Animals ; Chronic Pain ; Freund's Adjuvant/adverse effects* ; Humans ; Inflammation ; Male ; Pelvic Pain/etiology* ; Prostatitis ; Rats

Afferent Pathways ; drug effects ; Animals ; Freund's Adjuvant ; adverse effects ; Ganglia, Sensory ; drug effects ; Hyperalgesia ; chemically induced ; Inflammation ; Male ; Morphine ; pharmacology ; Rats ; Rats, Sprague-Dawley

AIMTo investigate the effects of extremely low magnetic field on acute and chronic arthritis of rats.

METHODSThe acute arthritis animal models were built by the right thenar hypodermic injection of carrageenan. Then they were exposed to magnetic field for 6 hours and 8 hours, respectively. The chronic arthritis animal models were built by the right thenar hypodermic injection of complete freund's adjuvant. They were exposed to magnetic field for 7 days and 6 hours each day after the secondary affection appeared 15 days later. The swelling and inflammatory cytokine were observed in both the acute and chronic arthritis models.

RESULTSThe ankle and thenar swellings decreased in both the acute and chronic arthritis models after different time exposure. The cytokine of serum and articular lixivium did not change in 6 hours exposed groups of acute arthritis models. The serum IL-6 and articular lixivium IL-6, TNF-alpha decreased compared with sham groups. Though the rest indexes were unchanged, they had the tendency of decrease.

CONCLUSIONThe extremely low magnetic field has the effects of restraining acute and chronic arthritis of rats, and can also partially restrain the cytokines when the rats were exposed for 8 hours. The mechanisms need to be further investigated.

Animals ; Arthritis, Experimental ; metabolism ; pathology ; Disease Models, Animal ; Edema ; prevention & control ; Freund's Adjuvant ; adverse effects ; Interleukin-6 ; metabolism ; Magnetic Fields ; Male ; Rats ; Rats, Sprague-Dawley ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo observe influence of electroacupuncture (EA) on phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2) in spinal cord dorsal horn (SCDH) in rats with acute inflammatory pain induced by complete Freund's adjuvant (CFA), further elucidate the immediate analgesic mechanism of EA via cellular signal transduction.

METHODSFifty-three healthy male SD rats were divided into two batches. The inflammatory pain models of the first batch of 23 rats were established by using CFA. The changes of the paw withdrawal thresholds (PWTs) of rats were observed and positive cells of p-ERK1/2 in affected SCDH were detected by using immunohistochemistry method. The second batch of 30 rats were randomly divided into a blank control group (N group), CFA group and EA group, 10 rats in each group. The rats of CFA group and EA group were induced inflammatory pain by using CFA, and the EA group was treated with EA at 5.5 h after the model establishment. The changes of PWTs and the positive cells of p-ERK1/2 in SCDH were observed.

RESULTSThe PWTs of the first batch of rats obviously decreased at 5 h, 3 d, 7 d and 14 d after CFA administration (all P< 0.01). However, the p-ERK1/2 positive cells in affected SCDH only increased at 5 h after CFA-injection and returned to normality at 3 d after the model establishment. In the second batch, compared with that of N group at the same time point, PWTs of rats in both CFA and EA group obviously decreased after the model establishment (both P<0.01). PWTs of rats in EA group which accepted EA treatment once were longer than those before EA treatment and corresponding PWTs in CFA group at the same time point (both P<0.01). Moreover, the numbers of p-ERK1/2 positive cells of affected SCDH increased significantly in CFA group at 6 h after the model establishment (P<0.01), however, which were decreased significantly in EA group (P<0.01).

CONCLUSIONInhibiting ERK1/2 activation of SCDH may be one of the pivotal mechanism of cellular signal transduction of the immediate analgesic effect educed by EA.

Acupuncture Analgesia ; Animals ; Back Pain ; chemically induced ; enzymology ; genetics ; therapy ; Electroacupuncture ; Freund's Adjuvant ; adverse effects ; Humans ; Male ; Mitogen-Activated Protein Kinase 1 ; genetics ; metabolism ; Mitogen-Activated Protein Kinase 3 ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Spine ; enzymology

OBJECTIVETo investigate the effect of the total flavonoids of orange peel (TFO) against adjuvant arthritis (AA) and the underlying mechanism.

METHODAA model was induced in male Wistar (correction of SD) rats by immunization with Freund's complete adjuvant Pad thickness was assayed by caliper. Pathological impairment of ankle joint was analysised by hematoxylin and eosin (H&E) staining. Levels of tumor necrosis factor (TNF)-alpha, Interleukin (IL)-1beta and prostaglandin (PG) E2 in serum was detected by radioimmunoassay method. Cyclooxygenase (COX)-2 expression in synovium tissues was measured by Western blot assay.

RESULTThe 75 mg x kg(-1) and 150 mg x kg(-1) TFO treatment obviously decreased the pad thickness and improve the pathological impairment of ankle joint of AA rats. In addition, abnormal elevation of TNF-alpha, IL-1beta and PGE2 in serum and COX-2 expression in synovium tissues of AA rats were markedly repressed by TFO treatment.

CONCLUSIONTFO can inhibit the development of AA in rats, and the mechanism were likely due to depressing inflammatory mediators production.

Animals ; Arthritis, Experimental ; chemically induced ; drug therapy ; immunology ; Citrus sinensis ; chemistry ; Disease Models, Animal ; Flavonoids ; administration & dosage ; Freund's Adjuvant ; adverse effects ; Humans ; Interleukin-1 ; immunology ; Male ; Plant Extracts ; administration & dosage ; Random Allocation ; Rats ; Rats, Wistar ; Tumor Necrosis Factor-alpha ; immunology

Collagen is the building component of temporomandibular joint (TMJ) discs and is often affected by inflammation in temporomandibular disorders. The macromechanical properties of collagen are deteriorated by chronic inflammation. However, the mechanism by which inflammation influences disc function remains unknown. The relationship between the ultrastructure and nanomechanical properties of collagen in inflamed discs should be clarified. Seven-week-old female Sprague-Dawley rats were randomly divided into two groups. Chronic TMJ inflammation was induced by intra-articular injection of complete Freund's adjuvant, and samples were harvested after 5 weeks. Picrosirius staining revealed multiple colours under polarized light, which represented alternative collagen bundles in inflamed discs. Using atomic force microscopy scanning, the magnitude of Young's modulus was reduced significantly accompanied with disordered collagen fibril arrangement with porous architecture of inflamed discs. Transmission electron microscopy scanning revealed a non-uniform distribution of collagen fibres, and oversized collagen fibrils were observed in inflamed discs. Fourier transform infrared microspectroscopy revealed a decrease in 1 338 cm/amide II area ratio of collagen in different regions. The peak positions of amide I and amide II bands were altered in inflamed discs, indicating collagen unfolding. Our results suggest that sustained inflammation deteriorates collagen structures, resulting in the deterioration of the ultrastructure and nanomechanical properties of rat TMJ discs.
Animals ; Collagen ; ultrastructure ; Female ; Fibrillar Collagens ; ultrastructure ; Freund's Adjuvant ; adverse effects ; Inflammation ; chemically induced ; metabolism ; pathology ; Injections, Intra-Articular ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Temporomandibular Joint ; Temporomandibular Joint Disc ; physiopathology ; ultrastructure ; Temporomandibular Joint Disorders ; physiopathology

OBJECTIVETo study the effect of geniposide-acid(GA) on the anti-inflammatory action for adjuvant-induced arthritis (AA) rats and the proliferation of synoviocytes in AA rats and the feasible mechanism of apoptosis in vitro.

METHODForty-eight health male Wistar rats were divided randomly into six groups and were administered respectively with 200, 100, 50 mg x kg(-1) GA and 0.75 mg x kg(-1) MTX and normal sodium (normal or model control group) for four weeks when right posterior paw pads of rats excluding normal control group were injected intrademally with complete Freund's adjuvant after 19 days. The left posterior paws swelling degree, swelling inhibition ratio and arthritis index of secondary inflamation were detected. The TNF-alpha and IL-1beta proteins in serum of rats were assayed by enzyme linked immunosorbent assay (ELISA) kits. The synovial fibroblasts of AA rats were exposed to 1-4 micromol x L(-1) GA or 4 micromol x L(-1) MTX. The effect of GA on the proliferation of synoviocytes was detected by MTT assay. The morphologic change of apoptosis cells was observed by Hoechst/PI double stainning and fluorescence microscope. The rate of apoptosis cells was analyzed by flow cytometry. The mRNA expresstion of Bcl-2 and Bax gene was detected by reverse transcription PCR (RT-PCR).

RESULT200 mg kg(-1) or 100 mg kg(-1) GA could decrease significantly the paw swelling degree, arthritis index and the level of TNF-alpha and IL-1beta proteins in serum of AA rats (P < 0.05 or P < 0.01) with 25.4%, 21.37% of the swelling inhibition ratio respectivly, 34.61%, 28% of protein inhibition ratio of TNF-alpha and 29.05%, 21.65% of that of IL-1beta. GA(1-4 micromol x L(-1)) inhibitated significantly the proliferation of synoviocytes culcured for 5 days. Flow cytometry showed that 1, 2, 4 micromol x L(-1) GA increased obviously the rate of apoptosis cells, the apoptosis ratios were 15.8%, 24.3%, 40.7% respectivly (P < 0.01). RT-PCR showed GA could decrease the expression level of Bcl-2 gene but increase that of Bax gene (P < 0.05 or P < 0.01).

CONCLUSIONGA could inhibit the secondary inflamation of AA rats and decrease the level of TNF-alpha and IL-1beta protein in the AA rats serum. GA could inhibit the proliferation of AA rat synoviocytes in vitro and induce apoptosis which mechanism was concerned with down-regulating the mRNA expression of Bcl-2 and up-regulating that of Bax.

Animals ; Anti-Inflammatory Agents ; administration & dosage ; Apoptosis ; drug effects ; Arthritis, Experimental ; chemically induced ; drug therapy ; immunology ; physiopathology ; Cytokines ; immunology ; Disease Models, Animal ; Freund's Adjuvant ; adverse effects ; Glucosides ; administration & dosage ; Humans ; Iridoid Glucosides ; Iridoids ; administration & dosage ; Male ; Random Allocation ; Rats ; Rats, Wistar ; Synovial Fluid ; cytology ; drug effects ; immunology

OBJECTIVETo study the antiinflammatory effects of naphtha from different chemotypes of Cinnamomum camphora and natural borneol on the rat arthritis model induced by Freund's adjuvant.

METHODThe arthritis model was induced by injecting Freund's adjuvant in rat voix pedis dermis and the rats were randomly divided into seven groups: normal control group, model control group, triptergium wilfordii control group, borneol chemotype naphtha group, camphor chemotype naphtha group, isocamphane chemotype naphtha group and natural borneol group. Rats of the triptergium wilfordii control group were given orally 8.1 mg x kg(-1) triptergium wilfordii for 35 days, rats of the normal control group and model control group were given same volume water, and rats of other groups were given 80 mg x kg(-1) corresponding drug. We observed the rat common condition, weighed the rat body weight weekly, measured the degree of swelling of voix pedis every 4 days, weighed the thymus and spleen on the end of life, and measured the contents of cell factor TNF-alpha, IL-2, and IL-6 in rat blood serum.

RESULTAs far as the arthrosis degree of swelling and the contents of cell factor TNF-alpha, IL-2, IL-6 were concerned, rats of model control group were higher than normal control group, and rats of other drug groups were lower than the model control group. The order of inhibition ratios of the arthrosis degree of swelling from high to low principle was isocamphane chemotype naphtha group, camphor chemotype naphtha group, borneol chemotype naphtha group and natural borneol group. All medication administration teams evidently reduced the contents of the IL-2 and IL-6, and the inhibition ratios were higher than 38%. In the case of the contents of TNF-alpha and IL-2, all groups were not evidently different. In the case of inhibition of IL-6, camphor chemotype naphtha group was better than borneol chemotype naphtha group and natural borneol group, the latter was better than isocamphane chemotype naphtha group. As far as the weight, thymus index and spleen index were concerned, all medication administration groups were not different.

CONCLUSIONThe different chemotypes of C. camphora have anti-inflammatory effect on the rat arthritis model induced by Freund's adjuvant, but pharmacological activity and mechanism of action are different. The study points out the clinical curative effects of the chemotypes of the kindred medicinal plant are different, and please consider the difference of chemotype in clinical application.

Alkanes ; therapeutic use ; Animals ; Anti-Inflammatory Agents ; therapeutic use ; Arthritis ; chemically induced ; drug therapy ; metabolism ; Body Weight ; drug effects ; Bornanes ; therapeutic use ; Cinnamomum camphora ; chemistry ; Freund's Adjuvant ; adverse effects ; Interleukin-2 ; metabolism ; Interleukin-6 ; metabolism ; Male ; Random Allocation ; Rats ; Rats, Wistar ; Tumor Necrosis Factor-alpha ; metabolism

Recent studies have shown that the chemokine receptor CXCR3 and its ligand CXCL10 in the dorsal root ganglion mediate itch in experimental allergic contact dermatitis (ACD). CXCR3 in the spinal cord also contributes to the maintenance of neuropathic pain. However, whether spinal CXCR3 is involved in acute or chronic itch remains unclear. Here, we report that Cxcr3 mice showed normal scratching in acute itch models but reduced scratching in chronic itch models of dry skin and ACD. In contrast, both formalin-induced acute pain and complete Freund's adjuvant-induced chronic inflammatory pain were reduced in Cxcr3 mice. In addition, the expression of CXCR3 and CXCL10 was increased in the spinal cord in the dry skin model induced by acetone and diethyl ether followed by water (AEW). Intrathecal injection of a CXCR3 antagonist alleviated AEW-induced itch. Furthermore, touch-elicited itch (alloknesis) after compound 48/80 or AEW treatment was suppressed in Cxcr3 mice. Finally, AEW-induced astrocyte activation was inhibited in Cxcr3 mice. Taken together, these data suggest that spinal CXCR3 mediates chronic itch and alloknesis, and targeting CXCR3 may provide effective treatment for chronic pruritus.
Acetamides ; therapeutic use ; Animals ; Chemokine CXCL10 ; metabolism ; Chloroquine ; toxicity ; Chronic Disease ; Cyclopropanes ; adverse effects ; Dehydration ; complications ; Dinitrofluorobenzene ; adverse effects ; Disease Models, Animal ; Formaldehyde ; toxicity ; Freund's Adjuvant ; toxicity ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Motor Activity ; drug effects ; Pain ; chemically induced ; Pruritus ; chemically induced ; pathology ; Pyrimidines ; therapeutic use ; Receptors, CXCR3 ; antagonists & inhibitors ; genetics ; metabolism ; Skin ; pathology ; Spinal Cord ; drug effects ; metabolism ; pathology ; Time Factors ; p-Methoxy-N-methylphenethylamine ; toxicity

5-hydroxytryptamine (5-HT) released in inflammatory tissues plays a pivotal role in pain hypersensitivity. However, it is not clear whether 5-HT2A receptors in the inflamed tissues mediate this effect. The present study investigated the contribution of 5-HT2A receptors in the periphery to chronic inflammatory pain. Complete Freund's adjuvant (CFA) was injected subcutaneously in the hindpaw of rats. The selective 5-HT2A receptor antagonist ketanserin was given in the inflamed site. Paw withdrawal latency responding to heat or mechanical stimuli was measured. Expression of neuropeptide Y (NPY) in the spinal dorsal horn and dorsal root ganglia (DRG) was assayed using immunohistochemistry technique. The results showed that ketanserin administered in the inflamed site inhibited thermal hyperalgesia in a dose-dependent manner (20, 40 and 80 µg) induced by the intraplantar injection of CFA. Ketanserin given once per day at a dose of 80 µg abolished heat hyperalgesia and also attenuated mechanical allodynia on the third day. CFA injection increased the expression of NPY in superficial laminae of the spinal cord, but not in the DRG. The local treatment of ketanserin completely inhibited CFA-induced increase in NPY expression in superficial laminae of the spinal cord. These results indicated that activation of 5-HT2A receptors in the inflamed tissues was involved in the pathogenesis of inflammatory pain and the blockade of 5-HT2A receptors in the periphery could relieve pain hypersensitivity and normalize the cellular disorder in the spinal dorsal horn associated with pathological pain. The present study suggests that the peripheral 5-HT2A receptors can be a promising target for pharmaceutical therapy to treat chronic inflammatory pain without central nervous system side effects.
Animals ; Freund's Adjuvant ; adverse effects ; Ganglia, Spinal ; metabolism ; Hot Temperature ; Hyperalgesia ; chemically induced ; drug therapy ; Inflammation ; drug therapy ; Ketanserin ; pharmacology ; Neuropeptide Y ; metabolism ; Pain ; drug therapy ; Pain Measurement ; Rats ; Receptor, Serotonin, 5-HT2A ; metabolism ; Serotonin ; Serotonin 5-HT2 Receptor Antagonists ; pharmacology ; Spinal Cord Dorsal Horn ; metabolism