Modulating Effects of the Hydroethanolic Leaf Extract of Persicaria lanigera R. Br. Soják (Polygonaceae) against Acute Inflammation.

Plant species have been used traditionally to treat numerous inflammatory disorders because of their known medicinal properties. This study aimed to assess the anti-inflammatory effect of aqueous ethanolic leaf extract of Persicaria lanigera using acute inflammatory models. The safety profile of the Persicaria lanigera extract was assessed using an acute toxicity model. The anti-inflammatory effect of the Persicaria lanigera leaf extract (100-600 mg·kg-1, p.o.) was studied in carrageenan-induced paw oedema, zymosan-induced knee joint arthritis, and histamine-induced paw oedema in Sprague-Dawley rats (n = 5). It was observed that the Persicaria lanigera leaf extract administered prophylactically significantly inhibited paw oedema from 99.01 ± 12.59 to 59.10 ± 4.94%, 56.08 ± 3.65%, and 48.62 ± 3.27% at 100 mg·kg-1, 300 mg·kg-1, and 600 mg·kg-1, while the standard drug, aspirin, showed 41.84 ± 9.25% in carrageenan-induced paw oedema, respectively. Furthermore, the extract decreased knee joint inflammation significantly from 62.43 ± 5.73% to 32.07 ± 2.98% and 24.33 ± 8.58% at 300 mg·kg-1 and 600 mg·kg-1 in zymosan-induced knee joint inflammation, respectively. In the histamine-induced paw oedema model, the extract significantly inhibited oedema to 61.53 ± 9.17%, 54.21 ± 9.38%, and 54.22 ± 9.37% at the same doses. Aqueous ethanolic leaf extract of Persicaria lanigera is safe and attenuates inflammation in acute inflammation models.

No adverse effects on periarticular tissue by intra-articular vitamin D analogue calcipotriol in a reduced-dose zymosan-induced arthritis model in rats.

Calcipotriol, a vitamin D analogue, is an antiproliferative and anti-inflammatory drug currently used in psoriasis. Here, our aim was to analyse the safety of calcipotriol for cartilage and bone in alleviated-dose (0.1 mg instead of usual ≥1mg dose) zymosan-induced arthritis in rats. Theoretically, high doses of vitamin D or analogues could have detrimental effects on bone or cartilage. The rats were divided into four groups: vehicle (n = 9), dexamethasone 0.1 mg/kg (n = 9), calcipotriol 0.1 mg/kg (n = 8) and negative control (n = 10) with no injections. Arthritic rats were given phosphate-buffered saline (PBS) injections to left knees as a control. After euthanasia on day 8, all knees were imaged with micro-computed tomography for surface lesions and decalcified for histological analyses. Contrary to our expectations, no significant changes could be observed in the tomography data and histological scores among the three treatment groups or between the vehicle-treated and non-arthritic group. Calcipotriol did not cause adverse effects on cartilage or subchondral bone within a week, suggesting that it could be safely used in local treatment of arthritis. The alleviated model caused synovitis with local and systemic inflammatory response without cartilage erosions, which might be useful in studying self-limiting synovitis where cartilage or bone effects are not of primary interest.

Beneficial effect of Bletilla striata extract solution on zymosan-induced interstitial cystitis in rat.

AIMS: Interstitial cystitis (IC) is a chronic pain syndrome that is characterized by suprapubic pain upon bladder filling. Bletilla striata, a well-known traditional Chinese herb with established efficacy in wound healing and anti-inflammation, was hypothesized to improve the symptoms of IC possibly though forming a physical barrier that could isolate the bladder tissue from irritants. This study was conducted to evaluate the beneficial effects of intravesical treatment with B. striata extract solution (BSES) on visceral pain and bladder function of rats with zymosan-induced IC. METHODS: Thirty female rats were randomly divided into control group, zymosan-induced cystitis rats treated with normal saline (Z + NS), and zymosan-induced cystitis rats treated with BSES (Z + BSES). All rats underwent evaluation for abdominal withdrawal reflex (AWR) scores to assess visceral hypersensitivity, cystometrography, and electromyogram (EMG) of both external urethral sphincter and bladder detrusor. Data were analyzed by one way analysis of variance. RESULTS: The Z + NS group had an increased visceral hypersensitivity as compared to control group. Rats treated with BSES (Z + BSES group) had decreased AWR scores and amplitude of bladder detrusor-EMG. Besides, BSES treatment improved overactive bladder with significant effects on the extend of micturition interval and increase of storage of urine. CONCLUSIONS: Intravesical instillation of BSES can significantly alleviate zymosan-induced visceral hypersensitivity and bladder overactivity associated with IC. This study suggested that intravesical instillation with BSES might be a promising treatment for IC.

Sulfated polysaccharide from Gracilaria caudata reduces hypernociception and inflammatory response during arthritis in rodents.

Polysaccharide from marine alga Gracilaria caudata has potential health benefits, such as anti-inflammatory, gastroprotective and antidiarrheal effects. Here, we investigated the effect of a sulfated polysaccharide from G. caudata (SP-GC) on hypernociception and inflammatory response in arthritis models. The animals received SP-GC (3, 10 or 30 mg/kg) 1 h before tibio-tarsal injection of zymosan. Hypernociception, histopathology, edema, vascular permeability, myeloperoxidase (MPO) activity, cell influx, interleukin (IL)-1ß and nitric oxide (NO) levels were evaluated in acute phase. In another protocol, animals received SP-GC (30 mg/kg) 2 h post-complete Freund's adjuvant (CFA). Hypernociception, edema and arthritis index were determined in acute, sub-chronic and chronic phases. Rota-rod test measured the motor performance. SP-GC significantly reduced, in a dose-dependent manner, the zymosan-induced hypernociception with maximal effect at 30 mg/kg. The microscopic inflammation, joint edema, MPO activity, cell influx, IL-1ß and NO levels were also reduced by SP-GC. In the CFA-induced arthritis, SP-GC inhibits the hypernociception, edema and arthritic index in acute, sub-chronic and chronic phases. SP-GC did not alter the motor performance of animals. In conclusion, SP-GC exerts protective effect in models of arthritis due to the modulation of cell influx, IL-1ß and NO levels, culminating in the reduction of hypernociception and edema.

Administration of Wasabia koreana Ameliorates Irritable Bowel Syndrome-Like Symptoms in a Zymosan-Induced Mouse Model.

Irritable bowel syndrome (IBS) is a functional gastrointestinal disease with complex pathophysiology involving the brain-gut axis. To assess the effects of Wasabia koreana (WK) on IBS, we employed a mouse model of colonic zymosan injection presenting with diarrhea-predominant IBS-like symptoms. Oral WK administration significantly diminished stool score, suppressed colon length and weight change, and minimized body weight loss without affecting food intake. In WK-treated mice, the submucosal thickening and epithelial lining of the colon were inhibited and were similar to those of naïve mice. Infiltration of mast cells into the colon and serum tumor necrosis factor-α levels were markedly suppressed. These effects were comparable to those of sulfasalazine, an anti-inflammatory drug. Furthermore, the number of visceral pain-related behaviors was significantly decreased, and locomotion activities measured in the elevated plus maze and open field tests were significantly increased by WK in a dose-dependent manner compared with amitriptyline, an antidepressant. These changes were accompanied by reduced FosB2 expression in the brain. Taken together, these data suggest that WK may have potential as a medicinal food for IBS by acting on inflammatory diarrhea and neural activity.

Coenzyme Q10 suppresses Th17 cells and osteoclast differentiation and ameliorates experimental autoimmune arthritis mice.

Coenzyme Q10 (CoQ10) is a lipid-soluble antioxidant synthesized in human body. This enzyme promotes immune system function and can be used as a dietary supplement. Rheumatoid arthritis (RA) is an autoimmune disease leading to chronic joint inflammation. RA results in severe destruction of cartilage and disability. This study aimed to investigate the effect of CoQ10 on inflammation and Th17 cell proliferation on an experimental rheumatoid arthritis (RA) mice model. CoQ10 or cotton seed oil as control was orally administrated once a day for seven weeks to mice with zymosan-induced arthritis (ZIA). Histological analysis of the joints was conducted using immunohistochemistry. Germinal center (GC) B cells, Th17 cells and Treg cells of the spleen tissue were examined by confocal microscopy staining. mRNA expression was measured by real-time PCR and protein levels were estimated by enzyme-linked immunosorbent assay (ELISA). Flow cytometric analysis (FACS) was used to evaluate Th17 cells and Treg cells. CoQ10 mitigated the severity of ZIA and decreased serum immunoglobulin concentrations. CoQ10 also reduced RANKL-induced osteoclastogenesis, inflammatory mediators and oxidant factors. Th17/Treg axis was reciprocally controlled by CoQ10 treatment. Moreover, CoQ10 treatment on normal mouse and human cells cultured in Th17 conditions decreased the number of Th17 cells and enhanced the number of Treg cells. CoQ10 alleviates arthritis in mice with ZIA declining inflammation, Th17 cells and osteoclast differentiation. These findings suggest that CoQ10 can be a potential therapeutic substance for RA.

Antinociceptive and anti-inflammatory activities of crude methanolic extract of red alga Bryothamnion triquetrum.

The marine environment is an extraordinary reservoir of bioactive natural products, many of which exhibit chemical and structural features not found in terrestrial natural products. In this regard, the aim of this study was to investigate the possible antinociceptive and anti-inflammatory activities of a crude methanolic extract of the red alga Bryothamnion triquetrum (BT-MeOH) in murine models. Groups of Swiss mice of both sexes (25-30 g) were used throughout the experiments. The potential antinociceptive of BT-MeOH was evaluated by means of the following tests: acetic acid-induced writhing, hot-plate test and glutamate- and formalin-induced nociception. The anti-inflammatory activity of BT-MeOH was investigated using the zymosan A-induced peritonitis test. The tests were conducted using 100 mg/kg (p.o.) BT-MeOH, 33.3 mg/kg (p.o.) dipyrone, 35.7 mg/kg (p.o.) indomethacin and 5.7 mg/kg (s.c.) morphine. The extract and all standard drugs were administered 40 min before the nociceptive/inflammatory stimulus. In the acetic acid-induced writhing test, BT-MeOH and dipyrone inhibited the nociceptive response by 55.9% (22.2 ± 2.0 writhings; p < 0.01) and 80.9% (9.6 ± 2.1 writhings; p < 0.01). In the hot-plate test, BT-MeOH did not increase the latency time of the animals in the time evaluated. In addition, BT-MeOH inhibited glutamate-induced nociception by 50.1%. While BT-MeOH did not inhibit the neurogenic phase in formalin-induced nociception, the inflammatory phase was inhibited by 53.1% (66.8 ± 14.2 s; p < 0.01). Indomethacin inhibited the inflammatory phase by 60.2% (56.8 ± 8.7 s; p < 0.01). In the zymosan-induced peritonitis test, BT-MeOH inhibited 55.6% (6.6 ± 0.2 × 10(6) leukocytes/mL; p < 0.01) of leukocyte migration, while indomethacin inhibited 78.1% (3.2 ± 0.1 × 10(6) leukocytes/mL; p < 0.01). Based on the results obtained in this study, we conclude that BT-MeOH has peripheral antinociceptive and anti-inflammatory activities. However, more studies need to be conducted to confirm these properties.

Aqueous and Methanolic Extracts of Caulerpa mexicana Suppress Cell Migration and Ear Edema Induced by Inflammatory Agents.

The regulation of the inflammatory response is essential to maintaining homeostasis. Several studies have investigated new drugs that may contribute to avoiding or minimizing excessive inflammatory process. The aim of this study was to evaluate the effect of extracts of green algae Caulerpa mexicana on models inflammation. In mice, the inflammatory peritonitis model is induced by zymosan. Previous treatment of mice with aqueous and methanolic extracts of C. mexicana was able to suppress the cell migration to the peritoneal cavity, in a time-dependent but not in a dose-dependent manner. The treatment of mice with C. mexicana extracts also decreased the xylene-induced ear edema, exerting strong inhibitory leukocyte migration elicited by zymosan into the air pouch. We concluded that administration of the extracts resulted in a reduction of cell migration to different sites as well as a decrease in edema formation induced by chemical irritants. This study demonstrates for the first time the anti-inflammatory effect of aqueous and methanolic extracts from the green marine algae Caulerpa mexicana.

Intravital imaging of IL-1beta production in skin.

IL-1 is a prototypic inflammatory cytokine that has pathogenic roles in various skin disorders. Although Langerhans cells (LCs) have been reported to express IL-1beta mRNA upon application of contact sensitizers, it remains unclear whether other cell types produce IL-1beta in skin. Thus, we sought to directly identify IL-1beta-producing cells in living animals by construction of transgenic mice expressing DsRed fluorescence protein gene under the control of IL-1beta promoter. Little DsRed fluorescence signal was detected in skin under steady-state conditions. Striking increases in DsRed signal were observed after topical application of a contact sensitizer, oxazolone, which also induced markedly elevated IL-1beta mRNA and protein expression. DsRed signal was expressed primarily by CD45(+)/CD11b(+) myeloid leukocytes in both epidermal and dermal compartments and was detected only in small fractions of epidermal LCs. Interestingly, DsRed(+) cells emerged preferentially as clusters around hair follicles. Intravital confocal imaging experiments revealed highly motile potentials of DsRed(+) cells-they constantly crawled around hair follicles via amoeba-like movements with a mean velocity of 1.0+/-0.4 microm min(-1) (epidermis) or 2.7+/-1.4 microm min(-1) (dermis). The newly developed in vivo imaging system represents a useful tool for studying spatial regulation of IL-1beta production in skin.

Characterization and pharmacological evaluation of febrile response on zymosan-induced arthritis in rats.

The present study investigated the febrile response in zymosan-induced arthritis, as well as the increase in PGE(2) concentration in the cerebrospinal fluid (CSF), along with the effects of antipyretic drugs on these responses in rats. Zymosan intra-articularly injected at the dose of 0.5 mg did not affect the body core temperature (Tc) compared with saline (control), whereas at doses of 1 and 2 mg, zymosan promoted a flattened increase in Tc and declined thereafter. The dose of 4 mg of zymosan was selected for further experiments because it elicited a marked and long-lasting Tc elevation starting at 3 1/2 h, peaking at 5 1/2 h, and remaining until 10 h. This temperature increase was preceded by a decrease in the tail skin temperature, as well as hyperalgesia and edema in the knee joint. No febrile response was observed in the following days. In addition, zymosan-induced fever was not modified by the sciatic nerve excision. Zymosan increased PGE(2) concentration in the CSF but not in the plasma. Oral pretreatment with ibuprofen (5-20 mg/kg), celecoxib (1-10 mg/kg), dipyrone (60-240 mg/kg), and paracetamol (100-200 mg/kg) or subcutaneous injection of dexamethasone (0.25-1.0 mg/kg) dose-dependently reduced or prevented the fever during the zymosan-induced arthritis. Celecoxib (5 mg/kg), paracetamol (150 mg/kg), and dipyrone (120 mg/kg) decreased CSF PGE(2) concentration and fever during zymosan-induced arthritis, suggesting the involvement of PGE(2) in this response.

The effect of zymosan and the protective effect of various antioxidants on fracture healing in rats.

AIM: To investigate the effects of free oxygen radicals and various antioxidants on bone healing after experimental formation of fracture. MATERIALS AND METHODS: Fifty male rats were used and divided into five groups (ten rats in each). The right forelimbs of the rats were broken by bimanual compression method. One hour before this procedure, 5 ml/kg of intraperitoneal (i.p.) physiologic saline were given to the control Group 1. All 40 rats in the experimental Groups 2, 3, 4 and 5 were treated with i.p. zymosan at a dosage of 100 mg/kg to induce the production of free radicals by stimulating NADPH oxidase in polymorphonuclear leukocytes. Zymosan induction was stopped on the fifth post-fracture day. In addition to the zymosan, i.p. 1 g/kg/day of dimethyl sulfoxide were given to the animals in Group 3, 50 mg/kg/d of Ginko biloba Extract (EGb 761) in Group 4 and 500 mg/kg/day of vitamin C in Group 5. Radiographs of the fractures of all animals were obtained to assess callus formation, remodeling and bridging bone formation under ether anesthetics on postfracture day 7, 14 and 21. All rats were euthanized on day 22, and sections of the radius and ulna were examined both histologically with light and electron microscopy and ultrastructurally. Statistical analysis was made with Kruskal-Wallis variance analyze test and comparison between groups was performed by Dunn's multiple comparison test. RESULTS: An impairment of bone healing was observed in Group 2 inducted with purely zymosan. Variable results were obtained for bone healing in the groups treated with various antioxidants. There was very significant difference of fracture healing between Groups 1 and 2 both histologically and radiologically (P < 0.001). There was significant difference between Groups 2 and 5 radiologically (P < 0.05). CONCLUSION: Free oxygen radicals demonstrate a negative effect on fracture healing and vitamin C (an antioxidant) partially prevents the negative effect of zymosan on fracture healing.

Low-level laser therapy for zymosan-induced arthritis in rats: Importance of illumination time.

BACKGROUND: It has been proposed for many years that low-level laser (or light) therapy (LLLT) can ameliorate the pain, swelling, and inflammation associated with various forms of arthritis. Light is thought to be absorbed by mitochondrial chromophores leading to an increase in adenosine triphosphate (ATP), reactive oxygen species and/or cyclic AMP production and consequent gene transcription via activation of transcription factors. However, despite many reports about the positive effects of LLLT in arthritis and in medicine in general, its use remains controversial. For all indications (including arthritis) the optimum optical parameters have been difficult to establish and so far are unknown. METHODS: We tested LLLT on rats that had zymosan injected into their knee joints to induce inflammatory arthritis. We compared illumination regimens consisting of a high and low fluence (3 and 30 J/cm(2)), delivered at high and low irradiance (5 and 50 mW/cm(2)) using 810-nm laser light daily for 5 days, with the positive control of conventional corticosteroid (dexamethasone) therapy. RESULTS: Illumination with 810-nm laser was highly effective (almost as good as dexamethasone) at reducing swelling and a longer illumination time (10 or 100 minutes compared to 1 minute) was more important in determining effectiveness than either the total fluence delivered or the irradiance. LLLT induced reduction of joint swelling correlated with reduction in the inflammatory marker serum prostaglandin E2 (PGE2). CONCLUSION: LLLT with 810-nm laser is highly effective in treating inflammatory arthritis in this model. Longer illumination times were more effective than short times regardless of total fluence or irradiance. These data will be of value in designing clinical trials of LLLT for various arthritides.

Low-frequency electroacupuncture suppresses zymosan-induced peripheral inflammation via activation of sympathetic post-ganglionic neurons.

Electroacupuncture (EA) is used to treat a variety of inflammatory diseases; however, the neurophysiological mechanisms underlying EA's anti-inflammatory effect remain unclear. Accumulating evidence suggests that the sympathetic nervous system regulates immunologic and inflammatory responses and thus we hypothesized that this system could be involved in EA's anti-inflammatory effect (EA-AI). The goal of the present study was to evaluate whether the sympathetic nervous system plays a critical role in EA-AI using a mouse air pouch inflammation model. We found that bilateral low-frequency (1 Hz) EA applied to the Zusanli acupoint significantly suppressed the number of zymosan-induced leukocytes migrating into the air pouch. Furthermore, double-labeling immunohistochemical experiments showed that EA stimulation increased Fos expression in choline acetyltransferase (ChAT)-positive sympathetic pre-ganglionic neurons in the intermediolateral region of thoracic spinal cord segments. Chemical sympathetic denervation by intraperitoneal injection of 6-hydroxydopamine (which spares sympathetic adrenal medullary innervation) significantly inhibited EA-AI. In contrast, adrenalectomy did not alter EA-AI. Finally, systemic propranolol administration significantly inhibited EA's anti-inflammatory effect, suggesting that beta-adrenoceptors are involved. Collectively, these results suggest that EA produces an anti-inflammatory effect in this mouse air pouch model by activating the sympathetic nervous system leading to the release of catecholamines from post-ganglionic nerve terminals, which act on beta-adrenoceptors on immune cells to inhibit their migration.

Reactive nitrogen species scavenging, rather than nitric oxide inhibition, protects from articular cartilage damage in rat zymosan-induced arthritis.

1. The contribution of nitric oxide (NO) and peroxynitrite (PN) to inflammation in a zymosan-induced (1 mg, intra-articular, i.art.) rat model of arthritis was assessed by histopathology and by measuring the glycosaminoglycan (GAG) content of the articular cartilage. 2. Progression of the chronic synovitis in zymosan-induced arthritis (ZYA) was associated with increased nitrite and nitrotyrosine (3-NT) levels in the joint exudates that paralleled a progressive loss of the GAG content. An increase in 3-NT was also observed after i.art. PN. 3. The nonselective nitric oxide synthase (NOS) inhibitor l-N(G)-nitroarginine methyl ester (25-75 mg x kg(-1)day(-1)) or the selective inducible NOS inhibitor aminoguanidine (50-100 mg x kg(-1)day(-1)) given 1 h before (prophylactic) or 3 days after (therapeutic) injection of the zymosan ameliorated the synovitis, but worsened the GAG loss, as measured at the end of the experiment (day 7). 4. The PN scavenger uric acid (100-250 mg x kg(-1) i.p. four times daily) given prophylactically until the end of the experiment (day 14), in a dose compatible with its PN scavenging activity, significantly decreased both the synovitis and the GAG loss. 5. In conclusion, PN formation is associated with cartilage damage in addition to proinflammatory activity in ZYA. NOS inhibitors and a PN scavenger were able to reduce the cellular infiltration, while displaying opposite effects on cartilage homeostasis either by enhancing or ameliorating the damage, respectively.

The preclinical pharmacological profile of the potent and selective leukotriene B4 antagonist CP-195543.

CP-195543 [(+)-2-(3-benzyl-4-hydroxy-chroman-7-yl)-4-trifluoromethyl-benzoic acid] is a structurally novel, selective and potent leukotriene B4 (LTB4) receptor antagonist. In vitro CP-195543 inhibited [3H]LTB4 binding to high-affinity LTB4 receptors on human neutrophils (HN) and murine spleen membranes with IC50 values of 6.8 nM (Ki = 4.9 nM) and 37.0 nM (Ki = 26.9 nM), respectively. CP-195543 inhibited human and mouse neutrophil chemotaxis mediated by LTB4 with IC50 values of 2.4 nM and 7.5 nM, respectively. Evidence of noncompetitive antagonist effects on the HN high-affinity LTB4 receptor was obtained by Scatchard analysis of [3H]LTB4 binding to and chemotaxis of HN to LTB4. Scatchard analyses of [3H]LTB4 binding to low-affinity receptors on HN indicated that CP-195543 acted as a competitive antagonist at this receptor, and inhibition of LTB4-mediated CD11b up-regulation on HN was inhibited competitively by CP-195543 (pA2 = 7.66). In whole blood, CP-195543 also blocked CD11b up-regulation on HN (pA2 = 7.12) and murine neutrophils (pA2 = 7.06) with a similar potency. LTB4-mediated CD11b up-regulation on human monocytes and eosinophils in whole blood were inhibited by CP-195543 with IC50 values of 270 nM and 420 nM, respectively. CP-195543 at 10 microM failed to inhibit HN chemotaxis and CD11b up-regulation mediated through alternative (i.e., complement fragment 5a, interleukin-8, platelet-activating factor) G-protein-coupled chemotactic factor receptors. In vivo, after oral administration, CP-195543 blocked LTB4-mediated neutrophil infiltration in guinea pig and murine skin with ED50 values of 0.1 mg/kg and 2.8 mg/kg p.o., respectively. When administered in osmotic pumps, CP-195543 reduced the clinical symptoms and attendant weight loss in an IL-1-exacerbated murine model of collagen-induced arthritis with half-maximal effects associated with plasma drug levels of 0.4 to 0.5 microg/ml. Collectively these data provide evidence of the in vitro potency and in vivo efficacy of a novel LTB4 antagonist and support its clinical evaluation in a variety of inflammatory diseases in man.

Protective effect of anisodamine on cultured bovine pulmonary endothelial cell injury induced by oxygen-free radicals.

Anisodamine, a Chinese traditional medicine herb, has been used for treatment of adult respiratory distress syndrome effectively, but little is known about its mechanism. We attempted to investigate if anisodamine could protect bovine pulmonary endothelial cell injury induced by exogenous oxygen-free radicals that were generated by xanthine/xanthine oxidase or opsonized zymosan-stimulated polymorphonuclear leukocytes. Results showed that with the addition of xanthine/xanthine oxidase into cultured bovine pulmonary endothelial cells, production of malondialdehyde and release of lactate dehydrogenase in supernatant increased, and synthesis of prostacyclin decreased. Damaged cellular membranes were revealed by scanning electron microscopy. The same was true for the addition of opsonized zymosan-stimulated polymorphonuclear leukocytes. While treatment with anisodamine greatly attenuated all of the above-mentioned parameters, results showed that (1) cultured bovine pulmonary endothelial cells could be damaged by oxygen-free radicals, (2) anisodamine had a protective effect on this injury as effective as that of superoxide dismutase and catalase, and (3) the membrane-stable action might contribute to the mechanism of protective effect against this injury.