pituitary gonadotrophs) is produced by granulosa cells in vitro. Previous studies to investigate this bioactivity used dispersed granulosa cells which lack some cell types and the structural components of the follicle in vivo. The aim of this study, therefore, was to investigate whether intact rodent follicle culture was a suitable model for the study of the production of GnSAF bioactivity, allowing GnSAF to be investigated in a more physiologically realistic environment while still retaining culture conditions from which, as with granulosa cell cultures, extraneous factors can be excluded. Follicles from 16-day-old rats and 21-day-old mice were cultured for 3-6 days in the presence or absence of FSH and/or LH. The follicle-conditioned medium, and matching samples of unconditioned culture medium were added to our established rat pituitary monolayer GnSAF bioassay. Both mouse and rat intact follicles produced GnSAF bioactivity, reducing GnRH-induced LH secretion significantly. GnSAF output from the mouse follicles was highest during days 1-3 of culture, when follicles were at an early antral stage of development, and fell on days 4-6 as the follicles grew to the mid antral stage. While the stimulatory effects of FSH on rat follicle GnSAF secretion was dose-dependent, LH alone did not increase GnSAF production. An antibody against human GnSAF blocked GnSAF bioactivity produced by rat follicles, and recognised proteins within the expected pI and molecular weight range for GnSAF in two-dimensional gels of rat follicle-conditioned medium, showing a good homology between rodent and human GnSAF proteins. In conclusion, the release of GnSAF bioactivity is principally from small follicles stimulated by FSH. Therefore, intact rodent follicle culture systems offer an excellent model for the investigation of factors controlling GnSAF production under relatively physiological conditions.

Animals↗

PubMed2004

Lassa fever vaccine.

Lassa fever remains a serious challenge to public health in West Africa threatening both local residents in rural areas and those who serve them, particularly medical care providers. Given the ecology of the rodent host and conditions in the endemic area, a vaccine is mandatory for control. The challenge is to overcome the scientific, political and economic obstacles to producing a human use vaccine candidate. There are some scientific issues to resolve. It is known that the G-protein confers protection but we do not know its duration. If the N-protein is also included there may be a better duration of protection but it is unclear whether the N-protein as a vaccine may possibly enhance the infection. The original vaccinia vector must be replaced by new vectors, chimeras or by delivering DNA in some format. A live vaccine is attractive because it can confer protection in a single shot. A killed vaccine is more stable, particularly for distribution in the tropics but usually requires repeated shots. For practical reasons a live vaccine format should probably be pursued, which could then be combined with a yellow fever vaccine, using the same cold chains, since this disease occupies the same endemic areas in West Africa. Lassa vaccine initiatives have suffered from a lack of funding in the past but bioterrorism has brought new resources to Lassa virus science. Adequate funding and applications of new vaccine technologies give hope that we may soon see a vaccine in clinical trials. However, the difficulty of conducting trials in endemic areas and lack of political stability remain serious problems.

Africa, Western↗

PubMed2006

Matrix metalloproteinase-9 activity in the cerebrospinal fluid and serum of dogs with acute spinal cord trauma from intervertebral disk disease.

OBJECTIVE: To detect matrix metalloproteinase (MMP)-9 in serum and CSF and determine relationships between MMP activity and severity of disease, duration of clinical signs, and duration of hospitalization in dogs with acute intervertebral disk disease (IVDD). ANIMALS: 35 dogs with acute IVDD and 8 clinically normal control dogs. PROCEDURE: CSF and serum were collected from affected and control dogs. Zymography was used to detect MMP-9. RESULTS: Activity of MMP-9 in CSF was detected in 6 of 35 dogs with IVDD; activity was significantly more common in dogs with duration of signs < 24 hours. Paraplegic dogs were more likely to have MMP-9 activity in the CSF than non-paraplegic dogs. No significant difference in hospitalization time was detected in dogs with IVDD between those with and without activity of MMP-9 in the CSF. Serum MMP-9 was detected more frequently in dogs with IVDD than in control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Data were consistent with results of experimental rodent spinal cord injury studies that indicate that MMP-9 is expressed early during secondary injury.

Animals↗